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Dobsonian mount for 8inch telescope?

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#1 Metalmanstan

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Posted 07 August 2012 - 10:07 PM

I recently just pruchased an old telescope from my buddy for a small amount of cash. It is an 8 inch Edmund scientific. I also have a Orion 4.5 skyquest. I love the dobsonian mount for the 4.5. The 8ich has a cast iron mount (which is about 70lbs total!!) And its very tough to maneuver around. So I was wondering if there is any place to get a dobsonian mount for the 8inch scope or any mount that's not steel and is easily portable. Any information helps. Thanks!!! :smirk:

#2 gnowellsct

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Posted 07 August 2012 - 10:57 PM

Hmmm. Not so easy. Best bet is to join a club and have someone help you build one. I have seen in the field a decent fold up wooden mount, carrying a six or eight inch; but even though it was nice I considered it outlandishly priced at around $1k. That was just the base, not the optics. I think the vendor was advertising in the back of S&T but I don't remember the name.

Your Edmund 8 is probably f/6 so the simple solution of buying an Orion XT8 and selling the tube and mirror and keeping the parts you need to add the Edmund probably won't work.

Porting an older tube like this into a dobson format is done fairly often, but don't go on to classic telescopes if your heart is set on this, because they will urge you to restore to good condition.

The other option would be to sell the whole thing to someone who wants an old telescope design and use the funds to buy an 8" dob. BUT, your 8" Edmund likely has better optics than many, though not all, of the Chinese dobs on the market.

Greg N

Greg N

#3 Mirzam

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Posted 08 August 2012 - 04:38 AM

You can build a dobsonian mount that holds the tube without any modifications. Then the "classic" aspect can be recovered if needed.

JimC

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#4 Metalmanstan

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Posted 08 August 2012 - 11:31 AM

Is there another alternative to the cast iron mount? That thing is a pa in to haul around!! Not to costly thou

#5 Husbyggarn

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Posted 08 August 2012 - 03:41 PM

Any mount that should hold a 8" F6 steady is going to be massive = $$$. Except for the dob mount that can hold much larger scopes steady and not cost a fortune.
You can build it yourself with basic power tools.
Why don't you head on over to the ATM section, for more ideas and help.
Good luck!

#6 ckwastro

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Posted 09 August 2012 - 02:46 PM

Dennis at Dob Stuff is making custom rockers now. My guess is he could make you some altitude bearings as well.

Dob Stuff Custom Rockers

#7 gnowellsct

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Posted 09 August 2012 - 10:47 PM

Any mount that should hold a 8" F6 steady is going to be massive = $$$. Except for the dob mount that can hold much larger scopes steady and not cost a fortune.


Modern GEMs capable of holding a tube like this are not so massive. The old mounts were *certainly* massive and also not that effective at being stable.

Stepper version G11s sometimes sell as low as $1100.

The cost effectiveness depends on whether OP already has, or has access to, the required power tools. If he has to buy tools the cost goes up, but of course he then has the tools for the rest of his life.

GN






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