Coarse Sharpie Test

Step 1: Coarse Sharpie Test

The Coarse Sharpie test is used on new tile tools to tell when the tool has the same shape as the mirror. Once you have made the tool and it is very dry you mark each of the tiles with an X, as shown. You then proceed grinding with #120 and as the tiles come in contact with the glass the X's will be ground away. If your tiles have glaze on them you may also watch the glaze disappear.

Step 2: Coarse Sharpie Test

Here is the tool after #120. I kept grinding until the very rough surface from #80 was removed. The dark areas are where I have ground through the glaze into the tile. Notice that all the X's are gone, this indicates that the Coarse Sharpie Test is complete. I also looked at the glaze and much of it was being scratched by the grit at this point.

Step 3: Coarse Sharpie Test

Ok the Coarse Sharpie test is really done, but here is the tool after #220. Notice the whole tool is getting gray. The darker tiles are in better contact. Now is a good time to try the The Sharpie Test and see where on the Mirror contact is being made.