thread: Mending ABS plastics

  1. #1

    Feb 2012
    Bratislava
    19

    Mending ABS plastics

    I have cracked one of the important tabs on my AW11 dash cover while dismantling it the other day, so I had to figure out how to fix it. Google came up with good hints, that ABS dissolves in acetone. Which is good because that way, you can melt it and glue together. The thing is, that if you melt the crack surface too much, you'll distort the original shape. So the ideal solution is to make your own molten ABS glue. You can either melt some old interior OR you can use LEGO bricks! Right, LEGO is made of ABS, so i reached out into my Technic box and pulled out a nice small black brick which I thought no one will ever miss (note: some bricks and pins don't melt at all, they just fall apart in acetone).

    Unfortunately, I haven't taken any pics of my masterpiece but the dash cover holds as hell! I have, however, been melting another brick in order to fix and reinforce a cracked heater control from my Celica.

    After the "sacrifice" material started to get gooey, I have picked some of it with a toothpick and started filling the empty area to reinforce it. Looks a bit rough at this point.


    Then, I have grabbed an ear tampon, dipped it in acetone and smoothened the surroundings with it. It remelts some or the edgy bits and fuses everything together. Absolutely unnecessary if you are not into aesthetics :D



    The dash repair wasn't this clean because I was adding layers of ABS plastics all around the crack line to reinforce the tab as much as i could, even gluing the holed metal strip onto the tab.
    With a bit of practice, many cracked parts can be fixed. No need to search egay and breakers for bits

  2. #2
    Grenade's Avatar
    Dec 2012
    Cleveland Ohio USA
    2,027
    You are fantastic. That is a good tip. Melt ABS with Acetone. Perfect!

    The ABS glue used in plumbing applications is also something that should be looked at. I personally never use ABS because it's a low quality plumbing job, I use PVC. But- There's lots of ABS out there and if Acetone works, Hooray! Great find.

  3. #3

    Oct 2010
    Essex
    70
    Funnily enough, I've just done this to repair a door cup and a engine cover release cup which had cracked. I then got brave and decided to have a go at my motorbike front mudguard which had got a piece missing, worked a treat! I sacrificed old broken bits of mr2 trim for mine. Loving the idea of smoothing it back with acetone though!

  4. #4
    headcase's Avatar
    Sep 2010
    east sussex
    589
    acetone vapour smoothes as well that is what i use when printed something to smooth the surface . :)

  5. #5

    Jun 2007
    390
    You are fantastic. That is a good tip. Melt ABS with Acetone. Perfect!

    The ABS glue used in plumbing applications is also something that should be looked at. I personally never use ABS because it's a low quality plumbing job, I use PVC. But- There's lots of ABS out there and if Acetone works, Hooray! Great find.
    you're absolutely bang on about the solvent cement used in plumbing, I repaired a ton of motorbike fairings that had bad cracks, because these parts were visible I patched the crack from behind using of all things flattened abs plastic pipe then used a flexible filler on the exposed surface, sanded and painted

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