First, if you have 12mm or 20mm spinners which you are not using, then
machine a plug for the top and bottom with a 5mm hole. You can then use
these spinners for 5mm tubes.
Second, if you don't have larger bore spinners, machine a new spinner out
of Delrin. The brown Vespial (sp?) from DuPont is more expensive than
gold. It was chosen so that the temperature coefficients for expansion are
closest to Aluminum, which is what the spinner shelf is made from. If you
need to do extreme VT then you can machine an Aluminum spinner with Delrin
plugs.
Each NT spinner shelf required a custom machined spinner. The process was
to rough machine spinners out of Vespial and let them sit in the storeroom
for several months. This let the material get out all of its tendency to
bend. Then the spinners were machined to the individual spinner shelf.
The spinners measurements were recorded in the customer's files in case
he ever ordered another one. It may be too much to ask Bruker to come up
with the information and make another one.
Almost any machinist can make one of these things with trial and error.
Even I can do it with lots of time and materials. A GOOD machinist can do
it the first time with only a couple of trials to see if it spins. Have
them overcut the spinner's angle into the body so that there is no bumps at
the junction.
woody@acornnmr.com
www.acornnmr.com
ftp.acornnmr.com
-----Original Message-----
From: London.Robert [SMTP:london@niehs.nih.gov]
Sent: Friday, June 27, 1997 10:32 AM
To: 'ammrl'
Subject: Spinners anyone?
We are looking for replacement spinners for a standard bore NT-360
spectrometer. Any suggestions?
Thanks,
Bob London