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Old 03-20-2004, 11:03 AM
Kurt Walrath's Avatar
Kurt Walrath Kurt Walrath is offline
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Join Date: Apr 2002
Location: Corning
Posts: 155
Kurt Walrath is on a distinguished road
Yeah..step to 2270 for cook.
as for squeeze, I think I recall Pete suggesting 1900 as a
figure to use back on Brads board when I 1st got hot.
Dropping to 1900 and immediately going up to working temp
left some bubbles and if I'm trying to blow asap I need to
hold at 1900 for a couple of hours as I recall. But I just
stop my program at 1900 to save electricity. my furnace
will go from 1900 to 2100 in a little over an hour. About the time
it takes me to cut color bar and set up to blow.

I find that with my pot once the level of glass is below the
straight sides I have trouble with gathering bubbles on the
3rd and 4th gathers. All the heat in my furnace has to pass
through the pot, there's no radiant source on the surface of
the glass, so the glass that trails off tends to trap small bubbles
that would dissapate much faster in a furnace that had heat
coming in from the top. This would be one of the worst flaws in
my furnace design but I did it to protect the elements from
the batch. in my furnace a gather at 2100 feels really cold
compared to glass coming out of a gas fired furnace that runs
colder temps. It's not an issue for regular blowing, but making
an avolio is hard because the bit just isn't as hot. A goblet maker
would probably have fits with my furnace. I tried to raise the
working temp but ran into reboil problems at around 2140 as
I recall.

So anyway I usually charge once I get into the bottom 3rd
of the pot and don't fully empty unless I'm shutting down.
I'm actually going to try to use that last bit tonite when I blow.
I've been working alone making 2 gather pieces and I want to
see if I can get more days out of a pot of glass than in the past.

Kurt
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