Dobsonian main base movement improvements.

[Grump Martian]

I have a Skywatcher 250 mm flexitube Dobsonian. I would like to improve the rotation movement on the base. Currently there are teflon pads. I am interested in what other owners have done to achieve this. Thanks.

[Ricochet]

I bought enough of these in various thicknesses to make a stack so that the base was just floating off the Teflon pads and then tightened the central nut to pull it back down and get the required friction. I think I probably went for the maximum 80mm outer diameter and then a central hole to match the size of the connecting bolt. 

Teflon/PTFE disc

[apaulo]

i have fitted lazy susan bearings on a couple of dobs with very good success. then put a bolt through the middle to add the friction required. the last dob i fitted out was a 12" f6.5. no problems.

[Mr Spock]

This was my solution for the 12"

[John]

I have recently acquired an 8 inch Skywatcher dob (solid tube) and needed to make similar improvements to the azimuth motion.

After a few experiments I found adding a single "milk carton" washer between the stock teflon washer and the bottom board worked quite well. It takes some of the weight of the scope off the teflon pads but is still stable. Some folks find that they need more than one such washer but in my case, one worked just fine.

I cut the washer from this type of milk carton. Another tip is to remove the milk before cutting the washer 😁

[IB20]

I asked FLO about these roller bearing bases for the 200P and they said there’s no reason it shouldn’t work. https://www.firstlightoptics.com/misc/stellalyra-roller-bearing-for-dobsonian-telescopes-8-to-16-aperture.html

Edited November 10, 2023 by IB20

[Mr Spock]

They are ok for smaller scopes, but that's the same type as supplied with my 12". It was hopelessly inadequate.

[cajen2]

But as you suggest, superb on the 8".

[Ratlet]

On 10/11/2023 at 18:59, IB20 said:

I asked FLO about these roller bearing bases for the 200P and they said there’s no reason it shouldn’t work. https://www.firstlightoptics.com/misc/stellalyra-roller-bearing-for-dobsonian-telescopes-8-to-16-aperture.html

I have the 10" Stellalyra which came with one of those.  I found it worked pretty well but sometimes you'd hit an unstable bit in the roll.  It was like you were perched at the top of a hill and the bearing would try to roll off.  Made lining up on a target intensely frustrating.  I went for a lazy Susan bearing from eBay (18")

https://www.ebay.co.uk/itm/141742604866?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=v12QWvjJSAG&sssrc=4429486&ssuid=PvuSuZhdTlO&var=&widget_ver=artemis&media=COPY

And it it smooth all the way.  I threw a teflon pad in the middle by the central locking nut to give it a bit of friction.  Works like a dream.