I use EXTREMELY light pressure. You can actually get a “mirror shine” on steel with 60 grit belts. I kinda think that it’s a waste to use a higher grit at first. Basically, I hog off a bunch of material with the 60’s, then use very light pressure, which is honestly the only way that I can manage to get things flat, and square everything up. Super light pressure causes shallow scratches. I’m 99.99% sure that I’m doing that all wrong lol. Honestly, I use such light pressure that sometimes I go 60, 120, 220, 320, then buff. The attached picture is of a piece of Koa fresh off the 60’s. It’s
just the way I have always done it. Never really thought about it, because it was just a natural byproduct of going slow and using light pressure.