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Atlas/EQ6 altitude adjustment upgrade

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#1 snelltaylor

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Posted 09 February 2011 - 09:40 PM

When polar aligning, I've been fighting with the altitude adjustment screws on my Atlas. The problem stems from the fact that the head is cast aluminum, where the bolts are steel. The threads are already pretty loose, so at higher torques the aluminum tends to gall and make it hard to move the screw. It makes fine adjustment impossible, and is just getting worse. I'd talk to Orion about warranty and replacement, but the problem would be the same with a new one.

So, my solution is to drill out the threads, get threaded steel inserts and put them into the casting with a jam nut so they won't turn. That way, all the friction of adjustment in the future is steel against steel, and there shouldn't be any wear problems.

Thoughts, comments, suggestions?

#2 Doug76

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Posted 09 February 2011 - 10:03 PM

I help mine by pushing against the mount head, essentially lifting it when adjusting the altitude. That prevents the problem you noted, and makes adjusting easy.

#3 ch2co

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Posted 09 February 2011 - 10:54 PM

Aah, the weakest point of the Atlas mount. Your idea to add steel (I'd suggest stainless steel if you go ahead with it) sounds good. I would suggest going to a larger size bolt, (also stainless steel) probably socket head (Allen) bolts would be great. Then get a T-handle Allen wrench to adjust the altitude, which gets the stupid dangling arms out of the equation. The insert could be locked into the aluminum blocks with Locktite avoiding the need for a lock nut. Regardless whether or not you go ahead with this operation, the biggest thing that you can do is to lubricate both the threads and the point of contact for the bolt ends. Superlube is great. You might also check with Ed at Deep Space Products for advice, he does a lot to upgrade these mounts and could provide sage advice. And finally, join the EQ6 group at the Yahoo EQ6 Groups site. That's the only thing that that they talk about. You might just try the lubrication along with the above suggestion to lift the head while adjusting, and don't do major adjustment with a full load on the mount. Good luck from a fellow EQ6 owner.

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#4 Planemo

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Posted 09 February 2011 - 11:11 PM

When polar aligning, I've been fighting with the altitude adjustment screws on my Atlas. The problem stems from the fact that the head is cast aluminum, where the bolts are steel. The threads are already pretty loose, so at higher torques the aluminum tends to gall and make it hard to move the screw. It makes fine adjustment impossible, and is just getting worse. I'd talk to Orion about warranty and replacement, but the problem would be the same with a new one.

So, my solution is to drill out the threads, get threaded steel inserts and put them into the casting with a jam nut so they won't turn. That way, all the friction of adjustment in the future is steel against steel, and there shouldn't be any wear problems.

Thoughts, comments, suggestions?


A simple heli-coil should fix your problem, they are made from stainless steel and should last forever.

Before I bought my Atlas I thought the adjustment screws would need replacement right away by all the bad stuff I read about them, one thing I did do is back the adjustment screws back a long way and I noticed the head was really tight and would barely move, so I kept working it back and forth by hand until it felt like it moved much easier, I think it had some dried paint in the joint and maybe a few burrs left over from machining, after doing that the stock adjustment screws work just fine, at least without a heavy scope mounted on it.

#5 snelltaylor

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Posted 10 February 2011 - 03:32 AM

Thanks for the thoughts. I was planning on using stainless, and yes, basically a helicoil. The jam nut was only to ensure the thing wouldn't move, and to take any sort of play out of the outer threads, loctite would probably do the same. The threads are lubed, but enough aluminum is gone that it's just not happy when making adjustments while loaded and with tension on the screws already. I ran a tap through the threads and re-lubed, we'll see if that makes a difference. I was trying to keep the stock screws just to keep from having to have any tools, but a longer moment arm would be nice, not to mention the fact that the stock screws are a little bent. They're just machined nicely with the round tip on the end with no threads...
I was also thinking about acme screws just for something designed to take the force and wear, but that's a whole other can of worms for tools, cutting, machining, etc.

#6 alpal

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Posted 10 February 2011 - 05:43 AM

It is a problem.
I find myself having to use long vice grip pliers
to be able to turn the adjustment screws.
It is a very bad design.

I might put on some thick lithium grease & see if that helps.

I am still waiting for a good night to check out my
new guiding system properly after my mount was tuned up.
It might be the case that a slight Dec offset is required to have good guiding.
i.e. PHD guiding turned off in one direction.

e.g. if the star heads North, switch North off & only
adjust Dec in South to avoid any backlash.
I will find out soon enough.

#7 Asimov

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Posted 10 February 2011 - 06:02 AM

I greased my bolts from brand new. Haven't had a reason to bother with the upgrade yet.






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