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Pathetic CG-5 latitude adjustment bolts

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#51 RTLR 12

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Posted 27 June 2013 - 01:16 PM

Shane,

How about metric grade 10.9? That's the metric equivalent to grade 8 std. It's only nomenclature.

Stan

#52 FlyBD5

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Posted 27 June 2013 - 02:44 PM

Shane,

How about metric grade 10.9? That's the metric equivalent to grade 8 std. It's only nomenclature.

Stan


Correct, if it's a metric bolt (I haven't looked at it that closely) then it should be a 10.9 which is equivalent to grade 8 in proof load as well as tensile and yield strength.

#53 FlyBD5

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Posted 27 June 2013 - 02:47 PM

Anything with a handle is not Grade 8, almost by definition.


Well, that's true if the handle is made of the same material and stamped the same way, I suppose, but if you take a strong bolt you can also injection mold the handle or knob over it. Where there's will, I'm sure there's a way. ;)

#54 Cliff Hipsher

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Posted 27 June 2013 - 04:19 PM

You get it very, very close with a Polar scope before you mount the OTA. If the Polar scope is used properly, very little adjustment would be needed. We are talking about fractions of a turn as opposed to cranking on the bolts 8-10 times.


Talk about a "DUH!" moment. This makes perfect sense. Now I'm wondering why this is not covered in the manual?

#55 hottr6

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Posted 27 June 2013 - 04:57 PM

How about metric grade 10.9? That's the metric equivalent to grade 8 std. It's only nomenclature.

Stan,

Yep, 10.9 is sort-of similar to Grade 8, but in metric.

Alas, it is not just nomenclature. There are very different standards applied to Grade 8 and 10.9 fasteners. Metric fastener grading is subject to ISO ruling. Grade 8 does not follow ISO rulings. E.g., there are no standards for surface discontinuities on any inch-standard fastener, but there are for metric. There is more reading at ASTM's (formerly the American Society for Testing and Materials) website than all of us here at CN could consume in a lifetime.

#56 TennDon

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Posted 27 June 2013 - 05:00 PM

What I don't understand is how people manage to break or bend these screws. Don't they notice that the adjustment is getting difficult to move. Do they keep going until something breaks rather than stopping and finding out what is happening?

Chris


I always try to give my CG5 alt/az bolts a helping hand by gently pushing the mount is the direction I want it to go. Haven't had any bolt-bending or breaking off problems. Just my $0.15 worth ( adj. for inflation :foreheadslap:).

#57 SKYGZR

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Posted 27 June 2013 - 05:51 PM

You get it very, very close with a Polar scope before you mount the OTA. If the Polar scope is used properly, very little adjustment would be needed. We are talking about fractions of a turn as opposed to cranking on the bolts 8-10 times.


One can also adjust via the tripod legs (best method if scope is already mounted. It's a bit tricky, yet with practice works well.). When close, then fine tune with the adj bolts while giving it a "helping hand" by reaching around to the CW shaft.

#58 FlyBD5

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Posted 27 June 2013 - 05:52 PM

The mount is fixed. Piece of bolt retrieved from inside the knuckle joint, and it definitely failed as I would have expected a soft bolt to fail under torsion force as I was trying to remove it. Threads are just fine, I replaced the bolts with the knobbed ones from ScopeStuff and they fit fine with a little lubricant.

#59 jrbarnett

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Posted 28 June 2013 - 05:24 PM

Can't help you there. But this post isn't about the LXD75. It's about the CG-5 as the thread title indicates. Does the LXD75 also have spaghetti noodle bolts?

For visual use with a CG5 there's no need to do anything more than align Polaris with the polar scope axial bore hole. You can do that without loading the saddle. Then load the saddle, apply the counterweights and proceed with a 2 star alignment and 3 or 4 calibration stars. You'll be bang on all night and will never bend or break the flimsy little bolts.

With the LXD that requires you to make adjustments loaded, I'd suggest having a buddy help maybe. Someone lifting up lightly on the counteweight shaft while you make the bolts go will really lessen the work being done by the bolts during adjustment.

The Atlas EQ-G is even a bigger joke than the CG5 in this regard. Same flimsy painful bolts but much more head mass to move with them, loaded or not. I replaced those with big all stainless steel bolts with knurled hand knobs from McMaster-Carr, but even with those the buddy system helps during alt-az adjustments, loaded or not.

Regards,

Jim

#60 Cliff Hipsher

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Posted 28 June 2013 - 07:06 PM

Can't help you there. But this post isn't about the LXD75. It's about the CG-5 as the thread title indicates. Does the LXD75 also have spaghetti noodle bolts?


Yep. The Celestron and Meade GEMs are cousins... When I have an OTA aboard it is impossible to move the mount in ALT by just turning a bolt. If I need to raise the mount (RA axis is too low), I make sure the North bolt is loose, and then I "lift" the optics to take weight off of the South bolt, and then I turn the bolt. Needless to say it takes several iterations to get to where you need to be.

With that being said, next time I get to go out (the weather and seeing/transparency have not been very good lately...), I'm going to try doing a polar before I load the mount and see how it goes....

#61 dragonslayer1

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Posted 28 June 2013 - 08:48 PM

there was a thread about this topic somewhat; adjusting the polar alignment with hardware... I seem to remember they were saying they found this like heavy duty waxpaper they put between mount head and base. It holds up forever and makes the head rotate so smooth and easy. It was not too long ago in the mount section, mabey under GEM polar align?? not sure but would be worthwhile finding and checking it out.
Kasey

#62 dragonslayer1

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Posted 28 June 2013 - 09:00 PM

Found it, is about 7 pages back under " improving polar alignment", talks about this UHMW product,
Kasey

#63 FlyBD5

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Posted 14 July 2013 - 11:14 AM

After a couple of weeks I can confirm the ScopeStuff replacement bolts fix this issue. No more problems. I'll probably replace the aluminum plate that screws into the mount and through which one of the bolts threads with a steel replacement. Easy enough to get it cut, drilled, countersunk and threaded...






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