How to sew a ripping zipper back on Is there a good technique for repairing a zipper that is ripping apart from the lining? About 4 inches have torn away from the fabric and I really don't want to replace the whole zipper because it will disrupt the appearance of the coat. I'm wondering if I should just stitch the still-attached part more solidly to the fabric to prevent further ripping, or if I can get enough of the remaining fabric on the zipper re-attached to the fabric.

(apologies for any lack of etiquette here, first time posting in Arts & Crafts!)

It looks like the zipper tape has frayed, so there's not much left to stitch to. I think the best course of action would be three steps:

Stabilize the fraying zipper tape
Reinforce the fraying zipper tape
Re-stitch the coat fabric to the zipper tape

There are a few ways to tackle #1. I'd probably douse the frayed zipper tape in a significant amount of Fray Check, especially right around the area near the teeth just where the fraying starts. Then, dig out your mini iron, take some fusible web (Heat n Bond) and iron it to some woven fabric to make some stabilizer, or get some medium-to-heavy iron-on interfacing, and iron it to the fraying parts (and about-to-be-fraying parts) of the zipper tape, to reinforce them with extra strength before you try to re-stitch the zipper to the coat.

I'm afraid that if you try to stitch it as it is now, there's not enough zipper tape to hold your stitching, and it'll pull right out again.

Good luck!


How to cut a tiny circle in paper? When papercutting, one often has to cut very small circles, like below. When I do that, I often break my blade. How should I cut small circles or other small holes? Think about ...

Should I apply pressure or not?
Should I only turn the knife on its place or really move it?
Should I hold the knife vertically or diagonally on the paper?

Punch it

Given the size of the holes you are doing this might not seem like useful advice but I would bet that this is what the artist in the picture did, as those are not perfect circles. Outside of this you could use a small punch to get a perfect circle.

The way you get that to work is put a lot of paper (or some other thick material) underneath so that the "work" paper will be less likely to tear out.

For larger holes or if punches are not available

Whatever you need to do that feels comfortable so that you can do one continuous cut. As with all cutting make sure you are using tools that are sharp!

  Should I only turn the knife on its place or really move it?

Keeping the work stationary for me is a problem especially for circles, as you are moving your wrist and arm around more, which could put strain (cramping from repetition) on you faster (which in turn is asking for small mistakes). This can also reduce your control of the cut. I am in favour of moving both the work and your hand at the same time. I find this makes the motions easier and they take less time.

  Should I hold the knife vertically or diagonally on the paper?

While the cut would naturally be at a slight angle with what I am describing, I would try to avoid doing so and try to cut as vertically as possible. Cutting on a diagonal can weaken the edges of the cuts making more susceptible to damage.

It is definitely important to try and do the cut in one pass. Hesitation or multiple cuts can create nibs or stray fibers. This is fixable of course but you have to remove more material which can affect the shape. However if done right corrections like that can be hidden as most people won't notice.

  Should I apply pressure or not?

Not sure of the best answer to this other than not too much. You want the knife to do the work. As long as your tool is sharp you should not have to put too much force into it.


Book binding with hot glue I watched a couple of videos on YouTube regarding book binding with hot glue: in short, they were presenting that the pages should be put together in a press and then hot glue is applied on the side.
However, I am not confident in this method, because I don't think that simply applying hot glue on the side will keep all the paper sheets in their place.
I haven't tried this method before, but I am looking for suggestions (in case I missed something).
What is the best method to bind books using hot glue?

This appears to be one of the methods used to manufacture paperback books.
However the pages in a paperback have a rough back edge, not a clean cut, this allows more surface for the glue to bond to.
Some binding machines also use hot glue.


confused about varieties of linseed oil I am fairly new to oil painting. Please explain the differences between refined linseed, cold-pressed linseed, boiled linseed, double-boiled linseed, etc. I am confused with the variety and would like to know the drying times and how these affect the quality of the painting?

I am not a painter in any sense of the word. Using a search engine, I found this site. While not being exhaustive, it explains some of the information interesting to you.

REFINED LINSEED OIL

This is the most popular form of oil medium. It slows down the drying time of the paint, and when painting in layers, this can be very useful. Apply the ‘slow over fast rule’ – paint your fast-drying layers first, and then each layer on top should take longer to dry than the previous one. You can therefore apply more of this medium with each layer.

The [brand name] Refined Linseed Oil increases gloss and transparency as well as smoothing the consistency of oil paint.

There is also a Cold Press Linseed Oil by [brand name], which is a high quality oil often used when grinding pigments, to create oil paint at a professional level. It dries more slowly than Refined Linseed Oil, taking up for four days, and has a shinier and harder finish.

Other information can be found using search engines. If you want to actually improve your painting skills, you might want to attend some classes led by a professional.


Sewing a double-sided nylon garden flag I am using nylon to make a garden flag and read that there should be a liner between the 2 layers so the design does not show through to the other side.  Any suggestions for the fabric to use for this liner?  It should dry quickly when it rains but block the sunlight from showing the design to the opposite side of the flag.

Also, how hot an iron can be used to apply a heat bond applique product to the nylon for drawing the designs then cutting them out?

Q1: I'd suggest sewing a layer of black nylon between. Black will block any light trying to shine through the flag, and only allow light to be on the flag.

Q2: Does the nylon need to be bonded before cutting? If the nylon is being heat-bonded to the flag (I'm assuming this is the same project), I would do a test run with some scraps:

wood board
aluminum foil
fabric (face-side down)
bonding material (interfacing?)
a layer of wax paper and/or another of aluminum foil
top it off with a wet rag

and iron that fabric sandwich.

The wood will keep everything still and help prevent slips or stretches
The wood and foil should help keep the heat localized
The layer above the adhesive should be something easily removable, like pulling a sticker off it's original waxy paper
If using another layer of foil, it'll again just help direct that heat to whatever is under the foil
The wet cloth is important, and perhaps keep some extra water handy -- heated water will not go above 212F, so as long as the cloth is wet, that's going to be the highest temperature you should be able to use. Most interfacing should melt at this temperature.

If you're bonding nylon to nylon, just make sure that wherever you have exposed heat-bonding stuff you keep it covered with wax paper or something like that.

Oh, and if you're avoiding sewing altogether, just use the same heat-bonding stuff around the edges of the inside part of the overall flag. You could take the black nylon, cut it to the same shape as the other two faces of the flag, then heat-bond one face to the liner at the edges, then do a second round of heat-bonding (I'd suggest two separate ironings for this, you wouldn't want one face to only partially bond because it didn't get enough heat for the glue to melt)

HTH


Does washi tape stick on skin? I'm looking into putting together a Neil "Crazy" Craver costume. He is an athlete on American Ninja Warrior. He wears a lot of gold and decorates his chest and arms with gold stickers/temporary tattoos. Would washi tape stick to skin well enough to help me complete this look? I've never used washi tape, but I'm finding a bunch of great gold washi tape options online. Looking for opinions before I buy.

Image of Neil "Crazy" Craver for reference: https://www.alamy.com/stock-photo-los-angeles-ca-usa-24th-aug-2016-neil-craver-at-arrivals-for-american-115890179.html

This is washi tape. I often keep some on hand.

Ha ha, let’s test it on my hand.

It stays on for a while, but doesn’t bend like adhesive bandages. So, once the edge pops up, it is compromised. Sweat or moisture will not keep it on. Removing it once compromises it as well. It might stick for a while depending on movement.


What causes frosting when applying a varnish? Sometimes when applying the final varnish on a miniature, it ends up going opaque / frosting.  What causes this to happen, and how can it be prevented?  I have seen this occur with both Vallejo and Liquitex gloss varnish, while using a brush to apply.

What system are you using? Airbrush or bottle spray?

I have experienced a lot of frosting when applying varnish in humid environments.
I have observed more frosting with spray bottles compared to airbrush (I dilute the varnish for airbrushing with Vallejo airbrush thinner).
Only apply a very thin layer of varnish at a time. I have observed frosting when I put too much varnish at once, especially with spray bottles. If more is needed, several thin layers may be applied.


How to cast silicone beads? I want to make custom, food-grade silicone beads that have a hole down the center for stringing them.

When I google molding silicone or any variation on that, all the results are to make silicone molds! Not for making silicone products or jewelry.

Does anyone know of any tutorials out there they can point me too?

If your objective is to create a silicone product, take a different viewpoint of your research thus far. Silicone molds work because silicone sticks to almost nothing other than silicone. If you create a mold using silicone as the foundation, pouring food materials inside means you get food materials out, without sticking.

For your beads, consider that you want a non-silicone mold. The hole in the center makes things a bit trickier, but not by much. You'd have to make a two-part mold and ensure that you get proper venting when placing the sprue for filling. Alternatively, if you don't mind a seam in the finished product, you can make two molds that can be filled independently.

You didn't state the diameter of the beads, and I'll adjust this suggestion to focus on small sized beads, as the project gets easier with increased size.

One will presume that you have ordinary beads of the size you wish to duplicate. The typical method of creating a non-silicone mold requires that the item be coated with a mold-release substance. Tiny beads are likely to be very challenging in that respect and you cannot expect one hundred percent perfection, in my opinion.

A somewhat step-by-step method would be as follows:

Create a modeling clay base, leveled as carefully as possible.
Embed the beads in the base to the half-way point, ensuring that the orientation of the through-hole is vertical.
Embed also in the base at various locations across the bed alignment points. These points can be clay-formed bumps, pyramids, cones, something tapered for easy release. Tapered depressions will also serve well.
Coat the beads and the clay surface with mold-release.
Encase the clay bed within an appropriate box-like structure to create a pouring frame.
Select a desired resin and fill to cover the beads and alignment points.
When cured, remove the clay bed but leave in place or clean and replace the beads.
Clean and apply mold release to the cured mold and the beads.
Create a new pouring frame around the cured mold.
Pour the second half of the mold, allow to cure as before.

