another diy groundglass question

[LotusEsp]

Is there a reason why you couldnt use paper rather than grit to work a groundglass?

i.e. something like wet & dry / Aluminum Oxide sheets

[Peter De Smidt]

Try it and report back.

[LotusEsp]

a reasonable suggestion :)

sourcing the grit/compound seems a little tricky here, so was just considering alternatives

[Harold_4074]

There is a big difference in the texture from "free abrasive" as compared to "fixed"; the former rolls and makes pits, whereas the latter slides and makes scratches. I think that you could probably make a useable groundglass using abrasive paper, but if you get scratches from large particles it will take forever to hide them.

As a kid, I wanted to try "lapping" because I had read about it in a book. The only abrasive that I could find was automotive valve grinding compound, which was a bit coarse for optical purposes. But I found that I could burn sandpaper to ash, wash the residue, and recover some pretty fine abrasive.

I haven't kept up with all of the voluminous posts on making groundglasses, so in case it hasn't been mentioned: consider using a second piece of glass to work the abrasive. Anything that can "embed" abrasive particles can lead to scratches just as sandpaper will. Use lots of lubricant, for the same reason--sticking abrasive will act like sandpaper as well.

Good luck!

Harold

[Harold_4074]

There is a big difference in the texture from "free abrasive" as compared to "fixed"; the former rolls and makes pits, whereas the latter slides and makes scratches. I think that you could probably make a useable groundglass using abrasive paper, but if you get scratches from large particles it may take forever to hide them.

As a kid, I wanted to try "lapping" because I had read about it in a book. The only abrasive that I could find was automotive valve grinding compound, which was a bit coarse for optical purposes. But I found that I could burn sandpaper to ash, wash the residue, and recover some pretty fine abrasive.

I haven't kept up with the many posts on making groundglasses, so in case it hasn't been mentioned: consider using a second piece of glass to work the abrasive. Anything that can "embed" abrasive particles can lead to scratches just as sandpaper will. Use lots of lubricant, for the same reason--sticking abrasive will also act like sandpaper.

Good luck!

Harold