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Atlas and Stiction for Alt/Az adjustment

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#1 Madratter

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Posted 01 June 2013 - 04:12 PM

I got my new Atlas, and overall I'm very pleased. See my post in the beginner intermediate imaging for my impressions.

However, there is one area that isn't so great, and I don't know what is normal and what isn't for this mount.

In particular there is a great deal of stiction in both the alt and azimuth settings. This is particularly true with azimuth. I'm used to my CG-5 where those knobs move the mount head quite easily, even with my telescope on it.

That is not the case with my Atlas. In fact, I have to untighten the knob below the stand that holds the mount to the tripod to get it to move at all.

And I seem to have maxed out the travel in the one direction even though the knob is no where near the end of travel.

Any hints from those who have dealt with this?

BTW, they seem to have changed the size of these adjustment bolts. I keep reading how they are the same as on the CG-5 but on mine they are quite a bit larger and beefier. They just aren't working well.

#2 rmollise

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Posted 01 June 2013 - 04:18 PM

Yes.

What's worked well for me for the last five years is a thin layer of bicycle chain grease on the azimuth interface between mount and tripod. Don't tighten the central rod down completely until you are done polar aligning.

The altitude? Even simpler. If I need to raise it, and I have counterweights and scope mounted, I just give it a little help by pushing up on the counterweight bar as I crank it up. Be sure the forward bolt is loose. It is only for locking when you are done.

Usually you don't have to move far in either direction and "simple" is usually best. ;)

#3 Phil Sherman

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Posted 01 June 2013 - 05:40 PM

If you look at the tripod for your Atlas, you'll see that there's a raised ring around the edge that's about 10mm wide and 0.5mm high. This is the bearing surface that the mount rotates against when you're adjusting it in azimuth. If you've properly tightened the bolt that attaches the spreader and tripod to the mount, it's almost impossible to adjust the mount in azimuth. You'll need to slightly loosen the mount end of the bolt first. The altitude adjustment bolts should be checked with no counterweights or scope mounted. If adjustments are still too stiff, you need to change the tension adjustment for the altitude bolts. Unfortunately, that adjustment is buried under the glude on plastic "Orion Atlas" plastic caps and it's difficult to remove them without damage.

I replaced the South adjustment blot, the one that lifts the counterweights, with a stainless steel bolt. This will prevent bending the bolt when adjusting it with a full load on the mount. Not everyone ends up bending the bolt but I wanted to make sure I didn't bend mine sometime when I'm on a field trip.

I also went to a local hobby store and picked up a sheet of high density polyproplene which was cut into a ring that was glued to the tripod and makes a smooth bearing surface for the mount to ride on.

Phil

#4 Madratter

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Posted 02 June 2013 - 07:25 AM

Well, at least this is common and my mount isn't a lemon. I ended up getting some lithium grease and applying it. That worked well with the telescope not mounted using the polar alignment scope. I'll keep the polyproplene in mind if it doesn't work well enough with the scope actually mounted.

#5 gonzosc1

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Posted 02 June 2013 - 07:57 AM

don't know about the new atlas, but the standard manual says to loosen the lower knob for setup then tighten afterwards..

#6 FaronD

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Posted 02 June 2013 - 09:09 AM

I used grease on both of my EQ6's, that fixed the stiction in azimuth adjustments. As Phil already mentioned, to make adjustments on the alt, the plastic cap, which is glued, will have to be gently removed to access the grub bolts underneath. I've always found the gotos to be spot on when using EQmod, just make sure you select at least 3 stars in 3 different quadrants.

Faron






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