When the mold are split and cleaned, any silicone compound applied will form the beads. Without cutting a sprue or vent, you can fill one mold flush with silicone, allow it to cure. Do not touch the cured surface. Fill the other half of the mold with silicone and place the first half in place atop it.

The uncured silicone will bond with the previous pour and create the beads. Depending on the amount of silicone used, there may be thicker seams.

I do not believe small beads can be created using molds involving a sprue and vent. Because the spherical shape of a bead requires a two part mold to release the bead, it is more practical to consider the seam-style creation.

The tricky part will involve ensuring the clay bed fills the bead opening when pressing them in place in the earlier steps. Cleaning the clay from those openings when creating the second mold is equally important. Any points of failure in those items will create a bead without a pass-through hole.


Materials for flame proof signage I want to make attractive signs to point to the locations of fire shelters for our community, in a fire-prone area.  I want something that would be visible to rescuers after going through a bush-fire of 1000 degree celsius or so.

The simplest approach would be to cut the signs out of sheet metal.  But I'm wondering if anyone has ideas for materials that might retain color?

Since fire coats the things it can't destroy in black opaque soot, it doesn't really matter if the colors underneath survive... they won't be seen until after someone cleans the sign, after the fire is over.

I would suggest using the sign's shape to convey its meaning.  That way, even when it is totally blackened and silhouetted against a wall of flames behind it, its meaning will still be clear.

As for material suggestions, I would consider aircrete ( a mixture of concrete with a foaming resin ) which is extremely fireproof.  Also, there are a lot of additives that you can add to concrete (and by extension aircrete). Gypsum or Quartz powders will make the sign reflect flashlight beams. Dyes and colored stones can be added to increase the sign's unsooted visibility and some to those dyes absorb sunlight and glow in the dark.  The sign can either be made relatively attractive or garishly noticeable with very little additional effort.


How to measure the distance to horizon line one-point perspective? I am drawing a room, which is 10m x 10m (or whatever units).

I am drawing it in one point perspective.

How do I determine exactly where to draw the back wall? As in, how far back.

This solution will work any shape of room you have. Cubic, rectangular (as I demonstrate), and even rooms you aren't looking at from straight on (in which case you rotate the top elevation, a common perspective technique).

Click on any image for a larger view.

Layout the general lines.

a) You need three horizontal lines: your horizon line, a ground line (somewhere below the horizon), and a vantage line. In this example, my vantage line is below the ground line. The vantage line represents the distance of the viewer from the horizon.
b) You also need to choose a vanishing point somewhere on the horizon line.
c) You can pick a vantage point, but in this case its only purpose is to establish where to put vantage line
d) Draw the front elevation of your room, with the scale dimensions. The front elevation needs to rest its bottom-most line (or point, if rotated for 2-point perspective) on the Ground Line
e) Draw the top elevation of your room, with the scale dimensions. The top elevation needs to be under the Vantage Line, with its top-most line (or point, if rotated for 2-point perspective) on the Vantage Line.
f) Draw the front view of your room, aligned with both the front and top elevations

The real trick to this technique is mapping the angles between corners to the Measuring Points on the Horizon Line.

a) From a bottom corner of your top elevation, draw a line going through the opposite corner (such as bottom-left to top-right) and continue that line all the way to the Horizon Line
b) Where those lines intersect, mark that point as a Measuring Point
c) Repeat for the other bottom corner

Draw your normal perspective lines on your room

a) Don't worry about the back wall quite yet, just make sure your perspective lines go either all the way to the vanishing point, or far enough that you can be reasonably sure you have room for your back wall

Now the technique comes into play. You'll use the Measuring Points to map a projection to tell you where the back wall begins

a) From a bottom corner of your perspective room, draw a line to the matching Measuring Point. So, if you pick the bottom-right corner, draw a line towards the Measuring Point that connects to the bottom-right corner of your top elevation.
b) Where this new line intersects your normal floor perspective lines represents the corner of your back wall.
c) You don't need to map the other bottom corner, unless you're drawing a room/shape that doesn't have parallel front and back walls
d) Draw a horizontal line from the back corner you measured to the other side of the floor

Standard perspective techniques will give you the top of the back wall.

a) Draw vertical lines from the bottom corners, and the points where they intercept are your ceiling's back corners

Go over your final guidelines and clean it up!

a) You're done!


Casting foam inlay for briefcases I would like to create a foam holder for my stuff to be placed in a briefcase kind of like this

The shaped of the object is fairly complex with lots of curves, and simply cutting a straight through hole is not a snug fit. Since i have access to
vacuum forming machine, i can easily create a negative of my object. But i am having a hard time finding guides for casting foam

Casting foam inlays isn't all that different from creating a silicone mold, except the mold is mostly pressure-sealed; the foam creates a lot of pressure, so the mold needs to be strong enough to handle it.

The foam is related to Gorilla Glue, so it takes meticulous prep and plenty of mold release everywhere if you want to be able to take the mold apart and remove your insert.  It has short working time, so everything must be ready to go once you start, and you don't have much time for cleanup.  If you've never done a large, complex casting, this would not be a good starting project.

Creating the foam inlay is similar to making a mold of what will be the cavities.  If you want complex cavities, you'll need to make complex forms.

Vacuum-forming a positive cavity shell will create an oversized (loose-fitting) form, unless you vacuum-form an undersized pattern.  Vacuum-forming the actual items may work if the cavities are deep enough, especially if you cover everything with a foam top sheet inside the briefcase.  The foam builds enough pressure to potentially break the mold shell, so a positive vacuum-formed cavity mold will need to be backfilled with something solid, like plaster, to avoid it being crushed.

Alternately, you could use the vacuum-formed shell as a negative to cast a solid replica of the items, then use the replica for the cavities in the inlay.

Here's a good tutorial video showing details of a similar project (making a foam inlay for a drawer for camera equipment): https://www.youtube.com/watch?v=OYP-l4VwKF0.

This kind of application is typically done with foam sheets, though.  It's a lot cleaner and easier.  Rather than starting with a thick sheet of foam, it's usually done with layers.  Here's a video of a guy making a tool drawer insert from foam sheets from a craft store: https://www.youtube.com/watch?v=rbKtUvpUCyc.  In this case, he did it with a cutout in a single layer of the desired depth.

There's a product called Kaisen Foam that's designed for this application.  It's a number of layers of polyethylene foam tacked together.  You cut out the outline and peel away the waste one layer at a time.  For irregular parts, the next layer can be removed only where additional depth is needed.  It's stiff enough that you can cut it on a bevel.  Here are a couple of videos for similar projects: https://www.youtube.com/watch?v=dwe0QEvG1ew, and https://www.youtube.com/watch?v=G4sjbtSw5m8


How do I replace a rotten wood base to a plaster statue? I have a religious statue that I would like to repair.

Unfortunately, it has been stored in a VERY damp basement, and its wooden base, underneath the plaster, is rotten, causing the plaster feet of the figure to crumble badly. The wood needs to be replaced, which means I will have to remove the crumbled feet and bottom of dress, and make new ones. I think I can do the sculpting and replastering, but the wood is beyond my experience.

Does anyone have experience with this kind of restoration?

The statue is approx. 49 inches (125 cm) high, and base is approx. 15" (38 cm) wide x 10" (25 cm) deep. She weighs about 20 lbs (9 kg) (est.).

Looks like the original plaster covered the wooden base, which makes for excellent repair possibilities. Though removing the existing base may prove tricky.

As a result you may not want to remove it at all. As Fixer1234 points out you may run into some additional problems if any of the armature is under tension from how it was attached to the wood, something we won't know until it either has or hasn't caused additional damage on removal of the base. As a result you could leave the base in place, and apply a wood hardener, which come in many brands but are resins and epoxies designed for filling in the damaged parts of wood making it firm again. Since the wood itself is not part of the visible statue, you could save a lot of trouble simply by leaving it in place and letting the plaster restoration cover it.

In the situation that the wood is really crumbling away, as in you can peel it off with your fingers, the wood hardener won't work very well. Though at that point removing it should be pretty easy.

In all of the below possibilities, use hand tools. The vibration of a power drill or other tool might help shake the base loose, but it is more likely to do damage to the statue. Additionally you may want to trace the outline of the original base before pulling it off, in case it is destroyed in removing it.

After she is completely dry. I would lay her on something soft and look underneath the wooden base to see if there is any obvious attachment to the rest of the statue, you may find that an armature has been bolted to the wooden base and goes through the plaster statue to help support it from falling under its own weight.

If you can find a bolt remove it. Then give the base a bit of a jiggle see if it just comes loose. Not much, just enough to shake loose any plaster touching the wood. It is quite possible that even if there is a bolt, it is not the only thing holding the armature to the base. So...

If you don't see anything bolted, or the jiggle didn't pop off the base. The armature likely is many smaller, still heavy, wires that fit into holes drilled into the wooden base, and probably glued into place. For 20 pounds at 49 inches I would guess that she is hallow. Which is useful as you can probably get an idea of where the armature is attached to the base if you can see inside. Looks like the damage between her feet might offer a place to look. If you can identify any attachments to the base you may have some luck pulling the wood out from behind them. If it is really rotten wood it will come away quickly, and even mostly ok wood can be removed with careful scraping from some wood carving tools, such as a gouge or a small chisel.

If you're not finding how the base is attached you might want to trim off bits of it in layers. If the wood is significantly rotten, it will fall away by itself. Otherwise either without a hammer, or with the lightest tap of a hammer put the chisel at parallel with the grain of the wood near the bottom and twist it a little bit to pull a chip off. It would be slow, but you could potentially pull the whole base off in chips. I would only really do this if the wood is rotten to the point that it is easy to do, if it is still pretty hard, I would get impatient and rely too much on the hammer.

Once you have the base off, a new one will be fairly straight forward. Take your tracing, or the original base, and place it on a new piece of wood of the right thickness. Trace out the oval shape. You can cut it out with a hand saw, just cut out corners until it sufficiently resembles an oval. If you're comfortable working with them, a table saw or jigsaw would work as well.

