Welcome to the 'bolt, Scruffy. The reason your paint is cracked is the bondo is being pushed up away from the metal by rust. I had the same thing all over my truck, and if you wait long enough entire sections of bondo will fall off on their own.

Bondo and nearly all forms of primer absorb moisture like a sponge; so once the paint is cracked, the process accelerates.


1955 First Series GMC 250 1-Ton Panel
In the Gallery
Mr. Hedgehog - Follow the build
If you can't laugh at yourself, I'll laugh at you.