Take a brass lap, dress it to half the thinness of the rib, take a 220-grit, medium, hard-bond, aluminum oxide, nonoil-filled stone and slice it to half the thinness of the rib.

Then smooth off the tip of the brass lap, apply a drop of ethyl cyanoacrylate glue (instant nail glue available at any drug store) and glue the slice of stone directly to the lap. Wait about a minute, then apply just enough 220-grit natural diamond compound to impregnate the pores of the stone and start the sweeping action on the EDM – you are now using the ultimate rib polishing tool.

This combination offers the following benefits:
It accelerates controlled EDM stock removal like no other motion or technique.
The 220-grit diamond is not shattering at all because it’s embedded safely in the pores of the stone.

The diamond compound remains aggressive until it is completely worn out and then is easily refreshed by applying just enough compound so as to refill the pores in the stone.
It also may be used as “draw” in a profiler, but side-to-side sweeping is much faster; therefore, draw should only be used to finish and not to rough out.

The fact that the 220-grit diamond particles fall so neatly into the pores of the 220-grit stone creates nothing less than a “super” diamond file, which is glued to a brass lap that is unbreakable and will never wear out.

When the stone slice wears out, simply glue another one back on and you have a brand-new, super diamond file.

One five-gram tube of 220-grit (mesh) natural diamond applied properly is enough to easily polish all of the ribs most shops produce in six months or more.

Gluing a piece of stone onto a brass lap, charging it with natural diamond and using it in a sweeping side-to-side motion is nothing more than taking the best parts of several different techniques. This solution has worked very well over the years and has cut rib polishing time on some jobs by as much as 50 percent or more – without risking rib damage.