If there were holes drilled in the original for the armature to fit in, put some chalk on the bottom of each armature wire and bump the fresh base into them so there is a chalk mark for where to drill the holes. If there was a larger rod bolted through the base, drill the hole for this first (can use the chalk method here too) then go back for the smaller wires if they are also present such that the base can now reach them without getting caught on the main support.

The best part about it, is if the cut for the new base isn't perfect, it will be covered by plaster when you're done, so no one will see it. As such you shouldn't need to make a jig or similar to cut it out, by eye should be fine.


How do I cut the bottom off a glass wine bottle? Recently at a party, I saw empty wine bottles that had the base cut off so it could be placed over a candle. It made an elegant and interesting centerpiece, and I have some very pretty wine bottles that I'd love to convert to candle covers.

How do I cleanly and safely cut the base off a glass bottle? I'd like a reliable method so I don't risk destroying the bottles (I don't have many of them).

There are a few different ways to do this, but most of them involve extremes of temperature: first intense heat along the line where you want to cut the bottle, and then submerging in cold water, repeated several times if necessary.

A Song of Water and Fire

This method assumes you have a tool with which to score the glass, for instance a glass drill bit or glass cutter, both of which should be reasonably inexpensive to get hold of. First use this to mark the line along which you want to cut the bottle. Then apply heat to this line; you can do this in a couple of different ways:

by rotating the bottle slowly over an open flame, making sure the flame is directly under the score line so that it doesn't heat too broad an area of the bottle
by pouring a thin stream of boiling water onto the score line from above, again trying not to let it cover too wide an area

After heating the bottle up along the score line, dunk it in a pail of cold water (which you should have prepared beforehand). The shock of passing from heat to cold should weaken the bottle and make it likely to crack along the existing score line.

It's likely that the bottle won't break the first time you do this, but keep repeating the process multiple times (heat, cold water, heat, cold water) and eventually the bottle should snap in the right place.
String and nail polish remover

Again the basic idea is to alternate extreme heat with extreme cold, but this time you don't need to have a scoring tool because you'll be using a piece of string. You also need something containing acetone, the most commonly used example being nail polish remover.

Take a piece of string, soak it in nail polish remover (or anything else acetoney), and wrap it around the place where you want to cut the bottle. Then set the string on fire, which will apply intense heat to the narrow area on the bottle around where the string is tied. (Obviously, you need to take care that the string doesn't slip to a different position on the bottle. Even more obviosuly, make sure you don't have any of the acetone on your fingers and that the bottle of nail polish remover is placed well away from the flame.) When the flame burns out or you feel enough heat has been applied, dunk the bottle in a pail of cold water as before to provide the stress necessary to crack it.

Again, this is unlikely to work the first time, but you can keep repeating the process, either re-soaking the string to light it again or replacing it by a new piece of string if necessary.

Whichever method you use, the bottle may not snap completely cleanly, so you should use some sandpaper to smooth off the edge of the broken bottle before using it.

You can see pictures and videos of the process here and here. I'll try to add some images and hopefully gifs to this answer later on.

There's also an urban myth that you can cut glass underwater with just an ordinary pair of scissors. I'm not sure whether or not this is true, and I haven't gone to research it, simply because it wouldn't be relevant for your problem anyway. A rigid object in the shape of a hollow cylinder can't be cut with a pair of scissors whatever material it's made of; the underwater cutting, it true, would only work for flat panes of glass.


Advice on sewing bandages? I am working on a costume for an upcoming convention and the character that I am recreating has bandages that wrap all the way from his hands up to his shoulder (see image below):

I would prefer not to just wrap bandages all the way up my arm every time I wanted to use the costume and so was wondering if anyone had any experience or advice on sewing bandages, as I've found that they don't sew or hold together very well.

In essence I'm just looking to know what the best way of creating a reusable bandage sleeve would be.

A couple options appear for your objective. Substitute sewing with fabric glue and apply sparsely. Most bandages of the sort you have pictured are elastic and would not take well to sewing, as you've noted. By the same token, they would also not take well to heavy adhesive application.

One would apply dots of adhesive spaced along the edges where overlapped, allowing the stretchy part to stretch, while keeping the glued portions small and spaced closely enough to avoid gaps but not so close as to eat up the stretch required for a good fit.

One would desire to keep the stretch forces to a minimum while applying the bandages on a suitable model arm and secure the bandages as needed with tape or similar products while the glue cures.

Testing would be desirable to determine how much stretch the glue can handle before failing, then adjust spacing accordingly.

Another option would be to use a carrier sleeve and glove, perhaps slightly oversized if such a factor is not a problem. The sleeve would reduce or prevent the stretching while either stitching or adhesive would secure the bandages in the desired locations. A suitable model would accelerate the process, as noted above. I don't believe it would be a simple matter to machine stitch on a sleeve and hand-stitching would require patience and determination.


Are there cases where we do not reverse stitch when sewing? I purchased a Singer Start 1304 Sewing Machine and am watching tutorials.

In one of them, the lady demonstrates how to make a simple stitch. She goes a few stitches forward, a few stitches back, and continues stitching forward to the end.

Then she goes a few stitches back, a few stitches forwards, and then cuts the fabric:

https://youtu.be/ZC0Rhc_stfI?t=799

Later in the video, she demonstrates making a zig-zag stitch. However, she does not demonstrate going back a few stitches in the beginning, and going back few stitches in end:

https://youtu.be/ZC0Rhc_stfI?t=900

Is this correct?
If I decide to make a zig-zag stitch, should I only go forwards (and not backwards)?
If so, then how do I ensure my zig-zag stitch does not come apart?

To understand when to use backstitching, you need to understand the purpose of it in the first place. It's not just "a thing that is done," it is a technique to "lock" the stitches in place on a seam. To illustrate this for yourself, get some scrap fabric and stitch two pieces of it together along a straight edge. Backstitch at one end, and just stitch off the edge on the other, trim the threads, then attempt to pull the fabric apart at the seam on both ends. You'll see that the end you didn't backstitch will pull apart much more easily, while the end that is backstitched will hold more securely.

Cases where one would expect to backstitch the seams are primarily in structural areas; finishing (top) stitching is also frequently backstitched to prevent the stitches from pulling out.

Similarly, you'll need to understand the purpose of the zigzag stitch. In most cases for home sewing, the zigzag is used to help prevent fraying in woven fabrics; because it's not structural, there's minimal benefit to backstitching at either end, though you may find it easier on some fabrics that are more prone to fraying to start on the fabric and backstitch to the edge before going forward in order to help prevent the fabric from being pulled down through the throat plate.

For further information, I would highly recommend taking a beginning sewing course that can be tailored to your knowledge level. Online tutorials and videos are only marginally useful when you don't have the basic experience expected from them.


Determine kind of jewelry I have found my grandmother's brooch.  She is dead now, so I can’t ask her about it.

Can anybody determine what kind of jewelry this is?  I'm also curious about whether this type of jewelry had or has value of significance, if someone happens to know (yes, maybe it’s cheap, it doesn’t matter).

I have already tried to find it in Google pictures search, got 0 common results.  My grandmom lived in USSR, Italy and France; maybe this information can help somehow.

Some more observations that didn't fit into a comment:

The stones are certainly no precious stones. The color indicates glass stones. If you're willing, you could try scratching the surface in an unobtrusive place like the edge where they're connected to the metal. If you can chip or scratch them with a nail or other sharp object, they are glass stones.
The shade of the metal could indicate silver, but the dark and consistent shadows in all the recesses could mean it's a non-precious metal that was dipped into a color wash to make it look like silver. You can clearly see the color in the areas of the leftmost cross.
All silver (or gold) objects should have a "Hallmark" at the backside, which is a special punch denoting the content of precious metals. If there is no hallmark anywhere on the piece, it is not silver or any precious metal.
If this were a high value artisan work, these hallmarks would be on each of the pendants as well. There would also be special hallmarks indicating the artist.

Example of english silver hallmarks:

All things considered it doesn't give the impression of having any material value. Far more interesting would be the symbolic value, but unfortunately I cannot help you with that. It could be that each of the pendants has a certain meaning that, combined with the other symbols and the place where it was made, could tell a story, commemorate an event, show the association with a certain society or symbolize wishes for the bearer's life.


coffee stencil cutting machine I am looking for a small laser machine to cut coffee stencils for example what you use to decorate your cappuccinos and lattes with chocolate powder. Does anyone know what machines are used and any recommendations? Thanks

An option beyond using a laser would be to purchase a craft cutting machine such as a Silhouette Cameo or similar. It uses a very sharp cutter that is moved over the surface of the material, cutting through to create your stencils. It is quieter and less expensive than a laser cutter. Additionally, a laser machine creates smoke and odors which may be challenging to address.

As Chris suggests, you may find a makerspace with such a device, although they are inexpensive enough to purchase. Laser machines are much more costly.


What are the advantages of watercolour paper over sketch paper? I've been looking around for some paper for watercolour painting. Watercolour paper can be over double the price of sketch paper.

What makes watercolour paper better? Should I invest the money, and buy the watercolour paper, or save my money and take a chance on the cheaper option?

Watercolor paper is, normally, quite a bit heavier and made from cotton. Basic watercolor paper, 140lb, is okay for practice and will tend to buckle unless stretched. The expensive 300lb paper is where professionals tend to land. In any case, the paint pools and absorbs differently than normal paper, and gives you options around blending, washes, etc. that you can't otherwise get.

Traditional paper, made from wood fibers, is much thinner and absorbs the pigment faster, will generally buckle and warp rapidly and is much more likely to rip and tear when wet. It's just not designed for that.

In any event, sheet watercolor paper can be had and you can always cut it into smaller sizes for practice, which is pretty common anyways. The cheaper option will only frustrate and disappoint, it's already a challenging medium, don't make it hard on yourself.


