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Orion Mount Extension?

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#1 CollinofAlabama



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Posted 11 August 2014 - 06:39 PM



I'm a bit frustrated.  I find my optically excellent C102GT awfully difficult for zenith targets.  I use the Synta AZ-4 mount head on a set of Hands On Optics wooden legs with solid metal eyepiece tray to provide a relatively steady setup, but zenith targets, besides being very uncomfortable, are sometimes simply impossible, as my focuser can smack up against the legs, prohibiting views at zenith.  I have replaced the focuser with a Synta single speed Crayford (from an Orion 100ED?), which is a big improvement over the adequate, if greasy, Synta standard rack & pinion it came with.  This focuser is light weight and relatively small for a Crayford, which suits me fine, since I don't use eyepieces over a pound, can't use binoviewers, and am not into AP at all.  So for my needs, the focuser is the cat's meow for an optically excellent performer.


But, there's the zenith problem.  It's bothered me so, I've even considered replacing it with a 150XLT 6" reflector.  But Don Pensack noted I might have the same problem, and this has been confirmed by Eric63.  So this makes the Orion Mount Extension more compelling.  First, although I believe it is, can someone confirm it would work with the Synta AZ-4?  I wrote Orion and was told, no, it only works with the SVP.  Uh, I've read extensively here -- and even on Orion's own reviews section for this product! -- that it should work with the EQ-3/AZ-4 class of mounts, but I thought I'd ask to make sure.  Assuming it is true, does anyone know how much it weighs?  Also, is there something else available that might be lighter and a bit smaller.  I'm betting an 8" extension would be enough.  16" will certainly make zenith targets "get-able" with my C102GT, but skiing behind a Battleship wasn't on my agenda.  To say nothing of the weight of this bad boy. I'm sure it's solid, but I was hoping for something a little more, hmm, practical.  Like an 8" extension, which should clear my focuser-leg issue, and hopefully not make this mount so heavy and unwieldy I don't want to use it.


Any advice is appreciated.

#2 Max Power

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Posted 11 August 2014 - 09:31 PM

Orion has another extension column for their bigger mounts, forget the name, but it uses 12mm bolts and is only 9" tall.

My tripod and mount head uses 8mm bolts.  They slip right through the mounting holes.  Went to the hardware store and 

added nuts and big flat washers to secure it all together, works great!

#3 stevew


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Posted 11 August 2014 - 09:55 PM

I know you are asking a question about a mount for your refractor, but you will probably get more a detailed response by asking in the "mounts" forum 



#4 SteveG


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Posted 12 August 2014 - 12:54 PM

That pier extension is really heavy - sorry don't have the weight handy. I recommend taking it to a machine shop and have them it cut down.


First confirm it fits your mount. I was able to fit one to a Vixen SP mount but I had to grind down the stub on the tripod hub a bit.

#5 AlBoning


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Posted 17 August 2014 - 09:37 PM

I get 11.25 lb, so call it five kilos.


I also have the Atlas pier extension.  As the piers are identical, except for length, and the mounting hardware is interchangeable one can use either pier on either mount as circumstances dictate.

#6 k5apl


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Posted 21 August 2014 - 12:42 PM

I bought the extension for the SVP mount from Orion, and use it on my CG5ASGT.  I had a machine shop cut it into tow different length pieces (smaller one

was 4 inches per my spec).  So now I have two extensions that work with different telescope lengths.  Sorry I cannot answer your original question, but offer the suggestion of having a specific length cut for your application.



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