I was sanding on some fenders and with the bondo and primer it is kind of hard to locate the dents. So I was wondering if you could spray a cheap gloss black spray paint on the fenders to find them, and then sand it all off to fix it?
Its called a guide coat, I usually dust on any type of black spray bomb on light colored primer. Block sand, and you will see your low spots.
That's how I do it, put a dry rag between your hand and the panel and rub, you will feel every ripple.
yeah, the SEM stuff is good. If you go lacquer paint try a flat black. It will clog a lot less than gloss black and keep the can away so you get evenly distributed drops.
The guide coat advice is spot on. I find when trying to feel the surface my palm works much better than my fingers, so I raise my fingers up and just use my palm, works for me.
Doesnt even have to be black, anything that contrasts with your base. Worked in a bodyshop with one of the techs who was always huffing fumes (best reasoning for it i can think of) He made all sorts of colors of primer and guide coated them with others... I'll never forget when the 16 year old girls parents brought her in to see her crunched car, was blue originally, he had the front clip in some slime green with pink cross hatched guide coat. She started bawling when her parents said it was going to stay that way....