How can I identify/select a foam for stiffening a bag (buying online)? I've started making my own bike luggage.  The first is a simple zipped frame bag, unlined.  Now that's finished successfully I want to make a full length toptube bag.  Because these sit on top of the bike they're usually stiffened with a sort of foam, about 2-3mm thick, to stop them flopping around.  The foam is trapped between the outer and a lining.  I need to buy some of this foam sheet, but the typical EVA foam sheets in craft shops (and kids' craft kits, so I have plenty in lurid colours) is too soft at about the right thickness.
I'm using waterproof fabric (ripstop polyester) and may seal the seams on this bag, but I need non-absorbent foam.  The zips won't be waterproof.
How can I identify a stiffer foam? Densities are given for the better craft foams, but how does that relate to stiffness.  I don't want something actually hard, as I'll only just be able to stand over the bag on the bike; it will be packed with soft stuff  on top.  As a bonus, the foam will provide a bit of insulation for keeping a drink cool.

I've added some links to commercial products for those unfamiliar with the terminology.  The main reason for making them is to maximise the amount I can carry without panniers (bike-packing style; cost is also a consideration.

What you're looking for is foam interfacing (Pellon Flex Foam, Annie's Soft & Stable, Bosal In-r-Form, etc). This is a soft foam material generally about 1/4" (6mm) thick, designed to be sewn into projects like bags, totes, and hats to provide them with a stable structure while still allowing them to flex--it's meant for exactly your intended use. You may feel like it's "too soft" when handled, but when sewn into the shape of your bag, it will hold the form very well (especially once it's filled with other items). As far as your waterproofing concerns, the stitching across the seams should be sufficient to prevent it from getting wet in any weather you'd want to be out in yourself.
The blog Seasoned Homemaker has some information about the three main brands, as well as how to work with this type of interfacing and examples of projects made using foam interfacing for their structure. I've personally used it to make a witch hat (the pattern designer's work is shown here, also using foam interfacing for the structure) and have found it to keep its shape extremely well, even in the flat shape of the hat's brim.


What can I do to stop my colored pencils from falling apart? I have an issue where the point and core of my colored pencils will fall out when using them or sharpening them.

These pieces can be up to an inch long. As they're primarily Prismacolors, they're expensive to wear through so quickly.

Why are they breaking inside and falling out? I take care and sharpen with sharp blades.  They stay stored in their original hard box when not in use, and aren't used often. I feel like they've been cracked inside for awhile, and can't pinpoint how it happened.

But even new ones I've bought individually have done it, too.

What can I do?

Prismacolor pencils are notorious for lead breakage, but the creamy lay down keeps folks coming back. However, there are some things you can do to moderate the problem, in general (I'm going to answer a bit beyond the question).

Pencil Selection

The pencils that tend to break more easily have off-center cores. If you're buying open stock, take a look at the bottom of the pencil and ensure that the core of it is in the center of the pencil body and not askew. None of mine are in this state, or I'd post a picture, but it's really obvious when you see it.

Sharpening Technique

A little counter-intuitive, but I've found that instead of rotating the pencil in the sharpener, going the other way works better. In this scenario, hold your pencil in your "off" hand and then using your normal hand, rotate a very sharp sharpener around. This should be very sharp, the wood should shave off in a long, continuous strip. If it doesn't then it's time to replace.

In addition, don't create a long point. Smaller amounts of exposed core tend to be less fragile and so don't break as often. Find a sharpener that lends itself to that or allows you to control the point.

Fix It Up

Prismas are wax based and can sometimes be fixed by heating the core to fuse it together again. Prismacolor doesn't recommend the microwave, rather a sunny window spot, but many use the microwave. Just keep it short, seconds at a time. After all, you're not looking to make it runny, just softened enough to fuse again.

Handle With Care

Since the lead is fragile, avoiding drops and bangs is a must. The problem, of course, is that transportation to your supplier probably banged and bashed them around, causing the odd one to break even before you got it. To that end, I really recommend going with open stock since you can check the pencils there and, as I noted above, you can confirm that it's not askew.

Change 'em Up

At the end of the day, the price of Prisma feel is the weakness of the lead. If you're reaching the point that it's too much, then there are alternatives. Faber-Castell and Caran d'Ache make great pencils and they don't have the breakage issue. That's partly because they're vegetable oil based rather than wax, but also the lead is bonded to the wood, so even if there is a break inside, all is not lost.

In any event, I have no familiarity with Caran d'Ache pencils to use, but the Faber-Castell Polychromos are really very good and also available in open stock. For me, open stock is a must. So, I have the full Polychromos set and a select bunch of Prismacolors (I generally prefer the white Prisma). They work together just fine.


Gluing pasta to paper? I'm gluing dyed pasta to paper with my son, but it's hard to get it to stick without an obscene amount of glue (Elmer's liquid) or decoupage (Mod Podge).

I'm using cardstock paper, so the glue doesn't soak through or wrinkle. Should I use a different paper with more tooth? Noodles and paper are both fairly smooth. Is there an adhesive that works better for smooth on smooth?

I'm preferably looking for a kid-safe solution, but it's not necessary.

In short

Yellow carpenters/wood glue or white craft glue should both work fine for kids projects. I found yellow glue to be a little stronger.

I think it is important to give the glue time to cure / dry. Following the instructions on the bottle would be important to ensure you are using the glue properly.

When gluing macaroni make sure the entire surface, where the noodle is contacting the paper, is also covered in glue for best adhesion (No exposed ends). You don't want to hide the glue. A good dollop of glue that also surrounds the noodle works best.

  it's hard to get it to stick without an obscene amount of glue or decoupage.

I am actually not sure why you had issues. That being said I don't know what you consider obscene and what glues you used and your specific paper.

Forward

While not a comprehensive experiment as I was testing with products and materials that I had available. I do think between the two of these you should have a good basis for choice though. My breakage tests also are slightly flawed as I don't have the tools to measure pressure exerted nor the ability to make each break with the exact same circumstances. There are other glues that I could have used, however, given my findings, I think the issues would have been the same.

Glues not tested

There are things that I could not test with and choose not use.

I don't think a glue stick or glue dots would be good for this. Hot glue gun could work and even double sided tape. In the case of the latter you might have an aesthetics issue. Gorilla glue or PVA's would also work. Gorilla Glue is an expands while it dries, which I know from experience, so it might not be what you want to use here as it might warp the work.

Test materials and setup

I tested with 3 different paper stocks. Canvas paper, thin cardstock and printer paper. For glues I used carpenters glue (Yellow) and white craft glue. These glues can be considered kid safe and non-toxic. Consult product labels to be sure.

I used brand-less macaroni that I purchased specifically to do macaroni art. The glue was applied with different consistencies to see if the amount of glue was important.

Procedure

For each piece of paper I logically divided it into 8 parts. Each glue was given an indicator box and 3 spots where the glue was applied lightly, heavy and an in-between consistency. The white glue had nozzle so I was able to apply it easily. My yellow glue nozzle broke ages ago so I used a craft stick to apply it. The two below pictures show how much of each glue was applied.

I then proceeded to add one piece of macaroni to each glue site. I made sure that the macaroni was lying flat to the paper to increase the gluing surface area. This picture shows the tests in a completed a drying state. The glue is still wet as this point.

The drying times for each glue was 30-35 minutes. The carpenters glue recommended 24 to allow a full cure. I waited 12 hours before I tested and I think that is fair.

Strength test

I mentioned earlier that this needs to be taken with a grain of salt so I don't suggest using this as a thesis source. This also doesn't cover long term durability1. Here is a picture of the macaronis after I put in effort to remove them all.

From left to right: printer paper, light cardstock, canvas paper

To remove the noodles I used my thumb and pushed from the side of the noodles. There were some that I could not remove like that an had to grab from the end. If the end was not glue I was able to grab under it and pull. If the end were completely glued I would not have been able to do that and it should have been harder to pull off.

Findings

I found the yellow caprenters glue to be better than the white craft glue but not by much. In all cases the glue held and the paper failed. As you can see in some pictures the noodles actually broke. I found the canvas paper to hold onto the noodles better. Likely that is because it was thicker and had a textured surface. The printer paper failed easier. In the printer paper's defense the glue still help to the paper rather well. Still, it was the weakest as I expected it to be.

The glues warped the printer paper significantly and the cardstock somewhat. While I do notice that the other side of the canvas was wet the overall shape was not change i.e. it remained flat.

In short if I was to choose, based on best results, my option would be yellow glue with the canvas paper. I would use enough glue to cover the entire noodle and have enough to sightly pool around it (My heavy option pictured above). The cardstock I used was perfectly fine though.

1: I do have a tangential case I can refer to for this though. 3 years previous to this post I made a anniversary gift for my wife that was macaroni art. I used the exact same macaroni (from the same box) and yellow carpenters glue. This was applied to a small section of wood. My wife displays this in our living room as she thinks its funny. After 3 years none of the pieces have fallen off (This has not been in direct sunlight the entire time). A couple noodles shattered from a fall a while back but the macaroni portion that was glued did not.


How to remove the yellowish color from my old drawings? I have my old (10+ years) pencil art drawings and when I looked at them recently I notice that the paper has yellowed where it is visible.

Is there a way to remove to remove the yellow tint without affecting the drawing?

I don't believe there is a way to remove the yellow staining but there are a lot of methods to keep it from getting any worse.
The reason your paper is turning yellow is because of the quality of paper that was used to make the drawing on. Economical paper is made from wood and not cotton. Chances are you have paper made from a wood pulp. Wood is made up of lignin and cellulose. The yellowing in the result of lignin, still present in the fibres of your paper, oxidizing when exposed to sunlight and air.
And if the paper wasn't washed properly, residual acids from the paper-making process may still be present. These acids help with the oxidation process.
To save your paper I would recommend two things, 1) Neutralize the residual acids and 2) Seal the paper from contact with the air.
Krylon makes a spray (Make It Acid-Free), that helps neutralize the acids. Neutralizing the acids slows down the yellowing and aging of the paper.

Krylon also makes a preservative for protecting documents and photos called PreserveIt.
Neutralize the acids first, then preserve it.
In the future if you want your drawings to last longer (say a couple of hundred years), try using paper that is archival safe or acid-free.

