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Would this work for a dovetail saddle?

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#1 thinger62

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Posted 13 March 2010 - 10:25 AM

I've got a used Super Polaris mount coming. I plan on putting an Orion 120mm ST refractor on it. I also have a Nexstar 8se, and it occurred to me it might be nice to mount that on the same polaris occasionally (I believe it will handle an 8" sct). So naturally, instead of bolting rings, now I'm thinking dovetail. I know ADM has a combination saddle and mount head for the polaris, but that's $110. Since I already have (or will soon, fingers crossed) the head, all I need is the saddle. The super polaris head has 2 mounting tabs for 1/4"x20 bolts, I believe. The thought of just using one of these tabs kind of makes me nervous. Apparently broken tabs are not that uncommon. So, and here's the question. Is there any reason why I couldn't use 2 of these little adapters, one on each tab? It would save me at least $60...and while not a lot, if it work, why not?

http://www.telescope...=pjn&subid=3578

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#2 jason_milani

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Posted 13 March 2010 - 01:21 PM

They will work as long as that plate is flush accross the top. You may want to have a look at this: http://www.admaccess...s_SP_Saddle.htm instead. a little more expensive but a much more secure option.

#3 Jim7728

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Posted 13 March 2010 - 01:25 PM

Should work. I have one I'am going to use to attach a small cw beneath a vixen dovetail bar. I did have to remove the plastic sleeve on the T bolt in order for it to slip over the bar.

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#4 vinnie

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Posted 13 March 2010 - 05:19 PM

This one might be OK

http://www.optcorp.c...-12611&kw=&st=0

#5 vinnie

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Posted 13 March 2010 - 06:08 PM

And here's a genuine vixen saddle

http://www.optcorp.c...-11303&kw=&st=0

#6 StarStuff1

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Posted 13 March 2010 - 06:21 PM

You can pretty easily make your own dovetail out of a good hardwood (like red oak) and some aluminum strips. I would use at least 3/16-in thick aluminum for a C-8 size scope, I made a dovetail plate that switches between the alt-az mount shown here and my Super Polaris mount. BTW, the SP mount will handle your scopes. I have routinely used a ST 120, a 127f/6.5 and an 8-in f/4 homebrew newt. A factory rep told me years ago that the max capacity of the SP is around 25 lbs with a very short tubed scope like a S/C.

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#7 StarStuff1

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Posted 13 March 2010 - 06:23 PM

Forgot to add that I drilled two holes and installed T-nuts in the dovetail after this pic was taken. 1/4x20 thumbscrew go right through ths SP head plate to the dovetail.

The SP mount is a good one.

#8 thinger62

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Posted 13 March 2010 - 08:39 PM

I found both of the dovetail saddles mentioned above. The only problem is, I'd have to mount one of those on just one of the tabs of my mount head. That makes me nervous. There is no center mounting hole on the SP mount head, as far as I know.

#9 vinnie

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Posted 13 March 2010 - 09:09 PM

I found both of the dovetail saddles mentioned above. The only problem is, I'd have to mount one of those on just one of the tabs of my mount head. That makes me nervous. There is no center mounting hole on the SP mount head, as far as I know.


No you would bolt an aluminium plate to the two existing lugs then fix the saddle to that plate with two or more screws. I guess it depends on how handy you are, but its not hard to cut a piece of aluminium bar and drill a couple of holes in it. I just thought that OPTs saddle at $39 was a cheap way out.

#10 thinger62

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Posted 13 March 2010 - 09:45 PM

Yes, that makes a lot of sense. That's why I like this place:)

#11 vinnie

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Posted 13 March 2010 - 10:01 PM

Oh and just to give you a sense of scale, the genuine Vixen saddle is 80mm diameter, so I would imagine the OPT copy would be a similar size. That's also about the same size as the standard saddle on most small mounts, like EQ3, EQ5, GP2 etc so there is more than adequate area to carry the scopes you propose






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