RE: [ATM] Dob Design Questions

["lou krajci" <loukrajci@comcast.net>]

>From: "Jan and Rod Shea" <jnrshea@comcast.net>

>How should I decide what radius rocker bearings I should make, and where
should I put the CofG?...

When calculating CofG with a spreadsheet...don't forget about
non-symmetrical or odd shaped or oddly located parts, such as 'half-moon'
shaped elevation disks, etc.  They will shift the CofG of the entire scope
in an unusual manner because their individual CofG is not centered with
respect to the center of your telescope tube.

If I remember right, for a solid 'half-moon' disk...the CofG lies approx
0.42 of the radius from the center toward the edge.

I hope this helps.

Tom Krajci
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