Editor's note: it looks like Make It Acid-Free may no longer be available.  If that's the case, there are a few other similar products, including Archival Mist and Bookkeeper (which is a liquid used in a hand sprayer).  This is provided only as information; no personal experience with the products.


What can I use to cover raised mosaic edges? I purchased a tray with a glass mosaic inlay. The raised edges of the glass pieces are rather sharp and I want to cover them with a clear layer. What can I use to safely accomplish this?

It would help to know the tray material and finish (a picture of the edge detail would be great), and it isn't clear whether you are referring to just the outer edge of the mosaic area or every glass tile, but here are a few ideas:

If the problem is the outer perimeter of the mosaic area, remove the sharp edges with a Dremel tool and diamond disk.  Clamp the tray and tiles in a towel to dampen vibrations.  Use a little water or oil on the spot you're grinding to reduce heat and vibration.  You won't need to remove much to dull the edge.

If the problem is the outer perimeter of the mosaic area, cover the edge with clear silicone caulk.  Clean the surface with alcohol.  Use masking tape to create a clean, straight border close to the sharp area on both sides of the mosaic edge.  Either use your finger to spread the caulk, or dilute the caulk with paint thinner and paint over the sharp edge using a brush.  Remove the masking tape while the caulk is still uncured.  I would be careful using the tray because silicone can often be peeled off surfaces it's adhered to (but if that happens, you can peel it off and replace it).

If the problem is the outer perimeter of the mosaic area, an alternative to a clear covering would be to cover the sharp edge with a "leaded glass" border.  Wrap the sharp edge with a strip of copper foil, then solder the foil.

If the problem is on all of the glass tiles, you could add a layer of clear silicone over the whole surface.  However, sharp edges over the entire surface would indicate that the grout isn't high enough.  You can get color-matched grout at big hardware chains or stores that sell tile.  Add more grout to bring the level up to the top surface so no sharp edges are exposed.  That might also be an option if the problem is only on the outer perimeter; depending on the design of the tray, you may be able to add a border of grout around the outside edge of the mosaic to cover the sharp edges.


How do I finish hand-sewing a seam? I'm mending my (second hand) leather gloves by hand.

My sewing skills are rudimentary, but I like fixing the seams of or patching up clothes every now and then.

However, I never know how to finish up a sewn seam. I usually just keep repeating the last stitch, alternating the angle a little bit, or the direction, in a random fashion (random perhaps because I reason that if it's hard for me to unravel, it must be so too for the thread itself).

I would like to know if there's a proper way to finish sewing a seam.

What I would do at this point with your gloves, is to take the needle and slide it under that last stitch (I took a close look at your pic) leaving a loop behind, then take the needle and slide through that loop to create a knot, you may need to do this twice. Then, I usually push the needle into the material and leave extra thread inside the work, cutting what is super extra or bothersome.
Create the knot

Hide the extra

These stitches shown here are just so I can show a sample, my stitch work is typically better. Though when I darn, I let it get messy. LOL
happy mending sustainability lovers!


What type of paint for mildly flexible plastics? I have a couple of roughly fist-sized plastic† pieces that I'd like to paint (I'll post a pic as soon as I can); preferably with a spray but brush is OK too.
First I intend to lay down a primer (for this material any ABS / styrene primer will do, and I know at least Montana and Tamiya brand plastic primers definitely work). Then I'm going to paint. Solid color, no fine details.
The thing is, this plastic is mildly flexible. It's not straight up bendy or squishy, but it's more like a really stiff rubber, like the kind of stuff you might see used as feet for cheap metal furniture (that's the only example I can think of). It's got a "softness" to it like... you feel like you will be able to bend it but you kind of can't, if that makes sense. So it's not going to be all over the place but it is not perfectly rigid.
Because of that, I'm worried that an enamel paint (it's all I'm really familiar with besides "latex", as I usually work with metal and wood) will start to crack and chip fairly quickly. I've also got my fingers crossed that the primer won't do the same thing, since I have zero experience with it.
Anyways, that was a super long-winded way of saying: What kind of paint can I use? It's got to have some pliability / elasticity when dry, and should at least be compatible with whatever ABS / styrene primers are made out of. Also, the pieces won't be handled super roughly but they will definitely get handled frequently, so it's got to be at least somewhat durable.
Bonus points if it blocks UV, but that's really just icing on the cake (also the primer might, not sure, will have to look it up).

† It's actually resin, not plastic. Specifically it's FormLabs Durable resin off an SLA printer, and the pieces are thick enough to make it rather stiff. But ABS primers are manufacturer recommended so it's simpler just to say plastic here (I mean, it's a polymer at least). It's mechanically closer to a polyethylene or polypropylene plastic, and chemically closer to ABS, than it is to a polyester or polyurethane resin.

Elastomeric paint
 And the asnwer you are looking for...
 Acrylic Paint
Acrylic paint is indeed very elastic, as the comment section points out: It prevents cracking from occurring.

Other Options
There arent really 'other options that doesn't contain acrylic based paints... one of them is called: Urethane, this bad boy is basically modified acrylic paint.
Elastomeric paint Would be your final answer


Do I have to know about muscles and their placements while learning to draw realistic birds? I wish to learn how to draw realistic birds.

I have seen many drawing books talking about muscles in humans, bone structure etc.
I wish to know that to draw realistic birds do I actually have to learn how many muscles they have and where they are placed?

Is that the way to draw realistic birds? or there is some other way?

Knowing the anatomy of your subject will make you a better artist. Here's why...

I can think of four reasons why an artist studies the anatomy of what they intend render into a work of art:

1) Structure
The human eye is very sensitive at identifying shapes and proportions. Get the structure wrong and the eye "will" see it. Knowing how something is put together will make it easier for you to reproduce it during the drawing process. You will also be able to critique your own work and know if the image is working or not.

2) Invention
The artist may not have access to a reference photo of the exact pose they are looking to draw. In this case the artist will need to invent the pose by some means. Look up the stick figures of Terryl Whitlatch, or the maquettes of James Gurney. The stick figure and maquette are both tools available to the artist to help them draw better and be more inventive with the pose of their subject. It takes a solid understanding of anatomy to create a useable tools such as these artists use.

3)Further Learning
When you know the anatomy of the subject it will be easier for you to communicate with others when discussing the subject. Being able to discuss the subject with others will make things clearer in your own mind. As new information comes up you will be better able to catalogue and integrate it with what you already know. Look up Richard Feynman's technique of how to learn anything. Feynman's approach to learning technique works for all subjects, even those subjects important to the artist.

4) Spiritual Empathy
... this gets into some artsy spiritual stuff ...
Learning the anatomy of your subject brings you one step closer in developing your connection to what it is you want to draw. Artists look to put their energy into their works and combine it with the energy of their subject. To be able to detect that energy you need to develop a close relationship with your subject. It through this empathetic connection of understanding that you will be able to connect on a soulful level with the energy and spirit of your subject. Better understanding of your subject (anatomy, physiology, philosophy, behaviour, spirit) will make you a better artist of the subject.


What material should I use for the frame of my lighter-than-air craft? I'm toying around with the idea of making an RC lighter-than-air craft, probably a Zeppelin or Blimp shaped one. I'm pretty sure I'll just use a candle or two to get the lift so it isn't a Hydrogen bomb waiting to go off. Anyway, I've figured that I'll probably wrap it with those thin meat bags at any grocery store or tissue paper to keep most of the air in, and use pipe cleaners fishing line to attach a small box with a candle or two as well as the propulsion system, which will be the circuitry and motors I ripped from a leaky RC boat. With this stuff adding onto the weight, I need a lightweight material to use as the frame.
The material needs to be lightweight, cheap, and preferably purchased from a hardware store like Lowe's or a craft store like Hobby Lobby, Joans, or Michael's, but ordering online is okay.

Balsa wood is likely to provide the best strength versus weight ratio of any building material you'll find. Peter Sripol recently posted a YouTube video of his construction, a rigid airship. Pipe cleaners contain a metal spine adding too much weight, in my opinion.
You may want to consider to use thin lines for suspending the gondola. Spectra fishing line is made of the same material as the plastic bags and is notoriously strong. Extending from that line of thought, you could use either balsa struts (hobby shop sourced) or suspend the gondola with strips of plastic from the bags.
Peter attempted to use helium but found it lacked the necessary lifting power. It appears that he used aircraft modeling tissue to keep the weight down, but I suspect your idea of using super thin plastic is a good one.
I have ordinary small trash bags purchased from a big box store. Only yesterday, I measured the thickness of the plastic at 0.0007 inches, 0.0178 mm which may be the thinnest stuff one could find. The bags are relatively large when slit down one side and the bottom, easier to use than a grocery bag, which I now measured at 0.0008 inches thick. At US$4.48 for a box of 80, it's low cost and readily available. If you require a larger contiguous surface area, the same manufacturer offers an 8 gallon size, but I cannot attest to the thickness of that product. There are no specifications for thickness in the product listing. My figures come from direct measurement with a micrometer capable of reading to one ten-thousandth of an inch.

Home Depot lists 0.7 mil (0.0007 inches) drop cloth but I know that the material is not as durable as the trash bags from WM.
Peter Sripol eventually used hydrogen to get the necessary buoyancy for his vessel and typical of Peter, he ignited the craft during its (obviously) last flight. Hydrogen does not explode, but it will burn as it gains access to oxygen. An explosion would require a suitable mix of oxygen and hydrogen, but your dirigible would/should be inflated with only the one component.
EDIT: I did a quick search for black plastic drop cloth and found I was wrong about the thickness. There's some four mill stuff out there. I suggest black if you don't have an objection, as you'll get solar heating benefit as well. There are also those solar balloons that work on the same principle. Inflate, expose to sunlight, watch them float away!


Basic requirements for paper to practice aquarelle I need to choose which paper to use for aquarelle practicing. I plan to use this paper for practicing only, no need to care about the future of the painting (I can buy different paper for the final versions).

However I do not want it to limit or slow the development of my skills, or start developing skills specific to low quality paper only.

