I'm at a point with my six inch mirror that I've just about removed all the pits left over from the larger grits ( I'm currently using #240). However, I have a distinct bubble in the center of the mirror while grinding.
I suspect that I should get rid of this bubble before moving on to the next smaller grit. I was going to continue with the present grit using normal 1/3 center over center stroke and alternating the mirror and tool on top until the bubble is gone. Any advice ?
Thanks, Gary Lowell glowell@sgi.com