Ground Glass ?????

[twocik23]

I just grinded the uv glass and was not impressed!!!!! Does anyone have a special technique ???

This is the tutorial that I used.
http://ideaspora.net/oldskool/alain35-2.html

All I got was a few gashes and scratches. I can't get rid of the gashes.

[Justin]

I figured that method wouldn't come out as perfect as the tuturiol said, Im going to buy mine off that site that I posted.

[twocik23]

I think the glass (on the site) is a few hairs too big! Maybe try to shave it.

I think thats the one for me too.

[bikefilms]

It takes hours to grind the glass with fine grit. Of you aren't into DIY, you're better off buying the gg.

-a

[twocik23]

I tried for about 2hours and it has these deep scratches beneath the surface that will not go away. Everthing else is correct (the frost), but those damn gashes!!!! I'm about to buy a damn suction cup n a makita drill see if that works!!!!!!!!!

[rpster88]

Thor Labs!
only $14 for a 2" diameter 600 grit peice.
http://www.thorlabs.com

[ICED OUT!]

If you start with a shitty piece of glass that is already scratched, grinding it will do you any good. You have to start with a nice new 55mm UV filter and grind one side of it for like two hours (over several days a little at a time) all a while you need to make sure that you do not scratch either side of the UV glass that you are finely grinding.

[bklyndv]

Too late to the party, but...

I wrote that tutorial, and if you do it properly, you shouldn't grind for much more than 20 minutes. The key's are: use the large grinding glass over the filter, not the other way around -- it creates a more evenly dispersed pressure; and make sure the aluminum oxide is soaked with water prior to grinding -- dry "clumps" of alum-ox will result in scratches.

And yes, once the scratches are there, you're better off just scrapping that glass and starting over.

All that said, from the looks of your test footage posted today, you've figured it out and things are looking good for you. Congrats.

[bklyndv]

p.s. one thing anyone reading who intends to do this themselves may consider is placing a single layer of tape over the back of the glass you intend on grinding so as to protect the surface while grinding the other face.