Answers.Body: <p>From accidentally destroying some older wheels (decades on a sunny windowsill can make red parts brittle), I think you're out of luck.</p>
  <p>The ends of the metal axles I've seen have had splines formed into them, then as far as I can see the plastic is moulded over the top. To see what I mean, imagine something like <a href="https://www.bricklink.com/v2/catalog/catalogitem.page?P=32209&amp;name=Technic,%20Axle%20%205.5L%20with%20Stop&amp;category=%5BTechnic,%20Axle%5D#T=S&amp;O=%7B%22iconly%22:0%7D" rel="nofollow noreferrer">32209 Technic Axle 5.5L with Stop</a>, then covering the end with the stop with modelling clay - you won't get the clay off in one piece.</p>
  <p>The good news is that ABS (the plastic used in most Lego parts) has <a href="https://www.kelco.com.au/wp-content/uploads/2009/02/abs-chemical-compatibility-guide.pdf" rel="nofollow noreferrer">good resistance to oxalic acid</a> and you can get rust removers based on oxalic acid (some advice <a href="https://azrust.com/oxalic-acid-for-rust-removal/" rel="nofollow noreferrer">here</a>).  It might turn the steel black; I know phosphoric acid does.  Note that phosphoric acid, citric acid, and acetic acid* aren't good for ABS, ruling out many commercial rust-removers and home-made recipes.  There's always a chance of damage, but less so than trying to get the assembly apart.</p>
  <p>I tried an experiment.  After about an hour and a half in vinegar, the plastic was unaffected, but the rust hadn't reduced, so you may need something stronger.</p>
  <p>But before I put the assembly into the vinegar I noticed one of the wheels was cracked (actually both now I look at the photo!), so I risked prising it off.  After scrubbing some rust off using steel wool you can see the groove in the axle where the plastic is moulded to grip it (red arrow), confirming that it's not coming off without damage.  I was slightly wrong though - this part isn't splined, presumably because it doesn't matter if the wheel slips round the axle.
  <a href="https://i.sstatic.net/ZVO52.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/ZVO52.jpg" alt="Axle with groove" /></a></p>
  <p>If you insist on disassembly, applying enough heat to just the axle will soften the plastic touching it, allowing you to pull it out.  Reassembly would need glue.  But I think (from  memory, bricklink doesn't have a picture of the underside) you couldn't heat the axle without melting the plate.</p>
  <hr />
  <p>* From the source I used, 20% acetic acid is bad, but vinegar (4-8% acetic acid) is good. Whether the soaking time to remove the rust is long enough to cause problems for the plastic would require an experiment.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-09-14T12:15:15.960Z
Answers.Text: What about vinegar? It is much more common than oxalic acid and is also known to be used for rust removal. It also seem to have "A-excellent" rating on the list you've attached.
Answers.UserDisplayName: Alex
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Answers.CreationDate: 2021-09-14T12:23:14.050Z
Answers.Text: @Alex I searched "acetic acid" in that list (vinegar being 4-8% acetic acid) and even at 20% it gets C - "should not be used".  I didn't search vinegar by name.  It might be worth trying it.  If the wheels are important, testing on a damaged/less useful part (perhaps of the same colour) might be a good idea.
Answers.UserDisplayName: Chris H
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Answers.CreationDate: 2021-09-15T12:13:41.463Z
Answers.Text: I was considering the heat solution in case it was using some kind of pressure system, you just confirmed some of my worries. I got the wheels on a similar 2nd hand package you speak about and they are the only pieces of that kind I have so I did not want to risk breaking them. I will try my best to clean them without disassembling and not ruining them!
Answers.UserDisplayName: Jade
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Answers.CreationDate: 2021-09-14T11:15:49.887Z
Answers.LastActivityDate: 2021-09-17T14:56:44.513Z
Answers.LastEditDate: 2021-09-17T14:56:44.513Z
Answers.UserDisplayName: Chris H
Body: <p>I have <a href="https://www.bricklink.com/v2/catalog/catalogitem.page?P=122c01" rel="noreferrer">Plate, Modified 2 x 2 with Wheels Red</a> with metal axles that have developed rust and I need to sanitise them, as I have rust even on the plastic pieces</p>
  <p>This is an example of wheels I need to disassemble:</p>
  <p><a href="https://i.sstatic.net/FZXPQ.png" rel="noreferrer"><img src="https://i.sstatic.net/FZXPQ.png" alt="122c01 Plate Special 2 x 2 with Wheels Red (from rebrickable.com)" /></a></p>
  <p>Before trying more things and avoid breaking them, I would like to know if is it possible to extract the axles with no damage (the axles are inserted by pressure) or are they glued and should try to clean the rust without disassembly</p>
  
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2021-09-13T11:44:46.087Z
Comments.Text: Not an answer, just a comment, as I can't prove a negative: [Bricklink](https://www.bricklink.com/v2/catalog/catalogitem.page?P=122c01&idColor=0#T=C&C=0) treats the entire assembly as one part, indicating that it is not meant to be disassembled. That of course doesn't mean it _can't_ be disassembled though, but could mean that such disassembly would cause damage to the parts.
Comments.UserDisplayName: zovits
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2021-09-13T19:11:46.580Z
Comments.Text: @zovits thanks for your comment, maybe you are right. I assume they are one part because they are meant to be together, not because it cannot be disassembled, or because of the metal axle not being a LEGO part. Maybe I cannot disassemble because of the rust or the material expansion, or they are just glued! That's because I am asking :D I will try something by the weekend if I do not get an answer :(
Comments.UserDisplayName: Jade
Tags: <disassembly><wheel>
Title: How can I extract a metal axle from a plastic wheel without damaging them?
UserDisplayName: Jade
ThreadText: # How can I extract a metal axle from a plastic wheel without damaging them?
  
