Tube rings greatly reduces vibration and shaking in the Nextstar 130SLT tube.

[Nordmann61]

On the Nexstar 130SLT the dovetail plate is attached directly to the sheetmetal wall on the tube with four screws.

On the inside of the tube there is a metalplate to distribute the load on the four screws with nuts.

That the dovetail plate is directly attached to the sheetmetal wall of the tube, and give in the sheetmetal, is the main reason for the 130SLT being so prone to shaking. It is not so much the mount and the light tripod as it is easy to think. The weight of the 2 inch focuser, with 2 inch to 1,25 inch adapter and eyepiece on the opposite side of the dovetailbar also contributes to swinging mass.

I suspected this because the 102SLT, has almost no complaints about shaking compared to the 130SLT.

The 102SLT also has its dovetailplate attached directly to its tube wall, but the 102 tube is of smaller diameter, and has a seamless aluminium tube with thicker walls.

This makes the 102SLTs tube more rigid, and almost no shaking as a result.

I also have a Skyscout 90mm refractor on a NEQ3-2 mount, and I swapped the telescopes between the mounts. On the SLT mount, the 90mm with tube rings has almost no shaking, and the 130SLT on the NEQ3-2, shook almost as much as on its SLT mount.

Give in the sheetmetal wall on the 130SLT tube is clearly the main reason for the shaking.

I tried cardboard shims between the tube and the plastic collar on the SLT mounts dovetailreceiver, it helped, but not so much as I wanted. I then thought that traditional tube rings would be a good idea.

The 130SLTs tube outside diameter is 160mm, or 6,3 inches. I ordered SkyTech 160mm rings together with a SkyTech 21cm or about 8inch dovetailplate. Other brands will do equally well I am sure. Make sure that the dovetailplate ordered is of the Vixen/Celestron standard.

The rings came with M6 bolts with washers and springwashers. In order to slide the dovetailbar into the SLTs dovetailreceiver, I had to remove the washers on one of the M6 bolts, because the bolt head could not clear an edge in the dovetailreceiver, then it is no problem sliding the dovetailbar in place.

The SkyTech dovetailbar comes with two M4 Allen setscrews on both side of the M6 holes for the rings, so tightening them secures the rings nicely.

I kept the washer and springwasher on the bolt for one of the rings, the upper ring so to speak, so the telescopetube is secured agaist falling into the ground. The height of the M6 bolt together with the washers catch against an metal edge in the dovetail receiver, preventing the tube from sliding out of the dovetailreceiver if the knob is not tightened securely.

The original dovetailplate is still on the tube, it is enough clearance between the tube and the dovetailplate on the rings for it. Nice to have it there, so I can center the tube on the mount as before.

The tube rings reduced the shaking astonishingly well I am happy to report:)!

The tube rings do not eliminate shaking, but close to. When I poke a finger to the focuser on the 130SLT without the rings, it shakes happily and merrily for 6-7 seconds before the tube calms down. With the rings, just 1 to 1,5 seconds!

The base of the tuberings is 12,5mm or half an inch, bringing the tube the same distance out from the dovetailreceiver. This should not make the telescope point differently I think.

Tube rings on the 130SLT to reduce its shaking, is a simple, inexpensive bolt-on fix. Very much recommended, and in combination with vibration supression pads if it is on a hard surface, greatly improves the quality of your observation sessions. With scope rings, the 130SLT is one of the very best, if not the best grab and go telescope up to 130mm aperture in my book.

Kind regards,

Nordmann61:).

[Nordmann61]

I just want to make this correction in case someone wants to try tuberings on their 130SLT based on the results for my 130SLT.

In my post I wrote:

"When I poke a finger to the focuser on the 130SLT without the rings, it shakes happily and merrily for 6-7 seconds before the tube calms down. With the rings, just 1 to 1,5 seconds!"

I have now carefully measured the time again with tuberings and without tuberings on my 130SLT, and this time I measured about 5-5,5 seconds, not 6-7 seconds as in the first test.

Maybe the dovetailreceiver knob was tightened differently in the first test, I am not sure.

Note, when I poked my finger to the focuser, I poked upwards, when I poke on the side of the focuser the difference is not so great, but it is some improvement with the tuberings here too to reduce horisontal shaking and vibrations, so overall I am still very satisfied with the result with scope rings on my 130SLT, and will still stand by my claim that tuberings on the 130SLT reduces shaking and vibrations, especially vertically for my 130SLT tube.

Kind regards,

Nordmann61.

[Nordmann61]

Hi all,

As an option to traditional tube rings of metal, there is a plastic clamp or ring 4" or 5" wide on a new clone of the SLT made by Orion.

Orion make a new version of the Celestron Nexstar 130SLT, and one thing that is different on this new clone, is the way the tube is attached to the mount.

Orion use a 4" or 5" wide plastic hinged clamp or ring, this will function the same way as traditional tube rings spaced the same distance apart.

Maybe it will be available as an aftermarket accessory or a part SLT owners can order.

The signature Bigbeck on cloudynight.com, Celestron Nexstar forum, informed me about this new clone telescope of the SLT .

Kind regards,

Nordmann61.

Link to the Orion telescope on telescope.com:

http://www.telescope.com/control/pro...oduct_id=09536

[Nordmann61]

The new version from Orion is not really new, it is a clone of the Nexstar GT series, the predecessor to the SLT. I would recommend traditional tube rings of metal istead of trying to fit the plastic clamp or ring to the SLT mount, because:

This plastic clamp on the Orion version looks suspiciously like the one used by Celestron on the predecessor to the SLT series, the GT series.

On the GT it is no dovetailreceiver on the mounts arm that holds the tube, the plastic ring is attached by a center screw. To attach this plastic clamp or ring to the SLT would mean to remove or modify the dovetailreceiver.

In case, I would much more recommend traditional tube rings mounted on a dovetailplate, much better having the convenience of removing and attach the 130SLT tube or another tube by tightening or loosening a knob on the dovetailreceiver.

The signature Bigbeck on cloudynight.com, Celestron Nexstar forum, kindly informed me about Orions new clone telescope of the SLT.

Kind regards,

Nordmann61.

[mtnmx]

Does anyone know the part #'s of the required tube rings and plate to help the shaking issue?   Thanks  T

[iapa]

I use

140mm Skywatcher Telescope Tube Rings

80mm Skywatcher Dovetail Mounting Plates

from FLO