How Can I Repair Broken Plastic?

[Smit-Dog]

A tree jumped out in front of my bike, and ended up breaking off one of the plastic tabs that secures the plastic headlight assembly to the fork.

I've never used JB Weld, but am wondering if it would work for welding broken plastic back together? This is not a high-stress part, but I don't think that Crazy Glue would hold up. Looks like the JB Weld company makes a bunch of different welding compounds for different uses. Which one works best (if any) for plastic?

Thanks!

FWIW, here's a diagram of the broken piece:

 

[nitro5185]

JB Weld should work fine. You might even want to try a epoxy.

 

[Zerotact]

I tried epoxy and it does not work the plastic is too flexible...
You may try to local someone with a plastic welder... they do exist...
A lot of people use headlights with mounting straps to alllow more flex in situations like this

 

[RM_guy]

I had a tab that broke off a rad shroud once and used "Shoo Goo". It sticks to polypropylene (dirtbike body plastic material) pretty good and stays flexible so the plastic can still flex. You can also glue in some additional pieces to stiffen the joint too. And you can also drill some holes in the broken and the main piece and lash it on with zip ties before you glue it.

 

[Danman]

Permitex five minute general epoxy. They stuff is like iron from what I've seen. Kind of like JB weld, you squeeze it out and mix it up. I would not use it on metal though, but anything plastic it should do the trick.

 

[Studboy]

Usually epoxy works pretty well if you rough up the surface well first.
Most quick epoxys are still somewhat flexable once dry.
JB weld is too brittle to use, it is really stiff once dry.

 

[OKKX'er]

There is a glue similar to "Shoe Goo" called "Goop". Only thing I could find that would stick to polypropylene with strength and flex. Comes in several varieties at Lowes, ect.

 

[hrc125rider]

drill to wholes and criss cross zipties

 

[Smit-Dog]

Thanks for the tips guys! I'll look for some of that Permitex, Shoe Goo, or Goop. Just looking for a "clean" repair without spending $85 for new plastic. Trying to stay away from the the zip-tie / duct tape look.

 

[RM_guy]

Shoe Goo comes on many "flavors" and they are all the same stuff. It's your best bet for a lasting repair IMO

 

[MrLuckey]

I broke the mounting tabs multiple times. Basic epoxy worked great for me. Rough up the surface, use a bit of play dough or similar to build a dam/well around the bottom of the tab to keep the epoxy in place while it dries.

 

[hoosierf]

I use a small piece of aluminum flashing and a few rivets to fix areas like what you are describing.

 

[Smit-Dog]

Tried the Goop product. Prepped the surfaces well. Seemed to be strong yet flexible like plastic after it cured. First trail ride this past weekend, busted headlight mounting tab off again after a head-on with a tree. Probably would have broke anyway, as this impact also bent one of the metal mounting brackets.

Looks like it's time for the well-beaten look of the zip-tie repair.

 

[RM_guy]

Man, you have to stay away from those trees ! ;)