How do I handle cracked ABS?

So two corners of my ABS space cell pro 4 enclosure cracked (almost completely off, but not quite) and I tried using some plastic weld JB weld on it. It seemed to be sturdy, but every time I tighten it down, it ends up eventually splitting open again.

Does anyone have any advice on how to best tackle this issue?

You could give it a go with abs/pvc pipe glue from a hardware store or Airfix model glue. You don’t need too much as it melts the surfaces together. Got a photo of the problem?

I think that was the idea with the jb weld as well. You can see it starting to crack again right above the bolt

Isn’t jb weld an epoxy? That may remain brittle on the surface if that is the case. The pipe/plastic model glue actually fuses the plastic together.

It’s this one. My understanding is that it would bond the plastic similar to using an acetone treatment.

Not familiar with that but from the description it doesn’t sound like it will melt them together looking at the range of other materials it will stick? You may be able to pick it off and give abs pipe glue a go. If you want to use this one your best bet is to have rubbed the surfaces down well beforehand. Cracks in plastic can be stopped or slowed by drilling a clean hole at the very end of the crack. You could then fill this with the JB weld?

Alright I might try that, I was going to sand the edges down for a better seal, but since the piece wasn’t completely cracked off I didn’t want to break it off. I might just have to do that and hope for the best.

Hey @Jinra - you should be able to resolve the issue with epoxy resin - I’ve used Araldite on my SPACE CELL 4 enclosure too - quite drastically in fact as I’ve removed around about a 60mm section out of it to reduce the size and have glued the 2 pieces back together! Just in the process of finishing it now, and have sprayed the whole thing over in rubber wrap and whilst not perfect it’s a pretty reasonable finish. The trick is to ruff up the edges a little first and then really pool it on the underneath section to give it a little more strength. Also, make sure you get it right in the crack too and just a thin layer on the visible top side as you’ll sand that flat. I tried the weld filler too but it’s just a little bit too brittle. Here’s a couple of quick pics:

It looks like the same stuff you’ve posted:

https://www.blackwoodsxpress.com.au/adhesives-sealants/araldite/aralditer-5-minute-adhesive-24ml-selleys.html?gclid=Cj0KEQjwrsDIBRDX3JCunOrr_YYBEiQAifH1FrxSEhBDrWNb1osUd-AvRTJEbq7bcfXYmG99-3sSglsaAspl8P8HAQ

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Solder iron… Stitch in perpendicular to crack, using a wide chiseled tip. The material flowing out while stitching in, needs to be stuffed back into the slit you created. Do one “weld seam” next to another, approximately every 3-4 mm. Do the front and back side of the crack.

ABS is a thermoplastic and melting it back together is the way forward. Glue doesn’t really work.

Frank

Lol…I’d definitely take @trampa’s advice over mine :smile: I have to say the glue is holding solid but it definitely is a cheap and dirty solution.

welding (sewing it back together doesn’t look pretty in the end. But you can ad some reinforcement plates from ABS material ( e.g. from a ABS plastic box). After finishing the job, you need to sand down the weld seam. If you are missing a piece of ABS, you can ad that in, using ABS sheet material. I use plastic boxes used for electronics. They are often made from ABS.

Frank

I had issues with my Spacecell enclosure cracking. Once I repaired one area, another would start cracking. I drilled some additional holes so that the stress would be distributed better. Helped some, but I ended up replacing the whole thing for a CF enclosure.

What about some sugru on the corners? It sticks very well once cured, and it’s a bit flexible, so it doesn’t crack

drill at the end of the crack - will stop it cracking any further

@Jinra I think @trampa is right about this but be aware that hitting ABS with a soldering iron is going have a really caustic odor and none of the smoke or vapor should be inhaled. Suggest doing this below an industrial hood or outside with a respirator.

@DanSkates what product did you use to do this? it looks cool!

In that case never print APS on a 3D printer. Outside is best…

Tried acetone? Like in nailpolish remover Melts abs and then evaporates away leaving all pieces pressed together fused. I always use it with my prints. You can even dissolve some extra black abs In acetone and pour to fill gaps. It will also be sandable. Never tried with this enclosures though

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I used this:

I had a play around with the crazy teal one too on my trucks but decided it was a little too wild! It peels off, but does take a bit of work! You literally have to get something sharp and scratch it to get it started so I’m hoping it will be fairly hard wearing? :muscle:

Apologies @Jinra for thread jacking! :blush:

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thanks for the suggestion guys. I’m going to wait until the piece fully comes off, then I’ll rough up the sides and try an acetone treatment along with more epoxy

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