ATM JMI focuser... problems...

["Benoit Schillings" <benoit@be.com>]

I actually had some bad experiences with the JMI focuser... I hang a 
lot
of stuff on the focuser (AO-7 + ST8 + off-axis guiding camera...) about 
6
pounds and in order to avoid the focuser to slip, I tightened the 
focuser
and found out that the pressure is applied on two little bearings with 
two
little screws... now since the pressure is not spread on the bearing, 
what
had to occure did... and the bearing racetrack broke in pieces... I 
took it
appart and fixed it, but I was not really impressed by that part of the
design, looks like someone could do much better.

Also, the JMI will have quite a bit of slop with that kind of load.

                -- Benoit