Skywatcher 12"

[Cate]

Hi everyone, 

I've had a long break from stargazing, the last entry in my journal was 2010. Very embarrassing. Having kids seems to have been the biggest culprit there. There are so many things I've forgotten. I'll probably be asking a lot of questions for a while! 

I got out and looked at jupiter tonight which was fantastic. The conditions tonight were awful so I didn't get to see anything else, no moon but a neighbour's flood light and intermittent clouds were my enemies. 

Just with the scope though - the dobsonian mount is a bit sticky. It always was, but I wondered if this is normal or whether it should move like butter in all directions at all times? Can I make it any smoother? And how do I do this as the mechanism is obviously hidden in the mount. 

And secondly the three poles which extend up and collapse down have become very stiff, there were always very smooth. I'm guessing just age and being out in the open air (stored inside) has made any lubrication disappear. What can I use, if anything, to loosen these up a bit? 

Thanks, cate. 

[Jimtheslim]

Depends what the poles and fixings are made of. If they're plastic then I don't see why a well aimed and controlled quirt of dry silicone wouldn't help. If It's metal then maybe a bit of WD40.

I have the 10" solid tube and I find the base a bit sticky sometimes, in that when I go to nudge it resists slightly, then springs round a few millimetres causing massive sways in the eyepiece. I loosened the nut on mine ever so slightly and put some WD40 in and it was a lot better

[Louis D]

You want a little bit of "stiction" so the Dob will hold its position when you let go of it.  Creating that perfect balance between too slick and too sticky is the real trick to having a good Dob mount.

[Cate]

Thanks. 

That's exactly what I get jimtheslim. In the 10mm eyepiece I have to be really careful not to lose what I'm looking at. I have to really pull it far too much with a well timed push back to get it just move a tiny bit. 

Where do I find the right nut to loosen? Sorry basic question. 

[Jimtheslim]

I'm sure mine was just the main bolt that just goes through the centre of the base. If I remember correctly there is a plastic collar on which it spins so i think I recall taking it apart and putting a little silicone on the plastic parts and not doing it all up so tightly

[lnlarxg]

Put in a lazy Susan bearing, you can get one on amazon.

i installed the lazy susan on my 8” dob and was overjoyed by the smoothness, though bit too smooth so I cut strips of old carpets and wedged them in between the dob base gap for sticktion 

It worked so well I was very proud for 2 days