Man, I wish I had known this two years ago. I was doing the same thing you were, wire wheel in one hand and a vinegar bucket stinking up my shop, and it took forever plus the wheel kept loading up with gunk. I grabbed a cheap 1x30 belt sander off a yard sale table and started hitting my stock with a 120 belt before it ever sees the fire, and it cut my prep time way down. The key for me was going slow so I don't burn the steel or dish out the belt, light passes and let the grit do the work. Now my forge stays cleaner too since there's way less scale flaking off and floating around. Dale figured out something good and I'm glad you passed it along.

A wire brush bending fins flat is kinda the whole point if they're already crushed into a solid wall, since a fin comb won't do a thing once the metal is folded over itself. Most of the coils I see are so packed with matted lint and dirt that brushing is just step one before you can even find the fins to comb them. The tool isn't magic, it's the combo of knowing when to scrape and when to straighten that keeps your amp draw down.