Vent: New sealer bubbled up on a Benz hood yesterday

Last Thursday I painted a Mercedes hood at my shop in Phoenix. Used a new sealer I bought from a supply house I never tried before. Looked perfect in the booth but the next morning it was covered in tiny bubbles. Had to strip it all off and start over which cost me like 8 hours of labor. The supplier said they changed the formula without telling anyone. Has anyone else run into sealer adhesion problems with certain brands lately?

4 comments

4 Comments

vera19514d ago

I think @roberts.leo has a point but Phoenix dry heat can mess with flash times too.

roberts.leo1mo ago

Gotta push back a little on this one. Bubbling on a fresh sealer almost always comes from surface prep or the undercoat not being fully cured, not just a formula change. Ive used a bunch of different sealers over the years and if the substrate has any moisture or leftover solvent trapped underneath, even the best stuff will bubble up overnight. Phoenix humidity is low but that dry heat can mess with flash times too, maybe the sealer skinned over too fast and trapped solvents. Suppliers do change formulas sometimes but usually they put a tech bulletin out about it, sounds like your shop might have just got a bad batch or the gun settings need adjusted.

cooper.drew1mo ago

Man, I've been there too. @hollywhite is right about the dry heat speeding things up, but I've seen that actually cause problems when the sealer skins over before the solvent can fully escape, especially if you're laying it on heavy. Try thinning it just a hair and backing off your fluid pressure, that usually sorts out the bubbles for me.

hollywhite1mo ago

Actually, the dry heat in Phoenix speeds up flash times, not slows them, so that would help solvents escape faster.