PSA: That time a detail shop burnout taught me about paint thickness gauges

I was over at a buddies shop in Phoenix last month helping him with a full respray on a 2010 Mustang. This old guy who used to work at a high end detail shop walks over and says 'you're sanding too deep on that quarter panel.' I blew him off at first but then he showed me the gauge reading and it had already dropped from 140 microns to 90. Now I check depth before I touch anything with sandpaper. Has anyone else had an old timer call them out on something like that?

2 comments

2 Comments

andrew9161mo ago

Is it really that big of a deal to lose 50 microns?

umaprice1mo ago

Oh come on, yeah it kinda is. 50 microns might sound tiny but in machining or 3D printing that's a whole lot of wiggle room. Think about it, a human hair is around 70 microns thick. So losing 50 microns is like shaving off most of a hair's width. If you're trying to fit two parts together that's the difference between a snug fit and something rattling around. In engineering those little bits add up fast and suddenly your project is off by a mile. So yeah, it's a big deal if you care about things actually working right.