Question on Dobsonian altitude bearing size

[JamieQ]

Hey everyone, 

I'm looking into the design of Dobsonian mounts. A variable I can find little information on is the size of the altitude bearing, and how an appropriate size should be chosen for a given mirror size (or more appropriate for my application, a given weight).

To be clear, by altitude bearing I am referring to the arc shaped component which sits upon the base, as shown in the image below.

If someone has some insight on this I'd be truly grateful!

(Image from here)

Edited February 7, 2022 by JamieQ

[johninderby]

I think the bigger the better more or less but this article gives the calculations to work it out.

http://atm.udjat.nl/articles/Dobson Slide Bearings.pdf

Edited February 7, 2022 by johninderby

[johninderby]

Found the article on calculating the size of the alt bearing and added it to my earlier post.

[JamieQ]

12 hours ago, johninderby said:

I think the bigger the better more or less but this article gives the calculations to work it out.

http://atm.udjat.nl/articles/Dobson Slide Bearings.pdf

This is exactly what I needed, thank you! 

[fwm891]

At one time the OD of the primary was a good basis to start from