I originally had a thread called looking for source of ABS flat stock. I found the material I needed and have completed the repairs on the hole punched in an ABS plastic panel on my Coleman Cheyenne. My source for the ABS was : http://www.smallparts.com/
Here is what I did. I took some of the ABS flat stock and drilled it with a 1 inch paddle bit to get shavings. I took about 1/2 cup of shavings and covered with MEK solvent in a sealed jar. Shook the jar occasionally and the shaving melted into a goo the consistency of honey (took about a day). Add more MEK if too thick, add more shavings if too thin.
First picture is the front storage box on my PUP
This picture shows the front storage box on my PUP. I was getting water in the box and traced it to the 2 reflectors on the right. I could see a crack in the ABS panel above and below the reflectors. Someone had used silicon caulk to patch the cracks but the silicon was separating from the ABS material.
I removed the 2 reflectors and found about a 2 inch hole in the ABS. Apparently the previous owner had used the reflectors to cover the hole.
Cleaned the area well with the MEK solvent on a rag. The MEK also does a good job removing the silicon caulk from the previous repair attempt.This also softens the ABS and helps it bond to the new material. I cut a piece of the flat ABS stock about 4 inches square. I used 1/8 inch stock and this was probably overkill as the storage box is only 1/16 inch thick. Applied the MEK/ABS goo to the patch and applied over the hole. Held in place for about 2 minutes and the goo was set up enough to hold in place. As you can see, although I bought white ABS the flat stock has a definite yellowish tinge. I plan on painting to match. Picture shows patch in place.
Waited about 2 hours and used more of the goo to fill in around the patch and fill the cracks above and below the patch. I found out with the goo the consistency of honey it flows very well and is almost self leveling. I used a 1 inch disposable foam brush as an applicator. Do not over work the material because it sets up rapidly and will starts to clump up as it sets. If you get some uneven spots, wipe with a rag dipped in MEK and it will take down the rough spots. Don't try to reuse the brush as the MEK dissolves the foam also. Picture shows the patch completed.
Waited a day for the MEK solvent to totally dissipate. Painted the patch with a Krylon Fusion (made to stick to plastics) spray can. White (Satin finish) seemed the best match for my existing color and gloss. Also protects the ABS stock and patch material from UV damage. Picture shows finished paint job.
Last picture shows the reflectors reapplied. I am happy with the way it turned out and it was very easy to do. If you are going to try patching with the MEK/ABS goo, make sure you actually have ABS in you patching goo. All white plastic is not ABS. The MEK will melt most plastics, but the goo will not bond to ABS if you use some other plastic. A good source of ABS for goo is white LEGOs (you know the plastic toy building blocks). Hope this is helpful.