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Stress cracks in tripod clamp housing

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#1 chemist

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Posted 14 January 2013 - 12:51 PM

While doing some maintenance on my scopes I noticed stress cracks that have formed in the plastic that houses the clamping screws that secure the tripod leg extensions. The cracks are around the threaded brass inserts. I guess I always thought that these parts were metal, but they are not.

I have attempted a repair by filling the cracks with two-part epoxy. If this doesn't work I'll be looking for a better fix or better tripod. Has anyone experienced the same problem? If so, what was your fix?

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#2 Bob Griffiths

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Posted 14 January 2013 - 01:37 PM

LOL>...I pulled one of the inserts completely out of one of my tripod legs.. Simply over tightening it ..but I guess it must have had some "stress cracks" present that I never noticed...

Since it was only one leg and I normally set up the tripod at the same height I just drilled a hole thru the two legs and bolted them together..Been fine for a number of years BUT I now only have 2 adjustable legs..

Bob G.

#3 herrointment

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Posted 14 January 2013 - 03:45 PM

After overtightening and cracking all three of those plastic wonders I ditched the legs and built set out of wood.

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#4 Peter9

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Posted 14 January 2013 - 04:02 PM

Same as Bob here. I too pulled the brass insert out of one of the plastic mouldings.
Because my tripod is housed in my observatory, and as such, I have no need to adjust the height, I have made a splint for the damaged leg.
Should I need it to be adjustable again, I would drill through the moulding and through the inner leg at three or four different heights, say two inch apart, and pass a metal or wooden pin through.

Regards. Peter.

#5 Midnight Dan

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Posted 14 January 2013 - 10:52 PM

I've been very careful in tightening the clamps. It really requires surprisingly little tightness to get a good clamp on the leg.

But, if you already have cracks, I'm not sure epoxy alone will work. I've had a similar problem with a music stand and was able to repair it very solidly using kevlar and epoxy. Kevlar fabric can be purchased in small quantities on ebay. Use an epoxy that takes a good 30 minutes of working time so you have time to work with it.

Cut strips of the Kevlar fabric to lay over and around the cracked spot. Mix up some epoxy and spread a thin layer onto the leg clamp housing. Lay the Kevlar strips over it and, using a disposable tool like a popsicle stick, press the kevlar into the wet epoxy. Spread another thin layer of epoxy over the Kevlar.

When you're done and it's dry, it won't look pretty, but it will be solid! You can sand it a bit and paint it black so it doesn't look so bad.

-Dan

#6 sonny.barile

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Posted 15 January 2013 - 12:00 AM

Well they had to achieve the "price point" somehow!

#7 StarStuff1

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Posted 15 January 2013 - 08:23 AM

In late 2009 I purchases a new Celestron 130 SLT. After the initial set up it was obvious that the legs of the tripod were a weak spot. I modified some oak legs for a tripod I made years earlier for a different mount. The wood legs made a world of difference!

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#8 sonny.barile

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Posted 15 January 2013 - 06:39 PM

Great! Something else for me to obsess over. Now I will examine my tripod 20 times a day waiting for it to crack.

#9 CelestronDaddy

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Posted 15 January 2013 - 07:51 PM

Great! Something else for me to obsess over. Now I will examine my tripod 20 times a day waiting for it to crack.

:lol:

#10 Midnight Dan

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Posted 15 January 2013 - 08:55 PM

Always good to have something to obsess over! ;)

All seriousness aside though :smirk:, it's a good idea to very lightly tighten the clamps, and then make an effort to change the leg length with your hands. Keep tightening a very little at a time and try again. When you've got it to where it's pretty difficult to move, you know it's tight enough. You'd be surprised how little it takes. That will give you an idea of how much force you should use when tightening.

-Dan

#11 Brent Campbell

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Posted 15 January 2013 - 10:35 PM

Look on Ebay for a tripod from another nexstar that went south. I did this on mine and even though the tripod head wasn't the same the leg swap- out was easy.

PM me if you want to purchase the legs. My mount went nonworking after I fixed my tripod.

#12 barbarosa

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Posted 15 January 2013 - 11:10 PM

The last time this happened, I tried roughing up the area then using epoxy and brass strips to bridge the cracks. It seemed to work well. Then a few days ago (temperature ~35F), I forgot to be gentle and heard a snap. The repair did not entirely fail, so I second the idea of using something to add mechanical strength.

#13 Greyhaven

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Posted 16 January 2013 - 11:51 AM

Chemist
I feel your pain I've also lost a tripod leg on my Nexstar 5i. I kept the other two. PM me Maybe I can send you a replacement.
Be Well
Grey

#14 bcuddihee

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Posted 16 January 2013 - 04:23 PM

These are very lightweight tripods for the load they are carrying. I would suggest for durability as well as stability, that you move up to a Celestron HD tripod, as found on the c11.

#15 Geo.

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Posted 18 January 2013 - 07:21 PM

These bicycle seat post cam over clamps available in 1-3/16, 1.25 and 1-3/8" and make good replacement tripod leg clamps.






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