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jantman
13-Jan-2004, 15:44
I have a question for whomever has an idea. I'm making a new GG for my Cambo 8x10. I read the article in May/June 2003 Photo Techniques, and ordered 5 and 3 micron aluminum oxide from Willmann-Bell. I'll get normal float window glass from a local glass store.

However, I'd also like to make a ruled GG. Any ideas? I'd rather not have to draw every line on by hand. Can anyone think of an easier way? Maybe some sort of printed overlay to somehow stick to it? Is there any "real" way to do it?

Thanks.

PS - I ordered a pound of each grit (a "lifetime supply") so if anyone else wants a GG, just ask me and I'll figure a good price.

David A. Goldfarb
13-Jan-2004, 16:05
How many lines do you need? I've just penciled them in using a metal ruler, one inch wide, and a T-square, so looking horizontally, I have three lines one inch apart on the left and right sides, two on the top and bottom, a small "+" in the center surrounded by an open area. If you have a T-square that's a convenient width, you can use it without a ruler.

Colin Carron
13-Jan-2004, 16:10
Jason, you may get answers more to your liking than this but I drew a grid on my ground glass with a sharp pencil. Mistakes can be removed with a soft rubber. As I use roll film holders the grid was mostly to show the 6x7 and 6x9 frame sizes. I find a complete grid distracting.

Conrad Hoffman
13-Jan-2004, 16:10
You can draw up an overlay in CAD or other drawing programs, then print it on clear transparancy material. Makes experimenting with different spacings easy. OTOH, nothing's as nice as delicate lines ruled on the ground surface itself, if done well.

jantman
13-Jan-2004, 16:39
Thanks for the speedy replies. I guess I'll give both methods a try. The pencil is what I've heard most often, but I was thinking of a full ruled grid like the glasses that they sell. I guess, on second thought, I don't really need that much.

I'll probably also put center marks and format marks. Probably just colored dots for smaller formats. I'll try a few different approaches on different glasses. For the transparency stuff, I can get some from school. They still use that archaic stuff. I'll probably cut it to size and just lay it over the glass, maybe use a little glue. If I can get it to stay on its own, that probably makes the most sense, because I could use one glass and just interchange the overlays.

Thanks, everyone.

matthew blais
13-Jan-2004, 17:57
I would think that clear "static cling" film (like what they put in your windshield after oil change) would work great. I would try a Promotional Items Distributor (check under promo items/advertising in the Yel.pgs. & ask for a sample), i.e.or major paper/label/sign supply company. What i don't know is if it will take ink from either graphic pen or inkjet but assume not pencil. Since they imprint these for end user, should take some type ink.

But they cling without glue or tape to glass very well and you could have several for backups...just my thought. Good luck.

David R Munson
13-Jan-2004, 22:14
Initially, I would suggest just making an overlay using sheet acetate and a technical pen. That way you can experiment with different grid sizes, and if you don't mind having the overlay there in use, you don't necessarily ever have to do anything more than that. Or, if you decide that you don't like having a grid after all, just take the overlay off and forget about it. I've put grids on a couple ground glasses using a steel rule and india ink in a *very* fine Rapidograph. Works well, though you have to be careful not to make any smudges.

evan clarke
14-Jan-2004, 05:41
HI, Use a carbide or diamond tipped scribe, it will cut into the glass itself. Don't make a mistake, though!! 8))

Dave Mueller
14-Jan-2004, 09:48
HI Jason,

1) I'll take you up on your offer for some grit!

2) The local craft store has paint for glass that you cure in the oven. My idea was to print the grid you want on normal paper, and lay the gg on top (ground side up). I was thinking of using thin thread or dental floss and dipping the thread in a puddle of paint, and then gently stretching it across the glass, using the pattern as a guide. Unfortunately, this limits you to straight lines with an easy pattern.

3) There is a technique for making printed circuit boards using a laser printer or copier. Instead of paper you use mylar (or one of the expensive plastic sheets made for this). Put the mylar image side down onto the board (or gg), and use a household iron to transfer the image. It's pretty tough once transferred, I think it should be OK considering the amount of abuse a gg should NOT be seeing :-) I've made a few circuit boards this way, it takes some practice but you can get really nice artwork this way, certainly good enough for a grid on a gg.

jantman
14-Jan-2004, 15:03
I'm sorry if there was a misunderstanding, but I said if anyone wants a GG, as in a finished glass. However, if the grit is what everybody's interested in, once I'm done with my six sheets, I'll see what I have left and consider reselling it.

