Pro tip: I see a lot of guys still trying to use old-school body filler over modern adhesives.

Had a '94 Chevy pickup come in last month, quarter panel repair. Previous shop slapped a quarter inch of filler over the factory seam sealer. It cracked in a week. The new panel bonding adhesives need a clean, bare metal surface to work right. You can't just treat them like Bondo. Anyone else run into this and have a good way to explain it to old-timers?

3 comments

3 Comments

marknelson2mo ago

Man, that's so true. Had a guy bring in an '02 Silverado with a bed side someone globbed filler onto. It was like a half inch thick over the factory adhesive. Tried to tell him it wouldn't hold, but he insisted. Sure enough, it spiderwebbed after the first rain. The new stuff just needs that clean bite on bare metal, it's a totally different animal. Trying to explain it feels like talking to a brick wall sometimes.

jessica_miller2mo ago

Yeah, the "clean bite on bare metal" is the whole thing. I grind it all off, hit it with wax and grease remover, then scuff with 80 grit. If there's even a hint of old sealer or primer left, that adhesive isn't gripping. It's not glue, it's a weld in a tube. Saw a roof repair fail because someone didn't strip a thin layer of epoxy. Peeled right off.

victor_carr251mo ago

Used to think it was all the same stuff. Saw a repair fail just like that and it clicked. You can't cheat the prep work with these new adhesives.