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NexStar Evo 8: tightening the tripod center bolt

Celestron tripod
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#1 tdp

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Posted 17 August 2019 - 04:29 PM

Hi,

 

First posting here after learning a lot from the site, many thanks to all you people for keeping it alive and buzzing.

 

I've just assembled a brand new Evo 8 and tried it under semi-cloudy skies here in downstate NY yesterday - great improvement from a 5" Mak.  

 

Now on to the question: how tight do you guys make the nut on the tripod center bolt (below the tray)?  It seem to me that given the geometry of the tripod legs, it is pretty easy to over-tighten it (by hand) to a point where it puts too much stress on the joints at the top of the legs.  

 

Also: the way the tray rests against the legs, having two very small contact areas on each leg, looks like a possible risk of making dents in the legs. I'm almost tempted to grab a Dremel tool and make cylindrical "notches" in the tray to make the contact areas larger and better fit the legs, but of course I will not do it on a brand new piece of equipment.  Another possibility would be to use little pieces of rubber (inner-tube thickness) between the tray and the legs, or perhaps some thick tape - anybody out there doing any of this?

 

Many thanks for any feedback.

 

 



#2 junomike

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Posted 18 August 2019 - 06:44 AM

I usually go as tight as i can however snug should be sufficient.

Unless the Tripod legs are 3" or larger, most I encounter have dents from tightening.  IMO it's excessive but normal.



#3 NMBob

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Posted 18 August 2019 - 08:43 AM

Cool! Glad we could be of help. :)

 

I don't ever go real tight. As you tighten you can see the legs start to spread apart a little more, or you can feel them spread apart when you tilt the tripod and get the rubber feet off the ground. I stop when those things stop happening. I just keep pushing down on the top of the tripod while tightening and when I can't feel any wiggling I stop. The spreader can only stiffen things up so much given that it is so high on the legs. A stiffener needs to contact the legs further down or even just above the feet to really work well. I think one that pulls the legs in towards the center works better like the old original 'crutch-shaped' tripods Celestron used in the 70's, but the current tripod does OK. After a couple of years I STILL haven't actually done any tests, but I always use the Celestron anti-vibration pads on cement. They don't seem to hurt anything. :)

 

I don't like that V-shaped notch, either. I guess that maybe makes the same part work for the different tripod leg tube diameters they have. It doesn't look like I've tightened things enough to make any dents in a couple years. I don't know if a little rubber would help... If the scope were 50lbs and not well balanced you could envision how that joint might move and the scope tip a little as the rubber on the 'heavy side' compressed a little more, but with the stock setup it might not matter. Split the side of a short piece of thin-ish Tygon tubbing and slip it over the V. Three of them might stay put long enough to get the thing together. I may have to try that. If rubber pad on cement helps a little... It could dampen things a bit.

 

Bob



#4 tdp

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Posted 18 August 2019 - 04:16 PM

Thanks a lot for the quick responses.  My reason for adding a layer of material between the legs and the tray is mostly the (anti-) aesthetics of two non-matching metal surfaces grinding against each other.

 

 Here is the result of my effort so far, the tubing is from a pressurized washer hose:

 

tripod.jpg


Edited by tdp, 18 August 2019 - 04:17 PM.


#5 NMBob

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Posted 18 August 2019 - 06:49 PM

Oh yeah. That'll work!




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