<p>You could look up a <a href="https://www.pivotpins.com/products/bc-clevis-pins-with-grooves.html" rel="nofollow noreferrer">Clevis pin</a> with one groove.<br>
You could look up a <a href="http://technifast.co.uk/clevis-pins" rel="nofollow noreferrer">Clevis pin</a> with a hole for a split pin.<br>
Perhaps a <a href="https://www.ondrives.com/303-stainless-steel-shoulder-screws#/pageSize=25&amp;orderBy=5&amp;pageNumber=3" rel="nofollow noreferrer">Shoulder screw</a> with a ground shank and a low profile head.<br>
Use a plain rod with <a href="http://www.bakfin.com/starlock/metric-capped-roundshaft.html" rel="nofollow noreferrer">Dome caps</a> if you will not need to remove often.<br>
If available an internal threaded <a href="https://www.unicorpinc.com/metric-standoffs.htm" rel="nofollow noreferrer">Standoff</a> would work.<br>
A <a href="https://www.ondrives.com/carbon-steel-slotted-spring-pins" rel="nofollow noreferrer">Slotted spring pin</a> may work if the hole dimensions are suitable.    </p>

<p><strong>EDIT:</strong><br>
You could also cut the grooves yourself pretty easily.  Cut a section of 8mm rod to length and mount it into a drill chuck so it stick out 2-3mm 1/8". Hold a hacksaw at the edge of the chuck and run the drill for a minute with gentle pressure, try hacksaw on other side or reverse direction if nothing is happening.<br>
A hardened rod will cut better with a Dremel type cut-off disk</p>

<p><a href="https://i.sstatic.net/fzlGw.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/fzlGw.jpg" alt="enter image description here"></a></p>

CC BY-SA 3.0
2017-01-17T13:07:24.793Z
2017-02-12T13:16:14.347Z
2017-02-12T13:16:14.347Z
KalleMP
<p>I have finally received a reply from my supplier, which backs up StarWind's answer:</p>
<blockquote>
<p>I did not use a rod with grooves for retaining rings.</p>
<p>I used bolts and nuts with a thin head.</p>
</blockquote>
<p>Doesn't really answer my question though, as I really rather hanker after the 8 mm smooth rod with the circlip grooves.</p>

CC BY-SA 3.0
2017-01-17T04:08:17.003Z
2017-01-17T04:08:17.003Z
2020-06-18T08:29:41.667Z
Greenonline
<p>Oh fascinating. It took me a while to figure out what exactly that is. It is a smooth rod used as the idler for the X belt. </p>

<p>What I would do is get a bearing / wheel. Take a thicker screw, nut and washer. Put the idler / bearing / wheel into the slot, then fit the screw / nut. Should work without any issue!</p>

<p>That said they likely had some sort of special fitting etc. Doesn't matter so long as the belt can move without wearing. </p>

<p><a href="http://www.thingiverse.com/thing:157303" rel="nofollow noreferrer">This Thingiverse</a> does exactly what I am thinking.</p>

<p><a href="https://i.sstatic.net/x7BkI.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/x7BkI.jpg" alt="bolt example"></a></p>

<p>As you have a low profile need due to the interesting design I came across <a href="https://www.belmetric.com/index.php?main_page=product_info&amp;products_id=4030&amp;cPath=3_569_718&amp;gclid=CM6Pifm5rtECFVK5wAodMq8HLg&amp;zenid=9o5khnodisqvndhvoejl6b6t40" rel="nofollow noreferrer">this</a>. a TNF8 - Nut Sert - Flanged/Ribbed.
<a href="https://i.sstatic.net/Z4gAg.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/Z4gAg.jpg" alt="enter image description here"></a></p>

<p>Or you may just need a standard low profile nut. Not like you need it to do more than hold it in..
<a href="https://i.sstatic.net/szyvM.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/szyvM.jpg" alt="enter image description here"></a></p>

