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CG-5 GT mount axes tension difference

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#1 ibase

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Posted 16 May 2009 - 11:04 PM

Hi all,

Being quite new to owning a new CG-5 GT mount, I noticed that when the two clutch knobs are loosened up, it is easier to manually rotate the head in RA than it is on Declination. Is this difference in tension between the two normal or should they be identical? Can/should I make adjustments on the Declination to loosen up the tension a bit so that it is identical as the tension on the RA? Thanks in advance for any response. Clear skies to eveyone.

Best,

#2 AlanT

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Posted 17 May 2009 - 09:40 AM

In my opinion, the DEC being a just a little stiffer is normal. There are a couple reasons. One is that it just feels like that because your turning less mass/momentum, the second is that the RA axes has bearings, the DEC does not.

The resistance in the DEC axis can be affected by a number of things, but there is only one external adjustment, which is the the thrust clearance. If that's too tight, it will make the axis stiffer. I've even heard of a case where the set-screws that secure the thrust collar were loose and during use the collar tightened enough to cause further damage to the mount. You can get the details of how to check and set the thrust on the astronomyboy website (http://astronomyboy.com/cg5/).

Other things that may affect the resistance is the type and amount of grease used around the worm wheel, the worm wheel shim set up, the weight on the mount (remember, no bearings), etc. However, to work on these things your involves a teardown and reassembly of the mount, refer again to the astronomyboy site.

Hope this rambling helps,
al

#3 ibase

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Posted 17 May 2009 - 10:58 AM

Al, thanks so much for your response; I will read up on the website you pointed to ascertain if all is well with the mount; in the meantime I will refrain first from further using it. Thanks again.

Best,

#4 rmollise

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Posted 17 May 2009 - 01:07 PM

Hi all,

Being quite new to owning a new CG-5 GT mount, I noticed that when the two clutch knobs are loosened up, it is easier to manually rotate the head in RA than it is on Declination. Is this difference in tension between the two normal or should they be identical? Can/should I make adjustments on the Declination to loosen up the tension a bit so that it is identical as the tension on the RA? Thanks in advance for any response. Clear skies to eveyone.

Best,


Normal for the mount. Nope. You want the two axes both locked firmly when in use or your go-tos ain't gonna go-to worth a squat.

;)

#5 ibase

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Posted 17 May 2009 - 08:10 PM

Thanks Unk Rod! I was kinda hoping that you'd say that, that it's just normal. Ok, I'll make sure the two axes are both locked firmly.

Best,






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