Repairing body plastic

[Joeywhat]

Just curious if anyone here is versed in repairing body panels. I have a handful of panels that are cracked in some way. Wondering how I can fix these well enough to go over them with some paint (or maybe plasti-dip, not sure yet). I can't really pull the crack apart enough to get epoxy or something in there... I haven't done much plastic repair so I don't know the tricks and such.

 

[Whooshka]

They sell plastic welding kits. Cheaper ones are basically a soldering iron with different type plastic rods (PVC, ABS, etc). You reinforce on the backside of the panel, then make a "channel" on the front side with the welder so that you can then fill, sand and paint.

 

[Oldbikefixr]

I have repaired several over the years. Always with an epoxy suitable for plastics. Clean out the crack....alcohol works well and completely evaporates away....to remove any oily stuff that bonds don't like. Use sandpaper to rough up an area 1/2 inch wider than the crack on the back side of the part. Squeeze in the epoxy, make sure it permeates the crack. You can use a Dremel on the back side to make a channel for epoxy if the crack won't pull apart to accept the glue. You would like for the epoxy to squeeze through to the outside of the part. Wipe it off. Cut a strip of fiberglass cloth the width of the roughed surface on the back side. Use the same epoxy to wet the glass strip and glue it down. Cover with wax paper and work it smooth before the epoxy cures. Pull off the wax paper, scrape the epoxy that squeezed through to the outside. Sand smooth when cured and paint.
When cracks are in a location where this process won't quite work, get it welded. Our BMW shop does a good job on this. Bound to be someone in your area who can.
Whichever you do, the crack must be sealed. They will return as the plastic flexes over time otherwise.

 

[Martin Schneuer]

I used JB Weld to repair about 30% of the fairing with cracks. Fix very strong. You can improve the joints with a fine mesh.
I bought it at

Amazon.com: J-B Weld 50139 Plastic Bonder Body Panel Adhesive and Gap Filler Syringe - Black - 25 ml: Automotive

Buy J-B Weld 50139 Plastic Bonder Body Panel Adhesive and Gap Filler Syringe - Black - 25 ml: Adhesives - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

A picture of the retired bike is the following

 

[Mark]

If you're fixing panels they are made of ABS plastic. I got some pieces of grey ABS plumbing pipe and grey ABC cement and used them to repair a hole in a saddle bag (in the grey area on an ST1100). You could not find the area by looking at the saddle bag when it was closed. You could see it from the inside...

 

[Joeywhat]

Awesome, I'll give these a try.