After my last tire failure saga, it beat up my door trim plastic pretty bad. Looked like this.
I could not locate a new door trim piece. So I went the “Let’s try and repair it” route. I remember “Frank” doing a great write up on how to repair ABS plastic and found it. See here:
Following Frank’s process I was able to repair my door trim. I am not going to repeat all what Frank did, read his write up for the How Too on the basics of the process. I will expand on it applying it to door trim in place of a black tank. The fenders and the door trim parts are made from ABS plastic so the same process applies.
This is where I started. The right end was broke off and there were several cracks and some missing plastic too.
To stop the cracks from growing, a repair process is to drill a small hole at the end of the crack to help stop it from spreading. This is nick named “Stop Drill” in industry.
Using a round ball cutter in a Dremel I routed out from both sides the cracks and where I had to join the broken end piece back on as ABS welding prep. This allows the weld patch to flow into full thickness of the part.
Next was to create an ABS welding liquid rich in ABS plastic. Start with black ABS cement and then add sawdust size chips of ABS to the cement to create a pancake batter consistency. Need a glass jar with sealing lid. I picked blackberry jam size and it worked well.
First is to make the sawdust sized ABS chips. I bought a 1 ˝” ABS coupling from the lumber yard as the ABS material to grind up. I did not have the exact same cutter as Frank did, but I used a rotary rasp that did the job in a die grinder. You need an interrupted cut cutter. I tried several others and they made more long shavings rather than dust. See here:
Next was to mix up the ABS rich welding fluid. Here is your weld kit. The solder rosin brush or acid brush is your weld applicator.
Now to mix up the ABS rich welding fluid. You use the glass jar as the mixing and storage container. Pour in some ABS cement (must be the black kind as it has ABS plastic in it) and then keep adding ABS chips and stirring with a stick. The chips will start dissolving into the fluid. Keep adding until you get a medium thick consistency like pancake batter. The first day you might get some small lumps and that was OK for me I could work around them. The next day everything was dissolved and no lumps.
Then put the lid on tight to keep the MEK in the ABS cement from evaporating out. MEK is the solvent in the cement that will melt the plastic together. Put this aside for a while.
Now to clean up all the parts. I used Naphtha first to clean all the dirt and grime off the parts. Then when all parts have been test fit and routed/prepped ready to solvent weld, you use Acetone to do a final clean. This will start to soften up the plastic some too.
Then use the acid brush to apply the weld solvent mix. You try to do thin coats. This will take 3 coats and 3 days to complete. After each coat it takes overnight to cure before the next coat. On extra big areas to fill you may need a few more coats.
Here is coat 1. This is a cured 1st pass. You have to support and prop up the parts to be the exact position you want them to cure in. Suggest figuring this out "before" you start welding the 1st time. After the 1st pass is cured, the parts are rigid thereafter. Do not worry about sunken thin areas or holes. You will fill them as the passes keep going.
Since I had a large hole between the 2 parts I decided to reinforce this area behind the part. I cut a piece of left over broken up ABS plastic from the fender and fit it over the large hole on the back side. Then weld it in place.
I had to grind out a little 1st pass weld bumps to have the patch lay flat.
The test fit the patch
And here is the 2nd pass weld on the back side. The front side is just more buildup of the 1st pass.
Also to note, on the 2 day I had to add a little ABS cement to the glass jar mix to thin it out. You really need to put the cover on the jar whenever you are not taking material out as the MEK evaporates fast. This 2nd day mix was even better than the 1st day. It was totally smooth, all bumps of chips dissolved into a rich liquid ABS weld material.
Next was the last 3rd coat. It filled the large pocket on the front well and the joint was strong. I would say stronger and more rigid then original. This 3rd day cure process is amazing how you can “glue” all this back together.
Then to paint the trim. Since I had a bunch of oil based primer and black paint stuck on this ABS plastic that was not coming off, I figured I did not need to use plastic paint as I cannot get the oil based enamel off if I wanted too… So I used Rust-o-leum oil based white. It took 2 coats (spray can) but covered well and is adhered well too.
Here is the repaired trim on the camper. I used stainless screws with small flat washers to spread the pressure out some at the screws. The can of spray paint was the most expense part of this repair. The whole repair parts was under $18.00 and I have even left over to do about 10 more repairs, maybe even more. I did use the acetone to clean out the acid brush which worked great. I did all 3 coats with the same brush and still have it.
A super thanks to Frank for his post on “How To” do this ABS repair.
Hope this helps someone in the future.