Prices very dramatically. Looks like paper weight is between significant parameters, other parameters may be important. Would it be possible to know the minimal requirements for paper that has no negative impact on the aquarelle  learning process?

When it comes to watercolor, the one place I really recommend avoiding going student grade on is the paper. There are some really excellent student paints, but for paper, meh...

On that front, the biggest names in paper are Arches and Fabriano, but what you're really looking for is 100% cotton rag at 140 lbs in any brand. Some are, really, better than others, but it gets a bit more marginal in the higher end. The key, though, is that is 100% cotton.

So, why? Well, the behavior of the paper is important. Lower quality paper is usually more absorbent, has less sizing, and is much more likely to buckle and warp. In other words, the behavior of the water and paint on the surface is going to be very different when compared to professional grade alternatives. Given that watercolor is already a challenging medium, why make it even harder? Practice on the best you can afford, especially if you want the same techniques to apply to the final copy.


How do I achieve a clean cut of small circles? Using a template for placement, how do I get a clean cut of 1/4, 3/4 and 1 inch holes in fabric? What tool would you recommend?

You have an easy one, I think. The best tool for cutting the holes you describe, in template plastic is a hole punch, also known as a circle punch. A quick search shows that Amazon has all three sizes you describe.
3/4" - EK Tools circle cutter
1/4" - "Conventional" hole punch - 0.25"
1" - Cady crafts Punch
All of the above are amazon links and you can certainly find other resources, but this should give you a path to take.


Blackening steel with oil vs. vinegar - and others? I'd like to finish a lamp I made of brazed chain, and so far my reading has uncovered blackening with oil (linseed or motor), or with apple cider vinegar. What is the difference between these two? The vinegar seems to create a thin layer of Ferric Acetate on the steel piece, but how does the oil quench actually function as far as forming the protective layer?

For indoor use, are there any other finishes I can do at home worth looking into?

Treating with vinegar (or other acids) tends to form a dark grey patina, depending on how it is applied it can also also show variations in shade. More viscous things like mustard and tomato sauce can be dabbled or stippled on to create a distinctly mottled effect. Acids also work well to strip off or at least dull bright zing plating and galvanising.

This finish needs to be dried and sealed with wax, oil, lacquer etc fairly quickly (ie within minutes) or it will start to rust. Also because it is somewhat porous it can be a good base for tinted oils and waxes.

Oil blacking works by polymerising and partly burning the oil. Here the temperature is quite important as the metal needs to be hot enough to blacken the oil without burning it off completely. If you watch the oxide colours as it heats up the point when it goes from deep blue to grey is usually about right. This process is pretty similar to seasoning a cast iron pan. You can either dip the piece in a container of oil or paint it on with a rag (don't use a synthetic brush, it will just melt).

Oil blacking is reasonably stable and doesn't require any additional sealing, although a layer of hard wax, reapplied every so often will make it a bit more durable.

I would recommend using linseed oil or similar rather than motor oil as motor oil (especially used) will contain all sorts of additives that you don't really want to be handling or inhaling. I've found that a mixture of linseed oil and paraffin wax works well.

Another option is to allow the piece to rust and then treat it with a rust converter such as Fertan, these are generally phosphoric and/or tannic acid based and will turn the rust a deep blue/black which can then be sealed with wax, oil etc


When working in a visual medium, how do I avoid incorrect color? Sometimes, when working on a drawing or painting at home, the final result will look incorrect when shown outside or in different light. How can I ensure color correctness when working on my art?

As photographers know, the color of light is usually not white, and when working in your home, you're often working under tungsten bulbs (or similar) which have a warm tone to the light or with fluorescent which have a green cast. Because your brain is pretty good at making what you think should be white look like white, these lights can cause your eyes to see the colors differently and, as a result, change the way you mix or blend in your work.

As with photography, we can control the light we use and select for what our eyes naturally tend to, which is daylight. Where possible, you should light your work with dedicated lamps using daylight balanced light bulbs with a color temperature in and around 5500K. The packaging should specify the color temperature, which is more reliable than if it merely says daylight on the package, so avoid those that don't or that claim a temperature way off that number.

I really recommend getting some decent swing-arm desk lamps and LED bulbs. Not only are these lamps cheaper, but they're usually a lot brighter and much easier to position, especially with easels. LEDs are really efficient and they don't heat you up when working in close quarters, making for a more comfortable experience.


Alternatives to Spirit Gum? Spirit Gum is a brush on liquid adhesive used for attaching prosthetics, and other special effects to the body without harming the skin or the prosthetic. However, stores only carry it around Halloween here. Is there an alternative to it that I could use, that won't damage me or or the special effects, that I could pick up at a crafting store like Hobby Lobby or even a place like Walmart?

Its been a while and I found my own answer.

As an alternative to spirit gum I've found that name brand Eyelash Glue (glue intended for use attaching fake eyelashes) works as an alternative, though the cheap stuff does not. The cheaper Eyelash Glues does't hold up well and the prosthetic is easily pulled off with the most minimal of force, making it a bad choice if one intends on wearing the prosthetic anywhere that there is a chance it will be brushing up against anything (like walls, tree branches, etc.)

The best alternative I've found is Nail Glue (Glue intended for attaching fake nails). The nail glue is relatively cheap. It holds as well as spirit gum but it is also just as easy to remove the prosthetic once you're done as it is when using spirit gum. It does not appear to have damaged the prosthetic either.

Both Eyelash Glue and Nail Glue are readily available where ever make up is sold, including Walmart, Target, CVS and Walgreens.


What can I do to reduce pain while crocheting? I understand that this will happen regardless with this kind of relative motion. Especially with smaller models where your hands are constantly trying to keep proper tension of the yarn.

Still though, this is something that all crocheters must deal with. I suppose the easiest thing to do is take breaks but I wonder if there is more to it than that.

What, as a crocheter, can I do to help mitigate pain and cramping that I get while working? Perhaps this would apply to knitting as well.

So I'm a big knitter and crocheter and a musician with tendinitis for the past 20 years. Aside from the standard advice (NSAIDs, massage, etc) there are a few things that you can do to mitigate the situation.

First, make sure that the amount of pressure you're using is the bare minimum amount possible. It may actually take some time to retrain your hands, but it's worth taking the time to do it. You may want to slow down a little bit, focus on using as little effort as possible, and then speed up gradually using the same amount of pressure.

Second, with knitting and crochet you can also mitigate repetitive strain by making your movements as small as possible. This of course has an added bonus of making your stitches a bit faster.

Third, you may want to experiment with different styles and materials of hooks/needles. I can barely use a standard boye aluminum hook, but I find that when the hook has a nice handle, it actually helps a lot. The lightness of the hook and the resistance of the material will also make a difference.

The last point of advice that I have for you is that if you start to feel any pain at all, stop, stretch, and give yourself a few minutes before you go back to it. It might be kind of tedious at first, but if you avoid damage while retraining your muscles to move lighter, smaller, and with less pressure, you should be able to retrain yourself so that long term you can crochet without any pain at all. It took for me about 3 months to really fully go through the retraining, but it's made a HUGE difference in my ability to do all of the things that I actually want to do.


Material that can be cut / carved and doesn't react with silicone I'm currently experimenting with making silicone molds for casting. I'm not interested in the commertially available molds and want to make my own. For financial reasons I use the cartridges of transparent silicone commonly available in home construction stores.

In my first experiment I wrapped a plastic bead in silicone to make a mold. The silicone took on the color of the bead, so it clearly reacted and melded with the plastic. I was unable to remove the bead from the silicone and threw the whole thing away.

Next I carved an object out of candle wax and covered that in silicone. When the silicone was cured, the object was covered by a thin layer of very white wax, almost like a frosting. After removing the object from the mold the white residue stayed behind and the planes of the object were not cleanly molded and full of imperfections.

Then I tried a special "casting putty". It is not polymer clay like Fimo, but a putty designed to seal gaps in molds before casting. It gets soft and malleable at body temperature and hardens when cooled down. Again, the silicone melded with the putty. I haven't tried polymer clay because I noticed that I couldn't make the planes of the putty object as smoth and shiny as I wanted.

I wasn't expecting silicone to react and meld with materials, least of all candle wax.

Is there a material that can be easily cut and carved into clean, shiny planes but that does not react with silicone? Or do I have to coat my objects in another material to protect them from the silicone?

Cover the object in petroleum jelly (aka Vaseline) first, you may also try adding paint thinner to it, to make the coating smoother.

Using different types of construction silicone may give different results. Some of these contain glue and other components that make the cured silicone stick better to different surfaces. So I guess the simplest and cheapest neutral silicone is the best.

EDIT: some say that adding the corn starch to silicone makes the molds dry faster. Not sure if it makes the silicone less liquid though.


Why are parallel lines in the real world not drawn parallel as they head to the vanishing point? I'm working through Perspective Made Easy, and the introductory section about parallel lines has thrown me, specifically pages 23 through 25. The diagrams are especially confusing to me; for example, on page 24 it says: "As he raises his eyes and looks fifty feet in front of him he sees the same width of tracks but within a much narrower area", but the cone of his vision is not narrower, merely stretched longer:

Based on the description, I would either expect the man's vision to be far broader than the tracks (especially so for the more distance piece), or perhaps the distant piece of track narrower than the closer piece (although, physically speaking, we know this isn't the case).
I've obviously observed the phenomenon of scale being affected by distance in real life, but I'm trying to articulate the rules behind this so I can understand and implement them better in art practice, and diagrams/phrasing such as the above are confusing me more than they are helping. Can someone rephrase this or draw up a better illustration? It's left me even more confused about perspective than my default instincts, so I'd really appreciate the clarification.

I will preface my response with a cautionary warning that I am an engineer by profession, so I am somewhat naturally inclined to use optics/physics and math to illustrate my point. Hopefully I'm enough of an artist to actually be able to illustrate this sufficiently well. Now, onwards!
A person's field of vision can be described as the "cone" radiating out away from your face that describes the area you see as you look straight away from you, with the tip at your face and the cone expanding wider as you look farther away - that is, the farther away you look, the wider your horizontal field of view. (So you are correct here - the person's field of view is much wider than it appears in the book's diagram. Those lines extending from their head should continue beyond the tracks.)

