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Plastic welding is a thing. I doubt they used thermosets so you should be able to melt the pieces back together with a soldering iron or similar (and for some o

Plastic welding is a thing. I doubt they used thermosets so you should be able to melt the pieces back together with a soldering iron or similar (and for some other plastics, CA glue and other solvents will work too.) You can even embed wires or other metal pieces for reinforcement. 3D printing is the "trendy maker" thing these days but don't forget that you can make a replacement out of a suitable material in many other ways, and one that may even outlast the official part. I have in the past repaired plastic parts of appliances by making a replacement out of scrap sheet metal. There's no need for official parts when many people can figure out how to fabricate replacements --- which is one of the reasons why companies are so against right-to-repair. You can do a lot these days with some basic tools (also quite cheap) and YouTube videos.

TeMPOraL 3y ago
> Plastic welding is a thing. Good to know, I'll research it. In the past, I've attempted fixing plastic items with soldering iron and other sources of heat, up to and including open flame from a lighter - in every case, it resulted in burning and/or smoking and stinking plastic, and at no point the two parts became attached again. Not sure what I was doing wrong.
- joecool1029 3y ago
  Epoxy usually works for these situations, it can stink until it sets, don't get it on your hands but it's real cheap. Sub-$2 for the harbor freight tubes. Even better, most of the plastic housings on things (think plasticky old dell desktop housings or lego bricks) are made of ABS. This stuff you can buy plastic weld that dissolves the outside of the pieces you want stuck back together. This stuff works well for that: https://www.amazon.com/Plastruct-Plastic-Weld-applicator-Bottle/dp/B00FDFWJD8 https://www.amazon.com/Plastruct-Plastic-Weld-applicator-Bot...
  - userbinator 3y ago
    That looks like a dichloromethane + MEK mix, but for ABS, acetone works very well and is cheaper and less toxic.
- thinkyfish 3y ago
  Some plastics melt at a certain temperature (thermoplastics like PETG/PLA) and others don't (thermosets like resin/epoxy). Its possible you just attempted to melt the type that just burns when you heat it.
- PeterisP 3y ago
  To clarify, plastic welding generally implies melting the plastic not with heat but with specific solvents. It's kind of "gluing" where there technically there is no glue (i.e. some substance that stays between your two parts) but rather a weld, where the edges of the parts get melted and stuck together as the "glue" (solvent) evaporates.
  - TeMPOraL 3y ago
    > melting the plastic not with heat but with specific solvents Thank you, this is the core insight I was missing!
MostlyStable 3y ago
This is a really good point. It might end up looking janky (I'm bad at the kind of detail level finesse it might take to look good), but slopping a bunch of glue on there would almost certainly hold it in place well enough to work.
Fradow 3y ago
Depending on how it's broken, sometime you'll be able to glue plastic parts together (it was recommended to me to use the gel super-glue, not the regular one). Another interesting material is two part epoxy (like JB Weld). You can even make small parts out of it, for example redo a broken clip on a bigger plastic piece. Due to owning and repairing a 20yo car with lots of brittle plastics, I've had to expand my plastic-repair skillset, and it's way deeper than you'd initially assume.

TeMPOraL 3y ago

> Plastic welding is a thing. Good to know, I'll research it. In the past, I've attempted fixing plastic items with soldering iron and other sources of heat, up to and including open flame from a lighter - in every case, it resulted in burning and/or smoking and stinking plastic, and at no point the two parts became attached again. Not sure what I was doing wrong.

joecool1029 3y ago
Epoxy usually works for these situations, it can stink until it sets, don't get it on your hands but it's real cheap. Sub-$2 for the harbor freight tubes. Even better, most of the plastic housings on things (think plasticky old dell desktop housings or lego bricks) are made of ABS. This stuff you can buy plastic weld that dissolves the outside of the pieces you want stuck back together. This stuff works well for that: https://www.amazon.com/Plastruct-Plastic-Weld-applicator-Bottle/dp/B00FDFWJD8 https://www.amazon.com/Plastruct-Plastic-Weld-applicator-Bot...
- userbinator 3y ago
  That looks like a dichloromethane + MEK mix, but for ABS, acetone works very well and is cheaper and less toxic.
thinkyfish 3y ago
Some plastics melt at a certain temperature (thermoplastics like PETG/PLA) and others don't (thermosets like resin/epoxy). Its possible you just attempted to melt the type that just burns when you heat it.
PeterisP 3y ago
To clarify, plastic welding generally implies melting the plastic not with heat but with specific solvents. It's kind of "gluing" where there technically there is no glue (i.e. some substance that stays between your two parts) but rather a weld, where the edges of the parts get melted and stuck together as the "glue" (solvent) evaporates.
- TeMPOraL 3y ago
  > melting the plastic not with heat but with specific solvents Thank you, this is the core insight I was missing!

MostlyStable 3y ago

This is a really good point. It might end up looking janky (I'm bad at the kind of detail level finesse it might take to look good), but slopping a bunch of glue on there would almost certainly hold it in place well enough to work.

Fradow 3y ago

Depending on how it's broken, sometime you'll be able to glue plastic parts together (it was recommended to me to use the gel super-glue, not the regular one). Another interesting material is two part epoxy (like JB Weld). You can even make small parts out of it, for example redo a broken clip on a bigger plastic piece. Due to owning and repairing a 20yo car with lots of brittle plastics, I've had to expand my plastic-repair skillset, and it's way deeper than you'd initially assume.