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Re: ATM: fork mount




"david s. white" wrote:
> 
> Help,  I've made the fork for my 8/f7 newtonian but unfortunately the arms are both
> tilted very slightly to the left, ~ 1/8th of an inch or slightly >, at the distal ends 
>of the arms.
> I'm too personally involved with this project to think rationale on the subject.  The 
>arms
> extend about 20 inches out and the declination bearings at 17.  Would I be better of
> adding a disk, ie. split ring mount, at the ends of the arms to try to "pull" the arms 
>into a
> more parallel position (or am I merely chasing my tail)?  The fork is made of oak, 3 1/2
> inches thick by 2 1/2 inches.  Any input would be appreciated,  I can't find anything 
>in the
> archives.  Thanks.  David White
Hi:
As long as the Dec/Alt axis is perpendicular to the RA/AZ axis there should 
be no problem, you can check this by fixing an pointer external of the assmby
to point at a place on the Dec/Alt, axis then rotating the RA/AZ axis 180d and
see if the pointer is pointing to the same place on the opposite arm of the
Dec/Alt axis. If everything was the same measurement when you assembled you
may have gotten just a parallelogram type shift, if not, just shim it to bring
Dec/Alt axis parallel to the plane of Ra/Az rotation and if there is enough 
room for the OTA to pass through the forks and it is not grossly off enough to 
be not pleasing it don't matter, 1/8 doesn't sound like much.
-- 
Aloha   159 30 W, 21 55 N
Brian   Middle of the Pacific,
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