Mirror Polishing Machine Question

I was wondering what kind of motions one uses with a mirror polishing machine and I came upon the following webpage:

lerch.no-ip.com/atm/Projects/Polisher/page_01.htm

There are actually a few MPEG files that show the machine in action. (at the bottom of the page)

My question is this: How does the movement of the tool change as you move through your grits? And into final polishing?

Thanks for any insights...

Kwang

Kwang, The tool in this setup is generally set to a stationary position based on the focal length desired. Moving the tool further out increases the focal length and moving it in decreases the lenght.

Once you are close to the desired focal lenght, you do not move the tool in or out as you will start to develope another sphere either outside or inside the previous one.

In polishing to a sphere, you also keep the lap in the same position as the grinding lap.

One may introduce a bit of ecentric motion to avoid zoning once polishing...

It is only when you began to figure that the arm strokes across the mirror, but at this point the mirror rotation is SLOWED to almost a crawl...like 3-6rpm versas 40-60 during grinding and polishing...

The following is a good site that supports the MOM "Mirror Matic"

http://groups.yahoo.com/group/Mirror-O-Matic/

Very useful and active site...

Hope this helped,

Regards Preston

ps...There are other ways to use the machine, but what I discribed is likely the most popular...and Carl Zambuto also uses this basic method.