Grinding and Polishing Granite

A variable speed grinder and a full assortment of grits, and you're in business. April 20, 2011

I was asked to do some mods that include taking down a pony wall. This will expose the edge of some previously installed granite. This edge will not need a shape, but I will need to polish it. Not something I've ever done. I am assuming I just need the right abrasive disk and an air grinder. Any advice? The edge needing polish is about 3' long and 1.25" thick.

Forum Responses
(Laminate and Solid Surface Forum)
From contributor L:
Diamond grinding discs starting at about 200 and going up to about 1000-2000 grit.

From contributor D:
3, 4 and 5" (4" being the norm) diamond resin polishing discs are available from 50g to 3000g, then black or white buff, which equates to 5000-8500 grit depending on the maker. These have to be used on a variable speed tool (grinder). If you do not use on VS, you will glaze over the diamond. This includes any diamond tool. You may want these in a dry use diamond disc, as using wet may not be an option.

From the original questioner:
Just to follow up, I got everything I needed to go from a rough cut to full bullnose. Have done the original job and a few other small projects. Very simple to do. Dave at Fedsaw was a great help.

From contributor K:
Simple granite work is a cake walk, but be prepared for a lot of dust. Think about a plastic tent to contain the potential disaster. One other option is epoxy, if it's not in too obvious a location. You can buy the epoxy by the quart at granite places. You'd want knife grade, since it's for vertical surfaces. It it's rough, start with the 50. Then work your way up (e.g., 100, 200, 400, 800, 1500, 3000). It'll go quick, so don't jump grits.