Orion Atlas /EQ6 pier/mount extension
Posted 07 June 2009 - 09:19 AM
I bought one used off astromart and the original owner never took it out of the box. The pier came with some bolts and things shipped inside of the hollow column.
Fred1 came over and made sure I had it on correctly, but there was a two piece ball bearing race (i think that's the term) that I just put in between the mount and the pier I think.
As hard as I tighten the original lock under the trpod hub, there is still consderable movement in azimuth I guess due to the pier not being tightened down enough?
Posted 07 June 2009 - 10:36 AM
This is a "known issue". I simply tighten mine as tight as I can by hand (so that I can also remove it by hand later). Some folks have actually used adhesives to fix (temporarily) the pier extension to the tripod. Another fix has been to cut a hole in the underside of the pier extension and install a stopper pin (like the one you transplant from the tripod to the top of the pier extension).
With a little extra care and "oomph" mine rarely loosens during use, but it does happen. I would probably try one of the other fixes but I plan on moving my Atlas head to my Antares pier shortly and won't need an extension.
Posted 07 June 2009 - 07:10 PM
Orion (or Synta) saved some money on this little pier by not putting an azimuth pin on it. You must rely on friction to keep the mount (and scope) from slipping. It's not a good idea, IMHO.
That thrust bearing goes on the bolt that holds the mount to the extension. It allows you to tighten the bolt, yet still allow movement for polar alignment. The thrust bearing goes on the bolt, then the bolt goes through the pier top and holds the mount. (Then you can bolt the extension together after that.)
When I had my Atlas, I drilled the bottom plate of the extension for an azimuth pin. The pins are 10mm, IIRC, and you can just cut off the threaded portion of a bolt. It doesn't have to be fancy. Trust me, anything is better than friction.
Hope this helps,
Posted 08 June 2009 - 08:57 AM