Good stuff, Randy! When I get some time, I'll make some comparisons of a 3 micron aluminum oxide glass, a Sinar glass, a Maxwell screen, and a Beattie Intenscreen +.
Good stuff, Randy! When I get some time, I'll make some comparisons of a 3 micron aluminum oxide glass, a Sinar glass, a Maxwell screen, and a Beattie Intenscreen +.
“You often feel tired, not because you've done too much, but because you've done too little of what sparks a light in you.”
― Alexander Den Heijer, Nothing You Don't Already Know
Reviewing some older DIY threads. You guys amaze me. I tend to think of float glass as a flatness standard and here y'all
Are talking about flattening it!
Two possibly dumb ideas:
Sandpaper will grind glass too. I used it because it was available. To make grid lines, draw them on with a pencil and a straight edge.
Scribing grid lines with a needle sounds to me like an invitation for the glass to snap on those lines.
A couple more dumb ideas: don't use glass, use acrylic (it scratches easily!), or waxed or oiled paper (durability issues) or a matte or flat varnish on glass etc.
Okay. I finally got around t ordering this. I got the one Peter recommended (called pre-polishing), and after I made the order the invoice showed it as 3 micron powder (.0001) rather than 5. I hope it is not too fine!
Unfortunately, I am off on a work trip Friday, so will not have a chance to try it till I return in early November.
Made a new 8X10 GG last night from Home Depot 8X10 which exactly fits 8X10
I made cut corners first, as I like them. First to check aperture and secondly to make less suction pulling in dust
Used what I had already 600 grit from this source which sells to telescope mirror makers, lot of good info there
https://stellafane.org/tm/atm/mirror...20Size%20Table
Used the GG today, it is very nice, but I plan to use even finer grit and see what I like
I have made at least 5 GG up to 11X14
Tin Can
Have 400, 600 and 1000 (silicon carbide). Especially for smaller glasses, such as a little ground glass for a Rolleicord, I use first 600 and then the 1000 to get a smooth surface.
Ground Glass XVI by Ron (Netherlands), on Flickr
this one was done for a Deckrullo camera which had rounded corners:
Ground Glass VIII - Nettel Deckrullo by Ron (Netherlands), on Flickr
Last edited by Ron (Netherlands); 9-May-2021 at 04:48.
I just made this one for my B&J 5x7 using aluminum oxide from gotgrit.com and I am very pleased with how it turned out. Image is nice and clear and I see very obviously much finer granularity when compared to the stock gg on my Cambo, and it's in a completely different league than the crummy vintage one it is replacing.
Since the oxide grit is stupidly cheap in the tiny quantities I needed for this (1/4 pound will probably make 100 ground glasses), I got 5 different grits, ranging from 25 micron to 5 micron. I didn't even get down to 5 micron with this. I went from 25, to 15, to 12 and then I was happy enough with it, I didn't see any reason to go further. Next one I make, I'll take it all the way down to 5 micron and see if it makes enough difference to be worth the extra time. All told, it really didn't take as long as expected, maybe a half hour grinding at 25 micron got a functional gg, and just a bit longer with the finer grits to finish it off. Maybe 2 hours work total, that includes washing it off and drying it several times to check on the progress.
Thanks for the report!
“You often feel tired, not because you've done too much, but because you've done too little of what sparks a light in you.”
― Alexander Den Heijer, Nothing You Don't Already Know
I started making my own ground glasses during WWII when it was difficult to find it readymade. I make 2 at a time using one to grind the other.. I usually cut the corners before grinding, but have been known to do so after grinding. I have also made them using spray-on window frosting, which works well, but is fragile.
I've not tried the spray on method. Other than the fragility, how does it compare?
“You often feel tired, not because you've done too much, but because you've done too little of what sparks a light in you.”
― Alexander Den Heijer, Nothing You Don't Already Know
Bookmarks