CC BY-SA 3.0
2017-01-06T12:30:52.093Z
Thanks for the reply. The smooth rod is not the idler, per se, yet it _is_ the axle for a 608zz bearing. I have updated my question, with additional images and a link to an assembly video, that I found on YouTube. I had considered using an M8 Bolt, however, space is rather tight, and the head of the bolt could interfere with both the Z-axis 5 mm smooth rod and the M5 threaded rod (or M8 lead screw). Hence the requirement for the grooved rod, and the circlips, as this requires less clearance.
Greenonline
CC BY-SA 3.0
2017-01-06T15:52:12.917Z
Yeah that's exactly what I thought it was 
MakerModder
CC BY-SA 3.0
2017-01-06T21:22:02.777Z
Yeah that is a tight design. Contacting the MFG for the part / the seller is best.. Else you will be Epoxying that thing together...
MakerModder
CC BY-SA 3.0
2017-01-06T21:23:16.473Z
You know they do sell thin nuts. Edited answer for something that may help
MakerModder
CC BY-SA 3.0
2017-01-06T22:35:23.090Z
-The nut sert looks promising. :)
Greenonline
CC BY-SA 3.0
2017-01-06T22:40:30.677Z
I do hanker after that special short rod though. I have contacted my Polish supplier, but as I mentioned, they aren't very communicative. I may need to try to contact the Spanish chaps who designed the idler, if/when I manage to locate them.
Greenonline
CC BY-SA 3.0
2017-01-05T19:36:34.127Z
2017-01-06T21:25:09.537Z
2017-01-06T21:25:09.537Z
MakerModder
<p>Here is the X-axis of the P3Steel:</p>
<p><a href="https://i.sstatic.net/xuYOq.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/xuYOq.jpg" alt="X-axis arm of P3Steel" /></a></p>
<p>The X-axis idler end of a P3Steel printer, employs an 8 mm diameter rod for the axle on which a 608zz bearing is mounted for the GT2 belt. This 8 mm rod is approximately 20 - 24 mm in length, with grooves at either end, for circlips.</p>
<p>A photo of the assembled idler, with the rod and circlips highlighted:</p>
<p><a href="https://i.sstatic.net/1qJ06.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/1qJ06.jpg" alt="X-axis idler end" /></a></p>
<p>My question is: Does this part need to be custom made?</p>
<p>The short rod didn't come with the frame kit that I purchased (nor was it listed in the parts list, or shown in the photo of the parts - so it not as if it was omitted with my order). I have searched on eBay for it, using various search terms, and I am unable to find one. As I was not trained in mechanical engineering, I am not sure if this part has a special name, or is it just called a &quot;smooth rod, with grooved ends&quot;? I have also done a fair amount of googling, and although I have found some people who have constructed this particular frame, no one makes mention of this axle, nor any difficulties in sourcing it.</p>
<p>I have contacted the supplier of the frame, <a href="http://www.ebay.co.uk/itm/Frame-Prusa-I3-P3Steel-v4-0-RODS-/182361720200?" rel="nofollow noreferrer">Frame Prusa I3 P3Steel v4.0 +RODS</a>, and I am awaiting a reply.</p>
<p>This missing part is holding up my build progress - I already have the 608zz bearing and circlips.</p>
<hr />
<h3>Additional images</h3>
<p>This image shows the &quot;exploded view&quot; and the 8mm rod can be clearly seen:</p>
<p><a href="https://i.sstatic.net/JPjQR.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/JPjQR.jpg" alt="Exploded view of the parts of X-axis idler" /></a></p>
<p>Here are images of the assembled idler, showing the bearing inside -</p>
<p>Front view:</p>
<p><a href="https://i.sstatic.net/c63fV.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/c63fV.jpg" alt="Front view" /></a></p>
<p>Side view:</p>
<p><a href="https://i.sstatic.net/2Nggu.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/2Nggu.jpg" alt="Side view" /></a></p>
<p>This images are a little blurry, as they are screen shots taken from the video, <a href="https://www.youtube.com/watch?v=iDtDiW0kTSc" rel="nofollow noreferrer">I3 Steel CORDOBESA con extrusor/with extruder</a>.</p>

