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vickersdc
27-Nov-2009, 15:20
I recently bought an 18cm x 24cm FKD camera, and when it arrived the lens had not been securely packed; during transit it had smashed the original ground glass into hundreds of pieces.

To be fair to the seller, he is sending me a new one, but in the mean time I thought it was a good opportunity to make my own. My wife has just taken up making stained glass, so she cut some 2mm glass to size and clipped the corners.

Using 600grit Silicon Carbide, it took about 1/2 hour to do, all that's left is to draw the lines on. The glass is really bright and it'll be interesting to compare it against the new one that it on it's way to me!

http://1.bp.blogspot.com/_FC6ZcPSvMqc/SxBMbYn1H-I/AAAAAAAAAYA/Zefj5wWOc34/s320/DSC01897.JPG http://3.bp.blogspot.com/_FC6ZcPSvMqc/SxBJI-Cp2wI/AAAAAAAAAX4/e4N_lm7iVbs/s200/DSC01904.JPG

Robert Hughes
27-Nov-2009, 15:57
Very nice! Sometimes those DYI projects are the most satisfying... :)

Uncle Jim
27-Nov-2009, 16:26
Hi Vic,

I've made a number of ground glasses for various cameras. 600 is a little course, and you might want to try refining it with some finer grits, as it can make quite a difference. I still have a lot of grits left from when I was making telescope mirrors an use a much finer grit.

uncle jim

Pete Watkins
27-Nov-2009, 16:29
Hi Vick,
Where did you get the silicon carbide? I assume that it was in the U.K.
Best wishes,
Pete.

vickersdc
27-Nov-2009, 23:09
Hi Vick,
Where did you get the silicon carbide? I assume that it was in the U.K.
Best wishes,
Pete.

I got it from a stone polishing place down in Cornwall. The guy's name is Paul Jeffery, and I would buy from him again; the first lot that was sent out never arrived, and after phoning him about it, he just sent another lot the same day (which arrived the following morning).

The link to the silicon carbide is here (http://www.stonepolishing.co.uk/product-SILICON%20CARBIDE%20600-1350.htm). I ordered the 250g bag as I just know I'll be making more screens in the future, but 125g is more than enough for several screens anyway. Postage was £2.

Cheers,
David.

PS: (Uncle Jim), Would Tin Oxide polishing powder do the trick?

Mike1234
28-Nov-2009, 02:53
Anyone ever tried attaching a metal plate with raised edges to a randon orbit sander, mounting the contraption plate-side-up, and setting the glass onto the dry powder? It sure seems like an easier way to make a GG.

vickersdc
28-Nov-2009, 05:40
Here's a quick shot taken with a point & shoot this morning of the result...


http://4.bp.blogspot.com/_FC6ZcPSvMqc/SxEVnPzYlWI/AAAAAAAAAYI/RXa4-wfjaUM/s320/DSC01906.JPG

Pete Watkins
28-Nov-2009, 11:30
Thanks for your help.
Pete.

vickersdc
29-Nov-2009, 03:41
Actually, if anyone is interested I'd be willing to grind some glass if someone needed one for their camera (although you'd have to cover my costs!). I've since learnt a couple of new things about grinding glass and 1) I don't need anymore ground glass right now, but it might help someone out, and 2) I'd be interested to see what other people think about it.

If you might be interested, PM me.

Uncle Jim
7-Dec-2009, 22:55
Hi Vick,

Sorry to be so long answering, but I've been away. I have been using Aluminum Oxide in grits of
15 and 5 micron. I also have some 30 micron, which is about 600 grit, that I am going to try on the three 8 x 10 ground glasses I will be working on tomorrow. I'll see if it is faster than 15 micron stuff that I have been using, but I still plan on finishing with the 5 micron powder (which is about 1200 grit). Tin oxide is a polishing compound not a grinding one, and would just polish your glass again.

uncle jim

Uncle Jim
10-Dec-2009, 17:37
Hi,

I made an error in my last post. It's been a year or more since I made a ground glass, and I misquoted the Abrasives. I was using 9 and 5 micron aluminum oxide. Don't use the 30 micron stuff as it is way too course. I ground 3 glasses yesterday in 8 x 10 size using 15 micron and then finishing with 5 micron. They turned out beautiful. Also reground the glass from my Agfa/Ansco 8 x 10 using the 9 micron powder to even out the figure. Looks much better. So now I have 4 finished 8 x 10 ground glasses. If there are any questions, please let me know.

uncle jim

JRFrench
11-Dec-2009, 02:02
I've just ground my own using 5 and 3 micron alu oxide powder, it took a while (about 2 hours of casual work for a 4x5) but it seems to work well, I don't have much to compare to at the moment. It only has a very slight hint of texture under an 8x loupe.

I followed this process: http://www.dokasphotos.com/techniques/ground_glass/

Also for abrasives, these guys are very cheap, and prompt with shipping: http://www.willbell.com/ATMSupplies/ATM_Supplies.htm

imagedowser
11-Dec-2009, 07:12
If you are going to make your own gg, take your back to the glass person and have it cut to fit. A drag to have a beautiful gg just a bit too big... Unless, of course, you are skilled at glass cutting, which is a fun skill to have... The clipped corner is, I've found to be hard to do well... any glass artisans out there have any tricks to do an accurate and clean corner clip? Buy the way, thinner glass is lighter glass and it's been said pyrex glass makes a more durable and optically slightly better gg. Have not tried it yet, more expensive/harder to find, a touch heavier IMO. Btw any glass shop can cut a "frosted" glass that works very well, very inexpensive, pop it right in and focus... Learned that from Eddie.

vickersdc
11-Dec-2009, 08:19
The clipped corners are not too bad to do as long as you have a decent glass cutter, and the proper shaped 'pliers' to break it with. After that, then you can just grind the edges down smooth and slightly round off the remaining corners.

David.

salihonba
4-Jan-2010, 18:14
Here is my two cents, no ground work needed.
prepare your transparent acrylic plate in gg size, easily cut and clipped.
a laminating sheet bigger than gg, that used to laminating photos, id cards, name plates, made in two semi transparent plastic sheet.
some baby lotion

Now cut laminating sheet according to gg size, we need only one piece
then dip some baby lotion on gg plate, carefully cover the sheet on it, let the matte surface face up.
squeeze the air bubble out, by your finger,from center to the edge, till there is no air at all.

that's it, a perfect gg plate!!

sha_hong
16-Jan-2010, 09:29
Use the optical glass will be better.
The finest groud glass is made by chemical method.