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Gibraltar mount + 4" Mak ?

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#1 Chassetter

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Posted 23 June 2013 - 10:31 AM

Hello,
Thinking of mounting a Nexstar 4 SE I have en route (avec Kendrick dewcap ) to my Gibraltar mount for visual use. Would such a setup cause COG balance problems if it is balanced for 60 degrees in altitude? Most objects I view are above 40 degrees to get out of the soup.

I reason it would be extremely stable for such a short ota and weight load as I could use it fully collapsed from a seated position with vibration pads.

OTA weight 3kg (~7 lbs with dewcap and 32 mmm plossl) The listed online OTA weight from Celestron seems to be the OTA+Mount head and controller.

OTA length is 13.5" sans dewcap.

I would order a vixen dovetail shoe from scopestuff:
http://www.scopestuff.com/ss_ds13.htm

The dovetail on the ota will need to be moved 90 deg. as it is situated for a side-saddle setup .

Would a side-saddle mountbe a superior setup balance wise any way for a short tube?

If so, does anyone know of one that fits the Gibraltar's tripod hub or accept the Gibraltar's tripod legs at it's own hub?

Any input much appreciated! :jump:

#2 Chassetter

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Posted 24 June 2013 - 09:17 PM

Anyone? :tonofbricks:

#3 Jim7728

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Posted 25 June 2013 - 05:31 AM

The 4" Mak on the Gibraltar should work fine. You may have some trouble attaching the Scope Stuff dovetail saddle to the Gibraltar cradle as the holes don't quite line up, but think I did it with smaller screws. Also be aware there may not be enough clearance for the saddle knob to rotate. I recall using a Baader viven saddle which had a smaller diameter knob.

Maybe consider using tube rings with the Vixen dovetail rather than epoxy.

I think the Porta II saddle is on the wrong side for the Mak dovetail.

Gotta go to work, hope that helps.

#4 Chassetter

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Posted 25 June 2013 - 08:11 AM

Thanks for the input Jim. I ordered the dovetail shoe from scope stuff, waiting on delivery. I have seen photos pf it attached to a gibraltar head, but yes the saddle knob on it was replaced with a bolt, should turn by ratchet. Biggest concern is the ota balance when changing altitude on a cantilevered cradle setup like this. Nothing that time and money can't answer for it I suppose.






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