Update: Watched a guy try to feather edge with a grinder on a quarter panel

He was working on a 2018 Civic in the bay next to mine and went straight at it with a 40-grit disc, no blocking at all. I had to stop him before he went through the metal and explained you need to use a softer block to spread the pressure. How many of you still see people skipping the blocking step on a big repair?

2 comments

2 Comments

the_ruby7h ago

That's a classic move, but the real problem is using the grinder for the whole job. You need a DA sander with 80-grit to get it close, THEN switch to a block with 180. The grinder is just for taking down the high spot of the filler, not shaping it.

tara7006h ago

Oh man, that's painful... @the_ruby is right about the DA sander, but even before that, how do you get the filler profile right without a block? I've seen guys just push the spreader with their hands and end up with a huge hump.