(Source: Rohit Grover's answer on Quora)
For the calculations, I'll use 120 degrees as the angle of the field of view, which includes peripheral vision. I'll also assume your field of vision of the ground is approximately the same as your field of vision at a horizontal distance straight ahead of your face (instead of looking slightly downward toward the tracks on the ground) - however, if I did include the vertical component, your field of vision would be slightly wider.
For reference, I read up on some of the answers to a similar question that was asked on the Physics StackExchange.
Basically, as the railroad tracks lead away from you, the width of the tracks take up a smaller portion of your field of view, which creates the impression that the space between the tracks becomes smaller as it moves away from you. At the farthest point that you can see, the tracks take up such a small portion of your field of view that they appear to converge into a single point.
To illustrate this a little more, I have provided a simple diagram and some calculations below.

(Source: My own skills in MS Paint.)
The black parallel tracks are the railroad tracks. On the left is the viewer (you), represented by a squashed oval, who is looking down the tracks. Your field of vision is illustrated by the red lines, which create an approximately 120-degree angle, beginning at the viewer and extending outward. 120 degrees was wider than I had anticipated, so you'll have to imagine the lines extending beyond the image.
Using some basic geometry, we can calculate the width of your field of vision at different distances away from you. The standard gauge (width between the rails) of a US railroad track is 4 ft 8.5 in (source)- I'll round this to 5 ft to simplify the calculations.
Let's say Point 1 (light blue) is 7 ft away from you. Using some trigonometry, we can approximate the width of your field of view at 7ft away. One half of the triangle forming your field of view is, quite conveniently, a 30-60-90 right triangle, as shown below.

Since this triangle is half the field of vision, the full width across the horizontal field of vision at 7 ft away from you is roughly 24.24 ft. That means the percent of this horizontal field of vision that is occupied by the 5-ft distance between the railroad tracks is just over 20%.
Let's say Point 2 (green) is 20 ft away from you. At this distance, your horizontal field of vision is 2 x 20 x sqrt(3) = 69.28 ft. The 5-ft distance between the tracks is now 7% of your horizontal field of vision.

Point 3 (yellow green) is roughly 40 ft away from you. Here, your horizontal field of vision spans 2 x 40 x sqrt(3) = 139 ft. The 5-ft space between the tracks is now a mere 4% of your field of vision.

Due to the Earth's curvature, the railroad tracks will eventually disappear over the horizon. Assuming you're an average-sized human, you can see about 3 miles (15,840 ft) away until something vanishes over the edge of the horizon (source). At this distance, your horizontal field of vision is now a whopping 2 x 15840 x sqrt(3) = 54,871 ft. At the horizon, the 5-ft space between the rails has now shrunk to only 0.0097% of your horizontal field of vision.
If your eyes were sharp enough, you could hypothetically still see that gap between the rails. If they're not, from your perspective the 5-ft space between the rails will have essentially shrunk to nothing, and the rails will appear to converge to a single point.
So... are your eyes sharp enough to still see that gap?
For the average person, the angular resolution of the eye is approximately 1 arcminute, which means humans can distinguish things that are 30 cm apart at 1 km away. If we scale this to the width of the railroad tracks (4 ft 8.5 in, or 56.5 inches), you won't be able to see the space between them after about 5400 yards, or 3.07 miles. Which, quite coincidentally, is almost exactly the distance to the visible horizon.
In summary:

Parallel lines appear to converge toward each other because as they retreat into the distance, they take up a smaller portion of your field of view.
Parallel lines appear to meet in the horizon because our eyes can no longer distinguish the space between them at that distance.

I hope this helps! =)


Can any leather crafters tell me what tool this is? My friend began taking up leatherwork. This tool came in a kit he bought. We know what everything else is except for this piece, and a reverse Google image search came up short. Just showed us bullets and pencils. Anybody know what this is and what it's for?

Awls are typically used for punching holes into objects, awls come in different styles. This one in particular, if you look at the back end, looks very durable, and able to be hammered on the back without issues. So it is able to push through thick leather easily.
Standard image of an awl:

Awl being used to punch hole:

Awl being used in practice to lace leather:

Sources:
https://hausoftools.com/blogs/news/tools-of-the-trade-tools-for-leather-working
https://www.instructables.com/how-to-prepare-leather-for-sewing/


How can I repair a plaster sculpture? My current sculpture encountered an accident and the Giraffe lost a leg.

How can I repair the leg? I've got plenty of plaster mix and epoxy, but not sure if applying either will work.

The sculpture was unfinished. I'd prefer a method that allows me to continue finishing its details.

I would make a slip, made from the same plaster as the model was made from, and use the slip to "glue" my two pieces together.

Scoring the inner surface slightly giving the slip a bit of a roughened surface to bind to.

When the two halves are brought together you want to see the slip forced out of the joint. Just wipe off the excess with a damp cloth.

If you don't see the slip being squeezed from the joint then you didn't use enough.

By using the same material to bind the pieces together as what the sculpture was made from you won't have to worry as much about discolouration.

Hard part will be holding the two pieces together while the slip dries.

Don't use masking tape! Masking tape will stain your material.

If you do go the tape route, use a good quality painters tape as you can leave it for hours, or days, and not worry about it leaving any residue behind.

Here's a quick sketch of the steps I would take.

Find a narrow headed screw (such as a flooring screw) and measure its length. We will call that length "d".
Drill a pockets slightly larger than the head of the screw into both halves of the plaster cast to a depth of 1/2 d.
Fill both drilled pockets with your slip compound.
Insert the screw into the pocket such that half the length of the screw is sticking out the top of the cast. The part that is sticking out will what will hold the other part of your cast.
Align and bring together both halves of the broken cast. And squeeze them together. You want to see the slip squeezing out of the joint. If you don't them you did not use enough.
Once the pieces are together you can use a damp cloth to wipe the excess slip from the surface.
Bind the two halves and allow to dry.

I'm not sure how big of a piece we are talking about in your case. If it's a lot smaller then instead of the screw you could use a piece of aluminum wire to act as the screw. Remember to form the wire into a loop at both of its ends. Once the slip dries the loops will be anchored into the dried plaster and keep the two pieces from pulling apart.


What's the difference between drawing paper and regular paper? Supply stores sell drawing paper, sketching paper, and all sorts of bound pads and books of the same.

What makes this paper different than regular notebook or printer paper? How is it better suited for drawing?

What makes the charcoal paper different than drawing paper, when both are used for drawing?

TL;DR:  Generally speaking, printer paper is not designed to last long, and is intended to hold ink rather than graphite, charcoal, paint, etc.  The same is more or less true of notebook paper.  Printer and notebook paper have very little tooth (roughness); lack weight (i.e., the sheets are thin); and have relatively high acid content, which means they will yellow and become brittle over time.

Different Kinds of Drawing Paper:

The main differences:  Tooth and Weight

Weight:

"Weight" is basically (as the term implies) a measure of how thick and heavy each sheet of paper is.

  Thicker or heavier papers can handle more water or paint without buckling, curling or falling apart. Traditionally, papers are measured by the weight in pounds of one ream, approximately 500 sheets. If a paper comes in different sizes, its weight will vary even though the thickness has not changed. Each paper type uses a certain size as its "standard." A ream of standard 22" x 30" watercolor paper (500 sheets) would weigh 300 lbs. The very same thickness paper in a 40" x 60" sheet would have a weight of 1,114 lbs. for the ream of paper. Its weight changed due to the size of the sheets, not the paper's thickness, but the paper is still designated as 300-lb.

  The inconsistency of this traditional method has led to the use of metric measurements or grams per square meter or gsm. When paper is measured in gsm, its weight will not change with the size of the sheet. The same 22" x 30" sheet of watercolor paper described above would weigh 640gsm, meaning that a square meter of this paper would weigh 640 grams. Larger size sheets of that same paper, like a 40" x 60" size sheet, also would weigh 640gsm. While different sizes, the square meter remains constant, as does the thickness of the paper.
  -  Dick Blick

And:

  Weights (relating to thickness) of paper are standardized and defined by the International Organization for Standardization and are often listed in grams per square meter (gsm), or in pounds, the standard of measurement more familiar to most artists in the U.S.  Following are some of the most common weights of paper found in sketchbooks and drawing pads (all measurements are approximate):

  25 lb (approx 40 gsm):  tracing paper
  30-35 lb (approx 45-50 gsm):  newsprint
  50-60 lb (approx 75-90 gsm):  sketching or practice paper — thick enough to work on with pencils, charcoal, or pastels, but usually too thin for ink or most markers, which may bleed through.
  70-80 lb (approx 100-130 gsm): drawing paper suitable for finished artwork in most media.  Paper any lighter than 70lb will usually be thin enough to see through to drawings or materials underneath.
  90-110 lb (approx 180-260 gsm):  heavy-weight drawing paper, bristol, multi-media papers.  Weight in this range is similar to card stock or light poster board.
  Heavier papers, up to 140 lb (approx 300 gsm) or more, are most often used for painting rather than drawing.  When found in sketchbooks, they are usually rougher papers intended as watercolor journals or to remove for painting on individual sheets.
  -  Muse Art and Design

And:

  Sketch paper is the thinnest, lightest paper, varying from 30 to 60 lbs. It isn't meant be used for finished drawings, as most will discolor and degrade quickly. However, it's economical, and perfect for short studies, thumbnails, compositional sketches, and working out ideas.

  Watercolor or printmaking paper has to be the thickest, heaviest paper because it must withstand the moisture from the water media applied to it. It usually weighs between 90 and 140 lbs. (The smoother, hot press watercolor papers can be great for drawing, also!)

