Author Topic: (Actual) Weight Limit for Nexstar SLT Mount  (Read 65 times)

Danny Cruz

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Re: (Actual) Weight Limit for Nexstar SLT Mount
« Reply #15 on: January 18, 2018, 01:49:51 AM »
Aftet owning the nexstar mount, I realized they made their money on the tripod. It worked great for smaller refractors but the shakes were terrible at the 10 lb limit.
Quote

The biggest issue with the SLT mount comes from the tripod and not the ability of the Mount itself.
I put a set of vintage wooden legs on my SLT and it carried a Celestron C6 SCT easily.
You are going to have trouble getting any decent photos, with the way it was mine shook for 6 or 7 seconds. The wood cut that down to about 2 seconds.
I don't know why the Chinese put such obviously undersized legs on their mounts. The Celestron 6 and 8 SE Nexstars are about as bad. While the 6" is OK, the same mount was used for the 8" the result is very bouncy.


soamezquipack

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Re: (Actual) Weight Limit for Nexstar SLT Mount
« Reply #16 on: January 18, 2018, 02:20:49 AM »
Fellow 127SLT owner here. Yes, this mount has a bad rep, and most of it is deserved. But not all of it.

You can read all about this scope at length in my blog in my signature, but I'll try to give you the short, um, well, shorter version.

The SLT mount isn't the sturdiest, but it definitely can be made to be just fine. A few simple things - put a weight on the accessory tray. About 5 pounds or so. Second, go around the entire mount/tripod, and tighten up every screw one quarter of a turn to make the mount even tighter. Don’t tighten more than that, because you don’t want to crack the plastic. Third, don't extend the legs all the way out. The weight and keeping it low help keep the center of gravity low so that the mount vibrates less.

And also, if you keep the scope low by not extending the legs very much, you can observe while sitting down. Observing while sitting isn't for your legs. It's for your eyes. It's so that you can observe instead of just looking. This is because the atmosphere is unstable, and the telescope magnifies that. This is a concept known as seeing. And for a few seconds out of every few minutes, the seeing steadies down, and you have great clarity - details snap into focus. You've gotta observe the moon or planets for at least 5 minutes, not just 30 or 60 seconds, for the seeing to get steady like this.

A fourth thing to do is to make yourself some anti-vibration pads. Don't spend 40 bucks on the ones Celestron sells you. Instead make your own for $1.48:

http://www.homedepot...89077/100172405

Take these and tape some dense foam, like packing foam, into the round cups. These four things will really make the mount much more stable and reduce the vibration time markedly.

Having covered the redeemable, let's get to the bad. I'm on my second SLT mount. I bought this scope from Amazon 14 months ago, last November. After three weeks, a problem just happened for no apparent reason - the handset and the altitude would not coordinate. It took 11 seconds from pressing the up/down button on the handset for the scope to start moving in response. This was infuriating, as you couldn't make fine movements with the handset to center objects. Because I was still within the Amazon return period, I was able to return the scope. In fact, Amazon sent me out a new scope before I had even packed up the old one. That's customer service!

Everything was fine with the second scope, second mount, until this past May. The exact same problem developed with the handset. Worse, the scope was slipping in altitude for no apparent reason - you put it on an object, and it would just start slowly drooping. You had to press the up button to keep the object in the field of view. Again, this was unacceptable.

Since I was still under warranty with Celestron, I contacted them to send the mount - just the black plastic arm and base, not the tripod - and the handset back to them. That was an ordeal in customer service. Took them over two months to get it back to me, not the 30 days as "promised" in their warranty. Much lying on their end, too.

Celestron said that I had a slipping altitude clutch. They tightened it, and all has been well in the five months since getting the scope back. I haven't used it much these past two months because the weather has been positively awful, but it is working as it should.

Now, more to your central concern - the weight limit. For about 6 months there between getting the second scope and the warranty problem, I had an ST-80 bungee-corded to the top of the 127. With the mount, the diagonal, the EP, this added an extra 3 pounds onto the 8 of the 127. I had no problems. For those that say, "Ah, that extra weight caused your altitude problems," I respond that I didn't even own the ST-80 when the same altitude and handset problems developed in the first scope. But I too believe that the extra weight might have contributed to the failure. No way to be really sure.

I think that if you balance out the 127 by moving it forward in the dovetail plate when you attach the camera and camera mount, you should be just fine. I do this when I use my binoviewers, which is a lot these days. Like others have said, that may cause some shortening of the lifespan of the mount, but I would go for it. The mount ain't so great to begin with, so an early demise is not the worst of things.