Dob Mount & Bearings

[duncan]

Hi All,
Well i've had my scope for a week and the only problem i've had is sticky azimuth motion. Had a look at the mods in projects and articles and applied same. Didn't make a lot of difference even with graphite powder. So i'm getting hold of a few brackets and mounting some bearings into the base. Should still be able to get enough tension to make it steady. I'll let you all know in about a week. As for the viewing here tonight it's lousy. But i'm hoping the cloud will clear by 2-3am. Gotta get some decent eyepieces too!!!
Cheers,
Duncan

[iceman (Mike)]

Hey Duncan.

I know most 12" owners have gotten great results using ebony star laminate in-between the two bearing surfaces for smoother azimuth motion. The 12" is probably too heavy for the other modifications (milk bottle washers) etc to work as effectively as it does on the lighter scopes.

[duncan]

Hi Mike,
I think you might be right about the weight issue. I tried the milk bottle washers and i tried using leather with graphite powder as well (fishermans drag washers). I'll have a go with the bearing idea and let you know how i go.
Cheers,
Duncan

[davewaldo]

I did the ebony star laminate upgrade on my dob this week and its amazing the difference it makes! I'm still using the stock teflon but now the scope moves soooo smooooth!

Where before I had to bump and nudge my scope to move small amounts I can now just apply a small amount of pressure and the scope movies very slowly and smoothly. NICE!

I also have a portion of laminate left over which I would be happy to sell and would be enough for most dobs. PM me if your interested.

[erick (Eric)]

That's good news, Dave. I'm excited at the prospect! I have my piece of laminate in the shed ready to do the task. Just waiting on new teflon and a central pivot bearing from the US. Bought the contact cement last night! Going to have a go at the Alt bearings as well - I have some ideas for an easy approach.

(ps. I read one report that said that rippled laminate wouldn't work because the teflon would deform into the ridges and valleys while it was stationary and you'd have to push it "up hill" to start the movement!! That person is in the minority of one, so I've decided to ignore them )

[rmcpb (Rob)]

If you are going to play with the alt bearings consider making them larger to improve the movement AND balance issues.

[erick (Eric)]

Originally Posted by rmcpb

If you are going to play with the alt bearings consider making them larger to improve the movement AND balance issues.

That's a bit more than "playing" with them

But your base ideas look very tempting:-

http://www.iceinspace.com.au/forum/s...ad.php?t=14420

Perhaps a future development for me?

Thanks Rob.

Eric

[Starkler (Geoff)]

I use a combination of bumpy laminate (cheap ebony star substitute), paste car wax and milk bottle washers and it moves like a dream