  (Asked by: username_0 on 2021-09-12)
  
  I have [Plate, Modified 2 x 2 with Wheels Red](https://www.bricklink.com/v2/catalog/catalogitem.page?P=122c01) with metal axles that have developed rust and I need to sanitise them, as I have rust even on the plastic pieces
  
  This is an example of wheels I need to disassemble:
  
  [![122c01 Plate Special 2 x 2 with Wheels Red (from rebrickable.com)](https://i.sstatic.net/FZXPQ.png)](https://i.sstatic.net/FZXPQ.png)
  
  Before trying more things and avoid breaking them, I would like to know if is it possible to extract the axles with no damage (the axles are inserted by pressure) or are they glued and should try to clean the rust without disassembly
  
  **Tags:** disassembly, wheel
  > **Comments:**
  > **username_1**: Not an answer, just a comment, as I can't prove a negative: [Bricklink](https://www.bricklink.com/v2/catalog/catalogitem.page?P=122c01&idColor=0#T=C&C=0) treats the entire assembly as one part, indicating that it is not meant to be disassembled. That of course doesn't mean it _can't_ be disassembled though, but could mean that such disassembly would cause damage to the parts.  
  > **username_0**: @zovits thanks for your comment, maybe you are right. I assume they are one part because they are meant to be together, not because it cannot be disassembled, or because of the metal axle not being a LEGO part. Maybe I cannot disassemble because of the rust or the material expansion, or they are just glued! That's because I am asking :D I will try something by the weekend if I do not get an answer :(  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_2 on 2021-09-14. Score: 6 | Accepted answer
  
  From accidentally destroying some older wheels (decades on a sunny windowsill can make red parts brittle), I think you're out of luck.
  
  The ends of the metal axles I've seen have had splines formed into them, then as far as I can see the plastic is moulded over the top. To see what I mean, imagine something like [32209 Technic Axle 5.5L with Stop](https://www.bricklink.com/v2/catalog/catalogitem.page?P=32209&name=Technic,%20Axle%20%205.5L%20with%20Stop&category=%5BTechnic,%20Axle%5D#T=S&O=%7B%22iconly%22:0%7D), then covering the end with the stop with modelling clay - you won't get the clay off in one piece.
  
  The good news is that ABS (the plastic used in most Lego parts) has [good resistance to oxalic acid](https://www.kelco.com.au/wp-content/uploads/2009/02/abs-chemical-compatibility-guide.pdf) and you can get rust removers based on oxalic acid (some advice [here](https://azrust.com/oxalic-acid-for-rust-removal/)). It might turn the steel black; I know phosphoric acid does. Note that phosphoric acid, citric acid, and acetic acid\* aren't good for ABS, ruling out many commercial rust-removers and home-made recipes. There's always a chance of damage, but less so than trying to get the assembly apart.
  
  I tried an experiment. After about an hour and a half in vinegar, the plastic was unaffected, but the rust hadn't reduced, so you may need something stronger.
  
  But before I put the assembly into the vinegar I noticed one of the wheels was cracked (actually both now I look at the photo!), so I risked prising it off. After scrubbing some rust off using steel wool you can see the groove in the axle where the plastic is moulded to grip it (red arrow), confirming that it's not coming off without damage. I was slightly wrong though - this part isn't splined, presumably because it doesn't matter if the wheel slips round the axle.
  [![Axle with groove](https://i.sstatic.net/ZVO52.jpg)](https://i.sstatic.net/ZVO52.jpg)
  
  If you insist on disassembly, applying enough heat to just the axle will soften the plastic touching it, allowing you to pull it out. Reassembly would need glue. But I think (from memory, bricklink doesn't have a picture of the underside) you couldn't heat the axle without melting the plate.
  
  ---
  
  \* From the source I used, 20% acetic acid is bad, but vinegar (4-8% acetic acid) is good. Whether the soaking time to remove the rust is long enough to cause problems for the plastic would require an experiment.
  
  > **Comments:**
  > **username_3**: What about vinegar? It is much more common than oxalic acid and is also known to be used for rust removal. It also seem to have "A-excellent" rating on the list you've attached.  
  > **username_2**: @Alex I searched "acetic acid" in that list (vinegar being 4-8% acetic acid) and even at 20% it gets C - "should not be used".  I didn't search vinegar by name.  It might be worth trying it.  If the wheels are important, testing on a damaged/less useful part (perhaps of the same colour) might be a good idea.  
  > **username_0**: I was considering the heat solution in case it was using some kind of pressure system, you just confirmed some of my worries. I got the wheels on a similar 2nd hand package you speak about and they are the only pieces of that kind I have so I did not want to risk breaking them. I will try my best to clean them without disassembling and not ruining them!  
  
  ---
  
  