Glass grinding?

[Car3o]

I've heard of people grinding down their beatie's, maybe not beatie's, but other types of focusing screens to fit their needs. What do they use to grind them to a certain size?

-Rh

[Wayne Kinney]

Hi,
Most commen way and is what I used is using aluminium oxide abrassive powder with a few drops of water, and grind agains another peice of glass.

Different grit sizes of the AO will give larger or smaller grain, and will effect lightloss and diffussion/bokeh.

[Alex.Flory]

Hi wayne, I think he meant grinding the size of the screen down.
Car3o, Am I right to say you want to resize a medium format screen to a smaller size?

[Wayne Kinney]

Ah yes, reading it again I think you are right, sorry :)

[Car3o]

yeah, i want to make the glass smaller in size. not necessarily a medium format, but that's the idea. I have a smaller frame size and can't fit much of anything in the holder. what do you suggest doing?

[Inexistence]

cheap glass cutter maybe? It's a pain tho'

[twocik23]

You could sand blast it, look in the phone book for a local glass dealer. I've tried a few pieces and came out very nice.

[Alex0607]

I think a few people are abit confused with your question.
If you want to resize a beattie screen, I would advice against it as the screen is so delicate and easily scratched. and when grinding down the edges, you tend to get specks of the ground particles sticking to the screen due to static and spoil the screen. Not sure how else you can do it safely.

I think Quyen managed to cut a big size screen for his Letus flip enhanced. The screen is an oversized one. Not sure how he did it.

BTW, Beattie screen isn't made out of glass so grinding the edges down shouldn't be too difficult I suspect.

[Car3o]

I never said I was using a beattie, I know better by just people saying how the sneezed on it and it scratched. I would never drop over 175 on a screen.

The question is this. If I have a screen that is 40mmx40mm and I want to grind it down to 20mmx20mm(just example here) how would you go about scaling it down.

I hope that makes more sense.

[Wayne Kinney]

I think we need more info on the screen, or is a general question? If it is real glass, a simple glass cutter should work. You can touch up with a dremel tool and a diamond grinding disk, but use water.