Hi Enadrew, and best wished
Can you give me a contact for Thermoshield. Now that it is clear that Ken
Heine left for unlimited holidays, I am desesperate to obtain new crucibles
since I am working with the last one. Also, any idea where tungsten heating
filaments could be manufactured ?
All the bast
Nick
At 20:35 16/11/2005 -0800, you wrote:
>To follow up on what Martin wrote, Thermoshield has made four
>furnaces for Menlo Park over the years, the most recent was last
>year. All work well and his prices are reasonable. The power
>supplies were built in house, but he may do that as well.
>
>We monitor furnace temperatures with an Accufiber optical lightpipe
>(IR) made by Luxtron instead of a thermocouple. It works very well
>and you don't have to worry about keeping it in contact with the
>crucible. We have our crucibles made with a 1/4" nipple on the
>bottom to guide the lightpipe. They no longer make the one we use,
>but have a new "better, cheaper, faster" model on their web site.
>Ours does not measure temperatures below 400°C, which is fine for us,
>but may impact low-T thermochronology. Their new Photrix system
>looks like it will measure down to 125°C, but you would have to work
>with them to mount it on a vacuum feedtrough and fit it in the furnace.
>
>Let me know if you want more info.
>
>Andy
>____________
>Andrew Calvert
>Volcano Hazards Team
>US Geological Survey
>345 Middlefield Road, MS-937
>Menlo Park, CA 94025
>650-329-5276 office
>650-329-4664 fax
>[log in to unmask]
>
>
>
>On Nov 16, 2005, at 2:18 PM, Martin S. Wong wrote:
>
>>Hi all,
>>Our experience at UC Santa Barbara has been the same with regards
>>to Ken Heine, so we've looked for other resources. We recently had
>>a coiled heater element that sagged and contacted the heat shield,
>>melting part of it. A company called Thermosheild in Palo Alto,
>>CA, was able to provide new furnace sheilding based on our
>>measurements of the Heine furnace design. Although I'm not at
>>Santa Barbara now, reports are that the new heat shielding was of
>>superior design to the Heine version. Contact info for
>>thermoshield is:
>>Thermo Shield
>>722 Orange Avenue
>>Los Altos, CA 94022-3849
>>ph: 650-941-5230
>>fax: 650-941-2568
>>e-mail: [log in to unmask]
>>Main contact: Bernard Scheiff, [log in to unmask]
>>http://www.thermoshld.com/
>>
>>Thermoshield also was able to provide moly tubing for fabrication
>>of moly crucibles. The moly tubing was about $330 from
>>thermoshield for appropriate length and gauge. We had our
>>crucibles fabricated by Applied Fusion (at Andy Calvert's
>>suggestion from USGS in Menlo), which cost another $375 per
>>crucible (so total cost was about $700 per crucible if bought in
>>reasonable numbers and the moly crucibles seem to last longer than
>>the Niobium ones). Their contact info is:
>>Applied Fusion
>>1915 Republic Avenue
>>San Leandro, CA 94577
>>ph: 510-351-8314
>>fax: 510-351-0692
>>[log in to unmask]
>>Ron Musgrove - CEO
>>Ron Holton - VP Fabrication
>>http://www.appliedfusioninc.com/
>>
>>Dave - in response to your question on thermocouples, we had a
>>custom thermocouple made by our physics machine shop which
>>consisted of an Omega unsheathed fine gauged type C thermocouple
>>that comes with a bead at the top (T5R and T3R series). The bare
>>wires can be fed through a standard 2-hole ceramic thermocouple
>>insulator, also available from Omega. We then designed a teflon
>>cylinder with a blind hole drilled into the top designed to hold
>>the thermocouple insulator. The blind hole had small holes in
>>either side to feed the thermcouple wires through the blind hole to
>>the outside of the cylinder. The teflon cylinder is slotted at the
>>base to fit into a standard conflat flange electrical feedthrough.
>>We put small set screws into the electrical contacts to attach the
>>thermocouple wires into each feedthrough and covered the teflon
>>base with shrink wrap to avoid having the thermocouple wires
>>touching anything. If the thermocouple breaks, you can just swap
>>out the beaded wire, which is a stock item from Omege for about $60- $80,
>>which is much cheaper than what Heine was charging for repairs
>>and with a faster turnaround time. It sounds a bit more
>>complicated than it actually is. I can have someone take some
>>photos if you are interested.
>>
>>Hope this is helpful.
>>
>>Cheers,
>>Martin
>>
>>--
>>Martin Wong [log in to unmask]
>>Graduate Student www.uweb.ucsb.edu/~mwong
>>Dept. of Geological Sciences Phone: (805)893-2782
>>UC Santa Barbara Fax: (805)893-2314
>>Santa Barbara, CA 93106
>>
>>Current contact info:
>>Visiting Assistant Professor
>>Department of Geology Colgate University 13 Oak Drive Hamilton,
>>NY 13346
>>
>>Ph 315/228-7203 Fax 315/228-7187 [log in to unmask]
*********************************************
Dr Nicolas ARNAUD, PhD
Chargé de recherche CNRS
Directeur de la Fédération de Recherche 2035-ISTEEM
UMR 5573 CNRS, Laboratoire de Dynamique de la Lithosphère (LDL).
Groupe de Géochronologie
CC 066
I S T E E M - U S T L
Place Eugène Bataillon
34095 Montpellier Cedex 5
FRANCE
Tel: (33 0) 467143729
Fax: (33 0) 467143729
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