Re: ATM Tangent arm drive

["Don Clement" <clement.focuser@verizon.net>]

Hello Tom,


> Has anyone made a tangent arm nut that is functionally similar, but uses
> compliant hinges instead of sliding components?  I would be interested in
> any info on such a compliant hinge design...photos, etc.

> Compliant hinges, when implemented properly, have practically zero
> backlash, and can have high stiffness in the 'non pivoting' directions.



Check out the compliant pivot used to support the worm against a worm gear
illustrated by Porter in the ATM books. I believe it was in the section on
Springfield mounts.

I used compliant hinges for a guide scope positioner  that would could be
applied to tangent arm. Look in the ATM archives for messages postedabout a
compliant guide scope positioner.  I might suggest that solid compliant
hinge be machined from a solid block (aluminum) that the nut is attached to.
This would make for a design with minimum of parts. In addition,  the nut
could be machined from Turcite X, a self lubricating plastic. No lubrication
would be required for a tangent arm using a  compliant hinge and Turcite X
nut.



Don Clement

Running Springs, California

http://www.clementfocuser.com