Hi all,
So trying to stay busy during the great covid restriction I’ve been staying busy with the plane. First I repainted my interior plastic, now I’ve decided sense it’s already out to try installing some soundproofing. The original Cessna fiberglass stuff is either missing or shot so I’m going with closed cell foam. From other posts I’ve read everyone seems to agree you should apply zinc then apply foam, but what I couldn’t find was a definitive answer on how to get rid of that gooey black crap on the inside of my fuselage skins in the cabin. If anyway has a product and/or procedure I’d love to hear it.
Thanks.
PS, I’ve read post saying leave the crap and posts saying it’s got to go, for corrosion issues, any thoughts on that would be great as well. If I don’t need to I’d rather not....

Paint stripper and endless hours of misery... not sure I’d do it again.

Ugh, yeah, might just put the foam over it like the fiberglass was

Ugh, yeah, might just put the foam over it like the fiberglass was

Yep. Paint stripper and a squeegee taking care with seams is the best I found too.
Then clean up with a few gallons of MEK and a billion microfiber towels.

I don't know if there is any real benefit if you're going to cover it up with foam anyway.

Another idea is to spray more on and paint over for a textured look.

I used a product called Goo Gone. It worked fairly well and isn't as toxic as some of the paint strippers.

Peerco Adhesive Remover - relatively non-toxic and worked well for the task. Ironically, it worked wonders on breaking down the black goop but not so great on the yellowish adhesive. 60 year old adhesive seems to harden into an amber-like substance. Very tough.

I just bought a gallon of Peerco for my 205. It didn't touch the amber adhesive or the door seal adhesive. It did, however, slowly dissolve the black tar. I tried three coats of 10 minutes each on one panel (perhaps a square foot) and squeegeed it off, still don't have it all removed, and used half a roll of paper towels. I can say with certainty that will take too long to do the entire interior, and I'm not taking a bath in MEK to make it happen.

I'm hoping to find a commercial dry ice blaster and try it out.

My key to making Peerco work was to make scrapers out of old airplane windows. It did take some work, but I didn't think it was that bad. Another thing to try is lacquer thinner. Less toxic than MEK, and it worked pretty well on the yellow adhesive and the black stuff.

Toluene - lots and lots of toluene...

Spent a week brushing on Toluene, and then scraping the softened black gunk off the interior of my 172. I also used some PTI Surestrip, it worked really well because it was thick and didn't drip / run off.

Filmed it all for the YouTubes; because that's what you do these days: https://youtu.be/hWfSRnNOvL4