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Re: Ovens.

On 3/29/96, Morgan said:
I've worked with several ovens when I was blessed enough to be teaching at
Penland with Jacob.  During the last workshop I think we had four ovens going
at once (it's great that you can be heating / outgassing in one location and
"pumping" right beside it).  The oven I have and use now for single electrode
stuff was made by David Wilson and is similar to some drawings that Jake has
(I don't know if they are copywrited or not).  Having worked with several
ovens now, here are some tips:  bigger is better (in fact Ed Biggers brought
his biggest oven to the workshop - maybe 3' by 5' inside - )  it doesn't cost
that much more to heat big areas than smaller areas;  use 120 V electricity:
 you're sticking your hands inside this box with power wires running all over
the outside and inside - 120 V hurts,  220V can very easily kill you  (these
heaters are vailable through elec.stove repair places),  if you think you're
going to need a large oven,  think about making it so that you can lift the
top off with some kind of cable thing, and let the glass lie on some
non-moving table.  Try to think (plan) how you are going to be able to get to
each electrode to heat it with your inductive heater  (how about access
pannels?) (remeber how much it hurts to stick your hand inside an oven).
I think there are some great theoritical benifits of oven pumping.  In real
life,however,  alot of it doesn't seem to work out as well as normal
bombarding though; but for real low production/one offs I think it's how I
would go (and obviously the only way to go with single electrode stuff).  
Jeff's adaptation is interesting, but I think has some techinical flaws.
 (Jeff please help me understand)

My reply: 
Can't help you understand if I don't know what you are misunderstanding.
Please be more specific about the "technical flaws" (:-{) you think it has
(?!!) I sure don't see any, it works like a charm for the past 6+ years, and
my tubes have failure and fading rates on the order of 1% of those others
report. (Excuse my being sensitive!!!) This is much chaper to operate, at the
cost of electricity today, the process is much quicker to set up and to run
(no oven thermal inertia to slow you down), and more flexible since you can
run any type of tube configuration. Can keep up with electrical bombarding on
most types of tubes, except that I do more processing than they do because I
can see the additional processing necessary and they just go up to
temperature and automatically back off after a short while. Have forwarded my
old messages on this to you.
Jeff