Showerthought: That old guy at the parts counter was right about filler shrinking

I heard a guy in his 70s telling a new tech that bondo shrinks more than they think, and I laughed it off until I wet-sanded a repair I did 3 months ago and saw the ghost of a ding coming back through. Anyone else have a old-timer tip that turned out to be dead on after you ignored it for a while?

2 comments

2 Comments

thomasshah1mo ago

Old timer at the shop told me to always let filler sit for at least 20 minutes after mixing before applying it, lets the chemistry settle or something. Blew it off for years until I started noticing pinholes and tiny bubbles in my work that showed up after painting. Finally tried it his way and the stuff laid down flat as glass. Kicked myself for being stubborn about it.

daniel_walker1mo ago

Lets the chemistry settle" - that's the part that got me thinking. I wonder if there's something to heating the filler can slightly before mixing too, like the old paint mixing trick.