From The Toolbox: My Polisher w/Knot Cup Brush
By Chuck Cage
Having seen too many guys with bits of wire sticking out of their bellies, I decided long ago that a) I’d never use a straight wire brush on a power tool, and b) I’d avoid sticking any kind of brush on a 10,000 RPM angle grinder. Anything doing abrasive work at that speed will shed bits, and I’d rather not find those in me.
So here’s my solution: quite a while back I picked up a cheap(-ass) Chicago Electric 7″ polisher/sander from Harbor Freight and installed a knot cup brush on it. It spins at a max of only 3,300 RPM, which works fine for knocking off paint and corrosion but keeps the wire where it should be.
Note: I just checked and the same model is still for sale at HF for $50. If you keep an eye out, though, this item tends to end up in the sale bin pretty regularly. And if you’re worried about reliability: I can’t vouch for it as a polisher/sander, but I’ve used this tool in this capacity on and off for four years now.
7″ Variable Speed Polisher/Sander [Harbor Freight]
June 12th, 2007 at 11:54 am
I’ve had the infamous wire jump into my finger. Anything to keep it from happening again.
June 12th, 2007 at 1:58 pm
My husband just found wire stuck in the back of his boxers. He hasn’t used a wire brush since he moved here. In March. So I assume it’s been working its way through the laundry ever since. (And, his brush wasn’t even attached to a power tool — he was wire brushing radiators before painting. Perhaps too enthusiastically?) That said, this looks great.
June 12th, 2007 at 7:21 pm
What? Use a straight wire brush? Here–shake hands with DANGER! *twang*
June 12th, 2007 at 9:13 pm
I’ve picked a few strands of wire out of the end of my nose after a good Dremel session before. That’s no fun, and it’s also a very good argument for wearing a full-face safety shield (like what dentists sometimes wear when drilling on teeth; I have one but I rarely use it because it fogs up fast unless I’m standing in moving air). Safety glasses don’t protect against that sort of thing
I, too, have found rusted wire fragments in my clothing after the laundry. Oops.
June 13th, 2007 at 2:06 am
I don’t know if the lower rpm will completely save you. I’ve had wires buried in my skin from using a wire brush in my drill. Owwch!
June 13th, 2007 at 4:48 pm
I have a polisher from HF I use for polishing, and it gets the job done, especially since the result of polishing is from technique. You can get the same results with a cheap-ass polisher as an expensive one if you just use the right bonnets, compounds, and technique. Definitely worth the $30 I spent on it. Mine gets damn hot when running, though, and I wonder what the duty cycle really should be. Guess I’ll just run it ’til I burn it up.
July 24th, 2007 at 2:05 am
What diameter knot cup brush do you use? 4″ 6″???
harbour freight has a sale on (for $30)
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=92623
but your model (is $55)
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=90820
Is there a significant diference?