Re: Re: Is this too nuts to consider ?

On 25 Jan, CAD_CAM_EDM_DRO@egroups.com wrote:

>
> Personally, I think it would be much simpler, quicker and lots cheaper to
> simply use a differnt gear ratio on one of the compound gears between the
> spindle and the gearbox.

It would be, if I could find suitable gears. Unfortunately, I can't.

The manufacturer sells a pair of gears that gets things down to 4TPI
with the stock leadscrew - with my fancy ballscrews, that means 8 TPI.

What I want is ONE TPI.

I'm making a focuser for a Newtonian telescope .. a tube inside a
tube, basically. I plan to cut the coarse thread on the outside of
the inner tube. The outer tube will have a single small diameter ball
spring loaded, pressing into the thread.

Alan


--

Alan Rothenbush | The Spartans do not ask the number of the
Academic Computing Services | enemy, only where they are.
Simon Fraser University |
Burnaby, B.C., Canada | Agix of Sparta