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Joe gwinn

In article , Ed Huntress
wrote:

On Fri, 01 May 2015 20:46:59 +0100, David Billington
wrote:

On 01/05/15 20:26, Ed Huntress wrote:
On Fri, 01 May 2015 08:33:36 -0700, wrote:

On Thu, 30 Apr 2015 21:42:45 -0400, Ed Huntress
wrote:

On Thu, 30 Apr 2015 18:16:06 -0700, wrote:

On Thu, 30 Apr 2015 15:57:05 -0700 (PDT), Gerry
wrote:

On Thursday, April 30, 2015 at 5:25:46 PM UTC-5,
wrote:
Not exactly metalworking. I needed to make a replacement glass piece
for a camera because I removed the IR/UV filter and the space needed
filling for proper focusing. I used a 1mm glass slide, the type made
for microscopes. The piece needed to be 8 x 9 mm. I mamaged to get one
and then discovered I had scratched it. So I tried again and was
rewarded with a scratch free piece. I was surprised how hard it was to
cut this glass, for it to break where I wanted it to, and finally
figured out how to score it properly. I hope I never need to do this
again.
Eric
Years ago I did lapidary work. While most everything was done with
stone I used to play with glass sometimes. I was able to cut glass
with a diamond saw, grind to shape using grinding and sanding wheels
with water drip to keep things cool. The glass was mounted to dop
sticks using what was called dop wax which was almost like old style
sealing wax used with stamps for letters and such. Maybe you can find
someone close by that is into lapidary work for help? A designing
jeweler may point you in the right direction. I'd bet that your local
glass shop has wet belt sanders with different grit belts for
finishing glass edges. Maybe they would let you use their belt sanders
for your project?
Greetings Gerry,
I have done lapidary work and even have the stuff still to do it. My
stone saw is just not set up to cut stuff so small and the glass is
more brittle than the stones I have cut in the past. I did finish off
the piece by using one of my diamond wheels on my slow speed carbide
grinding/lapping machine. I was actually surprised at how fragile the
glass was. I have cut glass tiles in the past year with one of my
diamond cutting discs cooled and lubricated with water and had no
trouble. But the little pieces I just did were much more prone to
chipping and cracking than the tiles and the diamond cutting disc
caused too much edge chipping, even when run quite slow.
Thanks,
Eric
Oh, yeah, I forgot to mention that there are fused-quartz slides, too.
You generally can't tell the difference by looking at them and you'd
know it if you bought them in a package. They have very high UV
transmittance but I have no idea how they cut.
I wish they were quartz because of the toughness and UV transmission.
The filter I removed was a two piece affair. At first I wondered why
two pieces of glass were cemented together and I thought maybe it was
for strength. But I think it is because the clear piece of glass is to
filter out UV. This would be good because CCD sensors also see into
the UV spectrum a ways and I would like to get some pictures of
reflected UV from flowers and such. Tonight I will be installing the
glass and doing any adjusting of the sensor location that may need to
be done. Tomorrow night I hope it will all be back tohether so I can
try it out at a bonfire.
Eric
Good luck. I never priced the quartz slides before but I just looked
them up -- which I should have done before posting. Yipes, they're
expensive.

I see that they're also said to be available in borosilicate glass
(the stuff old Pyrex was made from -- today, it's tempered soda lime
glass), but I didn't look for a supplier. Borosilicate is still
another kettle of fish.

I posted this before, apparently Pyrex is still made with borosilicate
in Europe, it seems the US made stuff is tempered soda lime glass, I
guess to reduce the price.

Right. We can get the borosilicate cookware, but my recollection is
that it's imported from Europe. The Pyrex cookware usually sold in the
US is now tempered soda lime glass.

Yes. The "Pyrex" brand fell into the wrong hands after Corning nearly
died when the dot-com bubble burst, and was selling off "non-core"
businesses.

The new company is busily destroying the Pyrex brand.

Certainly all the Pyrex I have here in the UK
is clear and doesn't have the green cast often seen in soda lime from
iron and when dropped doesn't break like a tempered glass DAMHIK.

Iggy had a bad experience with a relatively new Pyrex baking dish. It
shattered in the oven. I'm hanging on to my old stuff, some of which
dates back to the '60s.

Iggy is not alone. Lots of horror stories on the web now.

There are now people selling borosilicate glassware, by that name,

And I'm hanging onto my old stuff too.

Joe Gwinn