From: Jim Burt (jim.burt@infocus.com)
Date: Fri Feb 18 2000 - 20:05:20 EET

I hate it when I do this.......below is a message I sent out a few weeks ago
asking for help with a ceramics problem I thought I had. As it turned out,
my problem was inaccurate feedback. There is no thermal problem with the
parts supplied by Dr. Stucker. Apparently the only problem is a difference
in coefficient of thermal expansion between Dr. Stucker's material and the
glass we cement into the base, I think I can fix that. But until I am shown
some real data, I am not even certain about that at this point.

Anyway, the point is that I am sorry for the incorrect information I put out
and I am very grateful and impressed with all of the responses I received
with good suggestions. I have at least 6-8 optional methods to try. It may
take me a while but I hope to make contact with all who responded. I owe
files to several of you and will get them out as time allows...

Those people that complain about this list should ask for assistance once in
a while...it is humbling.

Thanks again,
Folks, I am looking for alternative methods/vendors for prototyping ceramic
lamp bases. They operate in a 500-700 deg C environment. These are nor
simply 2D with some through holes or slots. These parts can get fairly
complex, for ceramics. Generally I machine them from Macor but can make only
2 a day on our CNC. I may need 100 pretty soon and at about 2/ day I am
looking at 50 work days, with no scrap...not nearly acceptable.

I have tried to have some made by the SLS process (DTM, thru Brent Stucker,
Univ. Rhode Island), and the parts were good but could not handle elevated
temperatures. I still think that is a viable approach and if someone has
more info I would be most appreciative. Since I don't know the sintering
temperature of the laser, and a heck of a lot of other things, there may /
may not be a material that will work by this process.

If any of you would like to quote some of these, please let me know. I do
not generate drawings unless forced into it (for prototype parts), so you
need to be able to take IGES data.

Thanks a lot.


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