Dear Bumers:
Thank you very much for the information on rotors for Bruker=20
probes that many of you have sent me. Since there were people=20
interested in the subject I intended to make a summary. However, as=20
you can judge by yourself, it was not possible because there were=20
some contradictory opinions. Therefore, I just added to this=20
letter all the information I have received.
As a conclusion I should say that people are satisfied with=20
the rotors manufactured by the three companies.=20
You will find after the letter the quotation for the=20
rotors given by the companies.
The letters:
1) So we have used Bruker and RotoTec, and I should say don't=20
differ much in performance in terms of spinning speed. The only=20
difference I noticed is that the internal diameter for RotoTec is=20
perhaps slightly smaller than the one from Bruker. Therefore, we=20
used RotoTec rotors with used BN caps for low temperature work.=20
Last time i checked prices <about half a year ago> there wasnt=20
much difference for these two, though never heard of Cerobear=20
before. Could you please send me fax number or e-mail address for=20
Cerobear.=20
2) We have purchased a few rotors from RotoTech. Our initial=20
impression is that they seem to work well. However, we have not=20
had time to test them thoroughly.
3) We have a MSL 400 and also buy a great quantity of rotors. At=20
the last ENC conference, I spoke with the owner of CeroBear who=20
said that Bruker is actually selling their rotors. Cerobear sells=20
them directly (which for some reason are more expensive) and sells=20
them to Bruker. These rotors are pure white and perform quite=20
well. No spinning problems for us at all. I've checked around and=20
have found the Bruker prices to be the best. Bruker had a previous=20
supplier which provided yellowish rotors - these too worked well.
4) We've had good results using Rototec rotors in our Bruker 7mm=20
MAS probe. I think that they are now or will be shortly sold by=20
Wilmad. Sorry, I've never heard of Cerobear.=20
5) I have been using Cerobear rotors for the last 5 years and have=20
had no problems at all with them. Of course any rotor can break=20
at any time.
6) I used Bruker and Rototec 7 mm rotors on our MSL200. The=20
quality of the rotors of these two companies are very similar but=20
the price is quite different. Rototec rotors are cheaper than=20
Bruker rotors.=20
7) I saw your note to BUM. There are only two manufacturers of=20
rotors for Bruker MAS probes, Bruker and Cerobear. Rototec are=20
dealers who buy from Cerobear. We have checked the accuracy of both=20
makes and there is not much to choose between the two, although the=20
Bruker rotors seemed to us to give slightly better probe tuning.
PRICES:
CEROBEAR (Fax: 49-2407-96224):=20
5 (five) ZIRCONIA rotors DM 1750
10 (ten) Kel-f caps DM 400
BRUKER (in Germany)
five Zirconia rotors +=20
ten Kel-f caps + five BN caps DM 3,680
ROTOTEC (contact Wilmad. www.wilmad.com):=20
1 (one) ZrO2 rotor(buying 5+) $ 345.50
10 (ten) Kel-f Caps $ 327.50
Best regards.
Dr. Carlos A. Steren
FAMAF
Univ. Nac. de C=A2rdoba
5000 C=A2rdoba
ARGENTINA
FAX: 54-51-681862