CC BY-SA 3.0
2017-01-05T19:07:05.730Z
It almost looks like a rivit..
MakerModder
CC BY-SA 3.0
2017-01-05T19:11:21.743Z
@StarWind - I can see what you mean, but it's not a rivet, there are circlips on the front and (I assume) the rear also. I'll try to find a better photo - that picture was a screenshot from a YouTube assembly video.
Greenonline
<printer-building><p3steel>
Is the 8mm x 20mm bearing axle for the X-axis idler (of a P3Steel) a custom part?
Greenonline
# Is the 8mm x 20mm bearing axle for the X-axis idler (of a P3Steel) a custom part?

(Asked by: username_0 on 2017-01-05)

Here is the X-axis of the P3Steel:

[![X-axis arm of P3Steel](https://i.sstatic.net/xuYOq.jpg)](https://i.sstatic.net/xuYOq.jpg)

The X-axis idler end of a P3Steel printer, employs an 8 mm diameter rod for the axle on which a 608zz bearing is mounted for the GT2 belt. This 8 mm rod is approximately 20 - 24 mm in length, with grooves at either end, for circlips.

A photo of the assembled idler, with the rod and circlips highlighted:

[![X-axis idler end](https://i.sstatic.net/1qJ06.jpg)](https://i.sstatic.net/1qJ06.jpg)

My question is: Does this part need to be custom made?

The short rod didn't come with the frame kit that I purchased (nor was it listed in the parts list, or shown in the photo of the parts - so it not as if it was omitted with my order). I have searched on eBay for it, using various search terms, and I am unable to find one. As I was not trained in mechanical engineering, I am not sure if this part has a special name, or is it just called a "smooth rod, with grooved ends"? I have also done a fair amount of googling, and although I have found some people who have constructed this particular frame, no one makes mention of this axle, nor any difficulties in sourcing it.

I have contacted the supplier of the frame, [Frame Prusa I3 P3Steel v4.0 +RODS](http://www.ebay.co.uk/itm/Frame-Prusa-I3-P3Steel-v4-0-RODS-/182361720200?), and I am awaiting a reply.

This missing part is holding up my build progress - I already have the 608zz bearing and circlips.

---

### Additional images

This image shows the "exploded view" and the 8mm rod can be clearly seen:

[![Exploded view of the parts of X-axis idler](https://i.sstatic.net/JPjQR.jpg)](https://i.sstatic.net/JPjQR.jpg)

Here are images of the assembled idler, showing the bearing inside -

Front view:

[![Front view](https://i.sstatic.net/c63fV.jpg)](https://i.sstatic.net/c63fV.jpg)

Side view:

[![Side view](https://i.sstatic.net/2Nggu.jpg)](https://i.sstatic.net/2Nggu.jpg)

This images are a little blurry, as they are screen shots taken from the video, [I3 Steel CORDOBESA con extrusor/with extruder](https://www.youtube.com/watch?v=iDtDiW0kTSc).

**Tags:** printer-building, p3steel
> **Comments:**
> **username_1**: It almost looks like a rivit..  
> **username_0**: @StarWind - I can see what you mean, but it's not a rivet, there are circlips on the front and (I assume) the rear also. I'll try to find a better photo - that picture was a screenshot from a YouTube assembly video.  

