Ground glass

I may have sent this to the list before but, why not again.

 

It is fairly easy to make you own real ground glass. I have done this many times. Little skill is required. Here is how you do it:

 

First obtain some powdered carborundum powder in grit no. 400.

Have a sheet of single strength window glass cut in the size you wish. Better get two sheets in case you break one. Also get a couple of smaller sheet maybe 1/4 the size of the first.

Put a pile of newspapers down on an old worktable.

Put the big sheet of glass down on the newspapers.

Mix up some carborundum powder with a little water. You can mix it right on the glass sheet.

Put the smaller glass plate down on top of the mixture and press down with your fingertips. Move the top plate around in a circular fashion swirling around and around and covering every

inch ofthe surface of the large plate. You will hear a grinding noise. After a while, rinse off both plates and dry the large plate with a paper towel. Now hold it up to the light. You will see frosted areas and places you missed. Repeat the above proceedure and concentrate on the ares you missed. After a while the entire plate will be evenly frosted.

 

By using finer powder say 600 or 800 you can make a finer screen.

 

I have used this method to creat frosted glass screens as large as 3 ft x 4 ft and as small as one inch square. You can "frost" one side of a lens or prism or anything you can grind in this way.

 

This is a little like the way one grings a telescope mirror.

 

Bob Schramm


Check out my web page at: