Re: the focuser–if the chapstick stiffens up at just 58 degrees (and nights are going to get a LOT colder than that for the two of us) I’m wondering if the teflon tape route might be the better option for late Fall, Winter, and early Spring with chapstick the choice for warmer months.
Use wheel bearing grease. I put it on my focuser 3 or 4 years ago, and it still works great at all temperatures.
Hi Pauly.,plumbers tape will shred with use.,I’m wondering if anything will be needed in winter.,things tend to contract in the cold.,may make for a tighter fit.,I’m going to remove most of the chap stick and see how it goes.,I trust what Steve says about bearing grease,,I just don’t trust myself to keep my fingers out of it.,I have had to wipe chap stick off on my sleeve more then once.,,
Whoever thought up the idea of using Chap-Stick lip balm on the focuser threads on the OneSky is a genious. I did that today and what an improvement that was! Smooth as silk and no thread slop at all.
The helical focuser on my unit was very loose. It was so loose that the collimation would change with every turn of the focuser. This is a common problem that folks remedy with Teflon plumber’s tape or grease or Chapstick. These never worked for me. The plumber’s tape always disintegrated after a couple uses, and the grease didn’t tighten up the “slop” sufficiently and would get squeezed out, plus I would always get grease on my fingers or gloves.
Here is a new idea that fixed the problem for me. Radial compression!
Wrap a layer of rubber around the outside of the focuser. I had the perfect item on hand, but I think a couple layers of bicycle inner tube would work too. Then use a worm-gear hose clamp to compress the focuser. Tighten the clamp gradually checking to make sure the focuser will still turn easily. Make the clamp as tight possible without making the focuser too difficult to turn.
I didn’t mention the “focus handle”. I swapped the stock grub screws for longer ones I got from ScopeStuff (thread size M4). I needed the extra leverage to turn the focuser in cold weather when the grease was very stiff. I covered the exposed threads with some clear plastic tubing (left-over from another project) just to make it more comfortable to push on.