flap disc

I usally use a knotted wire cup wheel for this application. The flap discs are great for blending welds and deburring edges, but don't try to take off any paint, powder coating, or mill scale with them. As you discovered, they load up pretty quickly.

When getting the wire wheel for your 4 1/2" grinder, you may want to go with a 2 1/2" or 3" wheel. Anything larger requires a lot of torque for the grinder, and you may burn up the motor. Also, be sure to use safety glasses and a face shield when using those wheels. Those little wire projectiles like to go everywhere.

Good luck

I buy a lot of 40 grit discs, a few 60's and fewer still 80's and 120's. Pferd and Klingspor are the best. Klingspor makes a double sided one that only costs about 20% more than a single sided disc.

A leather apron isn't a bad idea either. Like the man said those wires like to go everywhere! Steve

I've been using flap discs in my 4 1/2" grinder for about a year now, and have used them for just about any application. I use the 40 grit for maximum material removal, mill scale included 60 or 80 grit for aluminum or medium material ( steel ) removal. The 80 grit works fine for removing paint or surface rust. The 40 and 60 grit work well for hard pan rust or scale.

Just my .02

Thanks, jw

discovered,

Are you using the knotted wire type or crimped? Knotted lasts way longer.

Steve Smith

bitternut wrote:

"bitternut" quoth:

If you want to remove mill scale from m/s without cutting the metal, I suggest 3M Clean&Strip(tm) wheels. Walther makes a similar product.

Similar to a very coarse Scotchbrite material. For an end grinder, not a side (angle) grinder because you use the edge of the wheel. They won't leave circular grinder marks or swales in the surface. I use the 6" coarse ones on a 1/2" endgrinder spindle. The smaller ones (4"? 3-1/2"?) that come with riveted-on spidle are less effective unless you have an air die grinder 'cause they have to go fast to work well.

They *do* wear away faster than you might like, especially if you hit edges or corners from the wrong direction.

I like flap discs in an angle grinder, too, but I find it's easy to cut swales in the metal, not acceptable for the ornamental stuff I do.

Best I've found are the blue Zirconia ProCut from CSM

Yoiu can use any old junk in 40 grit, but the ProCut disks don't clog in 120 grit. They also make them in 7", which makes my 9" grinder far more contollable, especially with the lightweight plastic backer.

I use wire brushes for surface finishing, but not for edge work.

I have pulled them out of my shirt, and skin. They really fly. But I do love my cup knot wire brushes. Just have to use long sleeves when using them, and then the khaki Wrangler western welding shirts don't stop all the little darts.

Steve

And the wires don't fly off as bad.

Steve