The mylar idea sounds good, I could probably just put it between two sheets of old mat board and stick it in my dry mount press. If I can find some mylar, I'll try it.

I ordered the grit yesterday, it should probably be here next week or so. My local glass cutter usually has an overnight turnover, but I figure my order will be done in the next two days. So, if it's all here next week, that weekend I'll start grinding the glass and tell you guys how it worked out.

Thanks for all the advice. I think that an overlay or transfer will be the way to go.

PS - Dave, do you know where I could get sheets of mylar?

Dave Mueller
14-Jan-2004, 19:50
"I think this is the beginning of a beautiful friendship."

Sorry for the misundertanding, but I'll be making a 4x5 gg.

I have a lifetime supply of drafting films (vellum and mylar) that I got from a copy house that went out of business. I'll try to run a piece through the copier at work and see what happens. For the pcbs, I used overhead transparency film from an office supply store before I inherited the boxes of drafting film. I think almost any thin film will work as long as it doesn't melt in the copier or with the iron and it has a surface the toner will stick to but not be absorbed by. Thinking about it, you could probably use an inkjet printer and the paper made for making iron-on tee shirts.

Or, if you want to just email me your address, I'll cut up a few sheets of each into 11x14 pieces and mail them to you.

jantman
15-Jan-2004, 08:39
Dave,

I ordered the glass yesterday. The grit should be here next week. Maybe we can work out a trade - grit for some overlay sheets.

I'll get back to you next week.

jantman
16-Jan-2004, 15:39
Well, the grit arrived today. $25 for two pounds, including shipping, and it gets here in two days! talk about service.

well...the shipping was only from VA to NJ.

Today is Friday. I'll pick up the glass on monday if they're open, and start working on it. If they're not open, it might be until mid-way next week before I get to working on it.

jantman
25-Jan-2004, 08:31
I finished grinding my first two sheets. They're beautiful. I've never seen one so smooth or bright before. They took an hour each, about 30 minutes with 5 micron and 30 minutes with 3 micron. I followed the instructions in Dick Dokas' article in May/June 2003 Photo Techniques.

I used less than 3/4 of a teaspoon of each grit (per sheet), in 1/8 teaspoon amounts. Since I barely made a dent in the pound that I bought, if anyone would like to discuss buying some from me, send me an e-mail.

One tip - my local glass shop, even though I brought in the camera back and asked them to cut the sheets to fit, cut them a bit on the large side - they didn't seat all the way down on one side. I used some fine sandpaper (black aluminum oxide emery fabric, about #500 I think). This made quick work of it - less than a minutes' grind worked.

Tom Johnston
16-Mar-2004, 14:12
Jason,

I realize that this thread is a little old but, like you have already done, I am going to make my own ground glass. I have read the article that you mentioned and when searching for a source of aluminum oxide, I found this thread. You mention that your aluminum oxide from Willmann-Bell. I found them on the internet at http://www.willbell.com but, at least at this webpage, only books on optics are sold. Would you be kind enough to link me to where I can order aluminum oxide?

Thanks

Carlos
16-Mar-2004, 15:36
Tom,

You have to call Willmann-Bell because it is not on their web site. I just received the 5 micron and 3 micron. You have three options ( in respect of the amount). Call them on the phone.

Good luck!

jantman
16-Mar-2004, 15:42
Carlos speaks the truth.

You have to give them a call.

Tom Johnston
16-Mar-2004, 15:43
Thanks. I'll do that.

Carlos
16-Mar-2004, 15:50
By the way ... Do not expect great improvement in brightness. I just did my ground glass and I am thinking of adding a fresnel to the gg. It is cheaper to make your own gg.

Murray
6-Jul-2004, 09:47
I made a few with 400-500 blend (13-17 micron?) SiC, then read the article on aluminum oxide.

I got some 5 micron and am amazed how much slower it is to grind...but I guess that's the price one pays.

If it's not brighter, then hopefully the smaller surface imperfections are an improvement, I am starting to notice how pitted the 400-500 SiC looks under a loupe :O(

I can see how the glass is cut slightly 'wrong'. Our glass cutter calibration has never been right since we installed it, nor can I fix it. It seems the self-adhesive ruler tape was misapplied.

When I measure pre-cut, pre-washed glass right out of the box from the glass manufacturer, I am amazed that is right on. I have never had a piece that is 'off' by even a measureable amount.

Murray

Murray