Re: ATM Roller bearing material

[Chris Westland <westland@uxmail.ust.hk>]

andyman wrote:
> 
> >Hi Mel & Bob:
> >
> >I am in the process of starting a stepper driven Dobsonian, with Hurst
> >steppers (initially using a Dob Driver II that I purchased, but
> >ultimately moving to a computer controlled setup) and am interested
> >again in eliciting your experiences and thoughts (and those of the list
> >members) on the bearing material.
> >
>    Try silicon nitride balls.   They are stiffer than ANY metal,
> corrosion-proof, incredibly round (CERBEC), and if you can spend a little
> extra, call a supplier (SKF, MPB, Torrington Company) and ask for CERBEC
> "sir-beck" bearing balls. They are more expensive than metal,    but if 'ya
> want state-of-the-art....
>     -Andyman


Thanks Andy, I'll give them a call.  I would like rollers, though,
rather than balls, since I want to drive the scope.  Do they sell
rollers  (I seem to recall you saying that you were putting balls on a
rod ... are you trying this with silicon nitride balls?)

On another topic, did you agree with Larry Manuel on the position of the
field stops in the Naglers.  Seems to provide a good reason for my
measurement discrepancies.

As always

-c