  Graphite or charcoal drawing paper doesn't need the durability of watercolor or printmaking paper, but is heavier than sketch paper. It usually weighs between 70 and 100 lbs. The weight you choose should depend on how you work with your medium.
  -  Drawing Source

Tooth:

"Tooth" is a measure of how rough or smooth the paper's surface texture is.  The more tooth a paper has, the rougher it is, and the better it will take soft art media like charcoal and pastels.  The less tooth it has, the smoother it is, and the better it will be for fine detail work, harder graphite, pen and ink, etc.  Wet media (ink, watercolors, etc) will be more likely to bleed on a toothier paper;  dry media (charcoal, pastels, etc) will be more likely to slough off of a paper with less tooth.

  Surfaces are described as having more or less “tooth,” or roughness in texture. The more toothy the paper, the rougher its surface.

  Rougher surfaces are generally found more in thicker papers. Thick, toothy surfaces hold on to more of the drawing or painting medium and are better for high contrast and lower detail works. Toothier papers are well suited to charcoal, crayon and pastels, ink washes and watercolor, or any work that utilizes the texture of the paper for aesthetic effect.

  Smoother surfaces take up less media and are better suited to more detailed work. Very lightweight papers like tissue paper, and lightweight sketch paper are usually smooth, but thicker papers like bristol and some painting paper are also smooth. Smoother surfaces are ideal for graphite pencil, colored pencil, and ink pens. Smoother papers are also more likely to be bleedproof, meaning that ink or color washes won’t spread and “feather” across the surface.
  -  Muse Art and Design

And:

  Rough paper is chosen for its definite texture. It is the natural result when a sheet is allowed to air dry without smoothing or pressing. Rough surface paper is a good choice for transparent watercolors used in a bold and immediate style, as it allows the pigment of color washes to settle into the hollows of the paper. Pastel artists also generally prefer a paper with "tooth" or texture to grab onto the pastel pigment.

  Cold Press paper, which is the most popular and versatile, has a slight texture. Handmade papers achieve this by re-pressing a new wet sheet, which smoothes the surface to some degree. Machine-made papers get a similar effect by placing the wet sheets between cold metal rollers.

  Not/Cold Press: A "Not" sheet means it is "not hot press," and the term is often used instead of cold press.

  Hot Press paper is very smooth. It is made by running a freshly formed sheet through heated metal rollers or plates. Much like a clothes iron, this smoothes out any texture left by the earlier stages and creates a flat, hard, featureless surface. A good choice for highly detailed illustrations, it is also used for printmaking, etching, drafting, sketching and drawing.
  -  Dick Blick

Secondary coniderations:  Fiber and Sizing

Fiber (and acidity):

  Paper is made from a variety of plant sources. Whether the fibers come from cotton or other plants such as linen, flax, jute, hemp, bamboo, rice straw or rattan, they all provide cellulose fibers or plant cells of varying dimensions. A sheet of paper is basically a thin layer of mingled cellulose fibers. Most commonly, three types of fibers are used to produce papers for drawing and painting: cotton, cellulose and a combination of fibers.

  Cotton papers, made from the longest cotton fibers, are generally considered the highest quality. They are referred to as being 100% cotton rag and can handle heavy erasing and working without tearing or showing wear. High-quality 100% cotton paper can last more than 100 years. However, not all cotton papers are the same. Those made from the lesser-quality, shorter cotton fibers can get fuzzy with reworking.

  Cellulose papers are usually made of wood pulp and naturally have an acid content that will destroy the paper over time. The more acidic a paper is, the shorter its life expectancy. Buffers can be added to make the paper neutral.
  -  Dick Blick

And:

  Many papers are acid free. This designation means that the paper has a neutral pH (around 7). Acid-free papers should be selected for work intended to last for long periods of time because papers with higher acid content will deteriorate much faster. For most cellulose-based papers, acid-free also means that lignin and sulfur have been removed from the paper. These are the ingredients in wood-based papers that fade ink and turn paper yellow over time.

  Cotton and cotton-rag paper do not contain cellulose and are naturally acid-free. Cotton-based papers are also stronger, often thicker, hold up better to a lot of erasing, and perform well for wet media such as watercolor or ink washes. Cotton is often blended with cellulose to add strength and durability to paper. Premium archival papers will often list a ratio of cotton and wood fiber.
  -  Muse Art and Design

And:

  pH neutral means that the paper had a neutral pH (7) at the time that it was made, but may still contain ingredients that can become acidic over time (for example, the size used to seal the paper).

  Acid free means that nothing acidic (and nothing that can become acidic) was introduced to the paper at any point in the paper-making process.

  Some manufacturers (such as Strathmore) take further precautions and make paper at a slightly basic pH of 7.2 to 7.5.  This provides an alkaline buffer to help counter anything acidic that it may come into contact with.
  -  Drawing Source

And:

  The rate and severity of deterioration result from internal and external factors: most importantly, the composition of the paper and the conditions under which the paper is stored.

  Paper is made of cellulose -- a repeating chain of glucose molecules -- derived from plant cell walls. One measure of paper quality is how long the cellulose chains, and subsequently the paper fibers, are: long-fibered paper is stronger and more flexible and durable than short-fibered paper.

  In the presence of moisture, acids from the environment (e.g., air pollution, poor-quality enclosures), or from within the paper (e.g., from the raw materials, manufacturing process, deterioration products), repeatedly cut the glucose chains into shorter lengths. This acid hydrolysis reaction produces more acids, feeding further, continued degradation.

  Mechanical pulping produces paper with the shortest fiber length and does not remove lignin from the wood, which promotes acid hydrolysis. Newspapers are printed on mechanically pulped paper. Chemical pulping removes lignin and does not cut up the cellulose chains as thoroughly as mechanical pulping, yielding a comparatively stronger paper, but which is still not as durable as rag paper.

  Wood pulp paper from before the 1980's also tends to be acidic from alum-rosin sizing (added to the paper to reduce absorbency and minimize bleeding of inks), which, in the presence of moisture, generates sulfuric acid.

  Acids also form in paper by the absorption of pollutants -- mainly sulfur and nitrogen oxides. Book leaves that are more brown and brittle along the edges than in the center clearly illustrate this absorption of pollutants from the air.

  Research by the Library of Congress has demonstrated that cellulose itself generates acids as it ages, including formic, acetic, lactic, and oxalic acids. Measurable quantities of these acids were observed to form under ambient conditions within weeks of the paper's manufacture. Moreover, paper does not readily release these acids due to strong inter-molecular bonding. This explains why pH neutral papers become increasingly acidic as they age.
  -  U.S. Library of Congress

Sizing/Absorbency:

"Sizing" is an additive that makes the paper more resistant to moisture.

  Papers intended for wet media (paints or inks) are made with sizing, a starch or gelatin that is either included in the paper pulp during the paper-making process, or is applied to the surface of the paper.  Sizing prevents liquid from absorbing too quickly into the paper, allowing some working time to lift, lighten, or move paints or inks by applying more water.  Sizing also helps protect the paper from getting too soggy, which can result in tearing and wrinkling.  Sizing can also help prevent finer ink or paint lines from spreading and feathering.  Sketchbooks intended for wet media should indicate on the cover that the paper is sized.
  -  Muse Art and Design

And:

  Sizing is added to make paper more water-resistant. It keeps the paper from absorbing too much moisture or pigment and helps to keep watercolors or inks brilliant. It also keeps lines and edges looking crisp. It is less important for papers used for dry media. Sizing also can factor into a paper's archival qualities - whether it will sustain or deteriorate over time.

  Internal sizing is added while the paper pulp is still in a liquid state and is maintained in the matter of the paper.

  External, Surface or Tub sizing is applied to the surface of the paper after the sheet is formed and dried. Some paper is both internally and surface-sized.
  -  Dick Blick

Other considerations:

Binding:

Sometimes a matter of mere personal preference, sometimes a matter of necessity, "binding" refers to how - and whether - the sheets of paper are connected to one another:

  Hard-bound sketchbooks have a hard cover and a sewn joint, just like a hard-bound book. These sketchbooks generally contain medium weight paper, about 70 lb. Hard-bound sketchbooks are the toughest and sometimes the expensive. They take more wear and tear, and generally survive longer than spiral or tape-bound books. Depending on the quality and method of binding, hard-bound sketchbooks often do not lay flat when opened all the way, so they can be difficult to use for larger drawings or for writing. Hard-bound sketchbooks are also less likely to have perforated pages, so they’re better thought of as real archival sketchbooks.

  Spiral-bound sketchbooks sometimes have hard covers but their covers often consist of a hard back cover and a thick paper front. Because of this construction, spiral-bound books are a little less hardy than hard-bound sketchbooks. Spiral-bound sketchbooks open flat when put on a surface, so they can be good for ink and paint washes. Spiral-bound sketchbooks often have perforated pages, so pages are easy to remove and have a clean edge for presentation, duplication, mounting, or framing

  Tape-bound sketchbooks generally have fewer pages than hard-bound and spiral-bound sketchbooks and do not have substantial covers. Tape-bound sketchbooks are not rugged, long lasting sketchbooks. Sketchbooks bound in this manner come in a wide variety of surface types and weights, ranging from very thin tissue and tracing paper to heavy bristol and vellum papers. Sometimes, tape-bound sketchbook pages are perforated, but often the pages are held in by a line of adhesive so it is not difficult to pull them out.
  -  Muse Art and Design

And:

  Single sheets are a great way to experiment with a limited quantity of paper. They will often require stretching and taping to remain flat if wet media is being used.

  Blocks are a stack of paper glued or bound together on all four sides and mounted on a backing board. A block keeps the paper stretched as you paint. Once the painting is dry, the sheet is removed by inserting a knife between the sheets and gently breaking the binding. Blocks are a good choice for working wet, outdoors or while traveling. The disadvantage is that you can only use one sheet at a time.
  -  Dick Blick

Printer Paper:

Compared to drawing paper, printer paper is cheaper, lower weight, more acidic, has less tooth, can't handle wet media, doesn't take much dry media, can't handle wet media, and is generally crappy in every important respect.  It works for doodling, but if you want to make something really beautiful and long-lived, you need quality paper.