Crayford construction
Mitch Berkson (mitchb@world.std.com)
Mon, 1 May 1995 10:06:14 +0059 (EDT)
I recently looked up an old S&T article on the Crayford focuser. It
seems straightforward, but I have a question about the JMI
implementation. In the JMI focusers in which ball bearings are used for
the focusing rod, how is the tension provided to prevent the draw tube
and eyepiece from slipping?
The drawings I saw had simple metal bearings which pressed against the rod
with a spring to provide this force. Thanks.
Mitch