---

## 3 answers

### Answer by username_2 on 2017-01-17. Score: 2 | Accepted answer

You could look up a [Clevis pin](https://www.pivotpins.com/products/bc-clevis-pins-with-grooves.html) with one groove.  
You could look up a [Clevis pin](http://technifast.co.uk/clevis-pins) with a hole for a split pin.  
Perhaps a [Shoulder screw](https://www.ondrives.com/303-stainless-steel-shoulder-screws#/pageSize=25&orderBy=5&pageNumber=3) with a ground shank and a low profile head.  
Use a plain rod with [Dome caps](http://www.bakfin.com/starlock/metric-capped-roundshaft.html) if you will not need to remove often.  
If available an internal threaded [Standoff](https://www.unicorpinc.com/metric-standoffs.htm) would work.  
A [Slotted spring pin](https://www.ondrives.com/carbon-steel-slotted-spring-pins) may work if the hole dimensions are suitable.

**EDIT:**  
You could also cut the grooves yourself pretty easily. Cut a section of 8mm rod to length and mount it into a drill chuck so it stick out 2-3mm 1/8". Hold a hacksaw at the edge of the chuck and run the drill for a minute with gentle pressure, try hacksaw on other side or reverse direction if nothing is happening.  
A hardened rod will cut better with a Dremel type cut-off disk

[![enter image description here](https://i.sstatic.net/fzlGw.jpg)](https://i.sstatic.net/fzlGw.jpg)


---

### Answer by username_0 on 2017-01-17. Score: 1

I have finally received a reply from my supplier, which backs up StarWind's answer:

> I did not use a rod with grooves for retaining rings.
>
> I used bolts and nuts with a thin head.

Doesn't really answer my question though, as I really rather hanker after the 8 mm smooth rod with the circlip grooves.


---

### Answer by username_1 on 2017-01-05. Score: 1

Oh fascinating. It took me a while to figure out what exactly that is. It is a smooth rod used as the idler for the X belt.

What I would do is get a bearing / wheel. Take a thicker screw, nut and washer. Put the idler / bearing / wheel into the slot, then fit the screw / nut. Should work without any issue!

That said they likely had some sort of special fitting etc. Doesn't matter so long as the belt can move without wearing.

[This Thingiverse](http://www.thingiverse.com/thing:157303) does exactly what I am thinking.

[![bolt example](https://i.sstatic.net/x7BkI.jpg)](https://i.sstatic.net/x7BkI.jpg)

As you have a low profile need due to the interesting design I came across [this](https://www.belmetric.com/index.php?main_page=product_info&products_id=4030&cPath=3_569_718&gclid=CM6Pifm5rtECFVK5wAodMq8HLg&zenid=9o5khnodisqvndhvoejl6b6t40). a TNF8 - Nut Sert - Flanged/Ribbed.
[![enter image description here](https://i.sstatic.net/Z4gAg.jpg)](https://i.sstatic.net/Z4gAg.jpg)

Or you may just need a standard low profile nut. Not like you need it to do more than hold it in..
[![enter image description here](https://i.sstatic.net/szyvM.jpg)](https://i.sstatic.net/szyvM.jpg)

> **Comments:**
> **username_0**: Thanks for the reply. The smooth rod is not the idler, per se, yet it _is_ the axle for a 608zz bearing. I have updated my question, with additional images and a link to an assembly video, that I found on YouTube. I had considered using an M8 Bolt, however, space is rather tight, and the head of the bolt could interfere with both the Z-axis 5 mm smooth rod and the M5 threaded rod (or M8 lead screw). Hence the requirement for the grooved rod, and the circlips, as this requires less clearance.  
> **username_1**: Yeah that's exactly what I thought it was   
> **username_1**: Yeah that is a tight design. Contacting the MFG for the part / the seller is best.. Else you will be Epoxying that thing together...  
> **username_1**: You know they do sell thin nuts. Edited answer for something that may help  
> **username_0**: -The nut sert looks promising. :)  
> **username_0**: I do hanker after that special short rod though. I have contacted my Polish supplier, but as I mentioned, they aren't very communicative. I may need to try to contact the Spanish chaps who designed the idler, if/when I manage to locate them.  

---

