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CGE mount- movement between pier/head/tripod

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#1 scout72

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Posted 24 June 2009 - 10:53 AM

Thsi is a new to me CGE and the first one I have used, and I am concerned about the play in the mount head between the electronics pier and the head and the pier and the tripod- all of the play (about 1/16" or so)appears to be related to the six connecting bolts (three at the head and three at the tripod). I have the ADM knobs as well as the original hex head bolts with washers and the problem is there with all of them, unless I REALLY clamp down the hex heads.

It looks like the diameter of the bolt threads is slightly (that 1/16") smaller than the hole in the electronics pier and this is allowing the play.

it seems liek some kind of thin sleeve would fix the problem, but I don't see this discussed anywhere...is this a known issue? The holes in my setup appear stock and not modified in any way, and under normal balanced load (25lbs) I have not noticed any problems, but when I push on the counterweight shaft on the unloaded mount I can see it moving which bothers me.

Anyone else notice this / have suggestions?

#2 freestar8n

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Posted 24 June 2009 - 11:40 AM

Hi-

One thing I would check, that is somewhat surprising, is that the top two screws of each tripod leg should be tight. The two screws at the pivot/hinge near the top. If these get a bit loose, the electronics pier will flex a bit if you apply pressure to the dec. axis. It surprised me that this was linked to the tripod legs, but it was for me. So - make sure they are tight. They loosen with each open/close of the tripod and need periodic tightening.

Frank

#3 DaveJ

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Posted 24 June 2009 - 01:03 PM

Hi Scout72,

Here's my solution to your difficulties:

The yellow handle is a 3/16" T-handle hex wrench
The red handle is a 7/32" T-handle hex wrench

Both are readily available at any good hardware store. You can place LOADS of torque on the screws holding the mount to the pier and the pier to the tripod. I use the yellow handle wrench to tighten the tripod screws (after the tripod is set up to use) and to loosen them prior to collapsing the tripod for transport. As a plus, the yellow handle tool is also used to adjust the altitude of the mount!

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#4 scout72

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Posted 24 June 2009 - 01:46 PM


Thanks for the suggestions...I have made sure the tripod leg bolts are tight, and that did help overall, but this is specific to the 6 other bolts.

I guess I will only use the stock bolts and apply LOADs of torque- kind of a bummer since the ADM knobs are so easy to use, and came with the used mount I bought!

#5 mclewis1

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Posted 24 June 2009 - 06:21 PM

I found I had movement at the top of the electronics "pier" when I used the ADM knobs ... I simply couldn't tighten them down enough. So I started re using the stock bolts torqued down nice and tight. The ADM knobs seem to work well at the base of the pier so I can still easily move the eq head to and from the tripod if necessary.

It would be nice if there was a more positive connection that could still be held by the ADM knobs without having to be superman to tighten them down.

#6 scout72

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Posted 24 June 2009 - 09:53 PM

I agree- and I am thinking some kind of sleeves would do the trick- I am going to see if i can find some that will work and will post results either way.

#7 Arbacia

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Posted 25 June 2009 - 05:26 AM

I am using the original bolts but using a Bosh axio electrical screwdriver (samll size, not very powerful). It is faster than ADM bolts and not tighting very hard. If needed I use Allen tools

#8 Americal

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Posted 25 June 2009 - 02:28 PM

Similar problem on my CG5 but on the leg mounting bolts, they're smaller diameter than the bosses on the tripod head. I figured I'd machine down new bolts of shim the existing. I like cheap and easy. Most good hardware stores and hobby shops have a selection of thin wall brass tubing, it wasn't an exact fit to the bolt but I split the tube on one side and it was real close and all play is gone. My vote, try shimming the bolts.

#9 Arbacia

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Posted 25 June 2009 - 04:30 PM

Similar problem on my CG5 but on the leg mounting bolts, they're smaller diameter than the bosses on the tripod head.


I realized that some days ago on the CGE5 GT belonging to a friend. I was thinking to use a small section of a thin-walled tube to fix it.

#10 Eddgie

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Posted 26 June 2009 - 11:26 AM

Just my own experience.

First, I do not seperate the half-pier from the mount head. I use the original screws and tighten them pretty tight.

Next, I use 3 large knurled knobs that I bought from McMaster Carr. These are quite large and have a nice knurling for gripping.

I DO use the washers that came off of the factory original hex nuts between these knobs and the pier.

Next, when I put the peir in place, I TIGHTEN THE REAR KNOB FIRST. I tighten it as snugly as I can get it by hand. My experience is that the Counterweights will pull against this screw point trying to tilt the mount forward. The north side of the mount is under compression, so this does not matter as much.. But the back screw is the one that has to be tight.

THEN, I thighten the NE and NW knobs. These don't have to be nearly as tight. And you can get the rear one pretty tight if you put it in and tighten before you put in the other screws.

I don't have any problems with play when using this method. And because all of the play is out from between the rear of the Semi-pier and the hub, even if you tighten it pretty tight, it still comes out with hand pressure.

I also like the fact that I can stand the head on the semi-pier on table and let the CW shaft stick out over the edge. In two years, I have never needed to remove the semi-pier from the head. So unless you have some compelling reason for doing so, my advice would be just to put in the factory screws and washers, tighten, and call it good.

Regards.

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#11 Eddgie

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Posted 26 June 2009 - 11:31 AM

By the way, these knobs sell for only about $3.00 each.

#12 scout72

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Posted 26 June 2009 - 11:31 AM

That is great information- and makes a lot of sense. Thanks for the reply.

#13 scout72

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Posted 27 June 2009 - 12:36 AM

Well, here is my quick fix, since I already have the ADM knobs, I wanted to see if some kind fo sleeves would help first, and they do!

I used brass grommets with 3/8" ID- like this:

grommets $3.89 10pk

I used a large washer to push down on them to fit over the threads on the ADM knobs.

I snugged them all up after putting grommets on all six knobs and it is completely movement free now.

Will have to see if they hold up afte a couple of break downs/set ups but pretty happy for now.

Thanks again for all of the suggestions.

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