TAL of Two Cities-2M Mount

[Starman18]

I have a 2M Mount & 100R Refractor. The RA Drive motor has (at least) worn bearings! The Prior owner mounted a HEAVY 6" Refractor on it.  I think the Synchronous Motor is 12 volt AC, 60 Cycle, 0.2 ROM Clockwise Rotation.   While the original Finder was replaced with a cheap Chinese model, I really am more concerned with getting a new motor. I am in the U.S. and thought I'd have no problem getting another similar motor or ordering a new usable motor from some Manufacturer.  I understand TAL is out of Business.  Well, like trying to view today's Conjunction (Clouds), not much luck !

 

Any suggestions Please? Thanks

[John]

This is a USA based TAL vendor. They might be able to help:

http://talteleoptics.com/

 

 

[DaveL59]

welcome aboard.

Is it the RA motor or the gearbox internals that are worn?

UK based but they may be able to rebuild if they are still in business, or there may be someone in the US that can service the gearbox
AWR Technology (Astronomy - Electronics) Telescope Maintenance

 

[Starman18]

Many Thanks John and DaveL59, will follow  up. Plan on removing this motor soon, time will tell.

Thanks Nick

[DaveL59]

good luck with the investigations. Depending on how mechanically minded you are it may be possible to replace with alternatives. @markse68 on here rebuilt his with a different motor and gearing so may be able to offer some advice on that front. I think he detailed it on a thread on here too.

[R26 oldtimer]

A 6" frac isn't an excessive load for this mount and in any case it would not cause any damage to the motor itself.

There are two different friction clutches in the RA gear train that prevent damage to the motor and allow manual movement, my guess would be that they need some adjustment.

There are two pdfs on the mount's strip down in this thread.

 

Edited December 27, 2020 by R26 oldtimer
Added link

[markse68]

33 minutes ago, R26 oldtimer said:

A 6" frac isn't an excessive load for this mount and in any case it would not cause any damage to the motor itself.

There are two different friction clutches in the RA gear train that prevent damage to the motor and allow manual movement, my guess would be that they need some adjustment.

There are two pdfs on the mount's strip down in this thread.

 

Wish I’d seen these before I took mine apart- would have saved a lot of hassle!

I did replace the motor in my Tal-1m which was worn out with a stepper as Dave said but it involved building a whole new gearbox for it

If I were to do it again (I might as i also have a 2m...) I’d probably look to see if one of these little geared steppers could fit in place of the original motor unit- I don’t think i considered these first time round. An Arduino and a smooth stepper driver with one of these might work but I haven’t looked at torque requirements yet

https://www.ebay.co.uk/itm/201999043536

Mark

[Starman18]

1. An Edit-rotation is .2RPM,Not Rom. Getting OLD

2. Emailed talteleoptics/AWR-thanks John/daveL59. Hope get some replies.

3.Removed motor & gear/clutch combo. Lots of shaft wiggle against nylon gear.  Also takes 4-5 seconds for motor to actually rotate!

4. Seems like gear issue. OTA weighs a good 25 pounds (not currency). Ideas R26oldtimer?

5. If no replacement motors thinking a #17 Stepper/Driver solution. Looking for "KISS" first !

[DaveL59]

does this help at all?
THE FIRMAMENT - Solar System and Deep Sky webcam images

There's a number of posts on here on the motorised mounts tho how much they'd help I can't say, likewise on cloudynights forum. 

 

[Starman18]

An update to all (again Thanks):  I learned AWR no longer "fixes" these motors/Talteleoptics provided no response! TAL Yahoo Group(s) are Gone!  Didn't locate TAL motor info yet on CN. Thanks markse68-info is good. will see once motor issue fixed. Hoped to not do a stepper system(have too many projects already).

Have yet to open up the motor to look at bearing change. Have a small Lathe.  Battle continues...

[Starman18]

Ok, final part of the "story" all, USA Vendor for TAL states NO parts!  NO exact match with US Motor makers. So decided, what the heck ! I took the gearbox off the motor and measured everything, including that darn nylon bearing for the output shaft (only). I found a bronze part somewhat similar in size and fired up my MiniLathe (still learning about it's features).  I actually made this part into a bearing a little bit wider on the "outside" face and using screws in the 3 metal posts and epoxy glue, put it together. Just tried it, works great! What a relief ! I would not want to repeat that again, but does seem fine. It IS possible to do it yourself IF you have a lathe. Many thanks to all member support. Nice to have your help! Stay Safe.

[markse68]

That’s excellent Nick! Nice to know it’s possible and another Tal mount is going back into action  How are your axis bearings? I’m in the process of replacing all of mine as they were all notchy.

Mark

Edited January 14, 2021 by markse68

[sloz1664]

Excellent result Nick. 10 years ago I did source a couple of motors from Yuri, the Tal spares specialist based in Novosibirsk, Russia. I used one myself and the spare went to a guy in the States about 6 years ago. Tal products and spares are getting rare these days.

Steve

[Starman18]

Thanks Steve! It is more work than I wanted !

Thanks Mark, I had hoped my "work' was over (more projects to do), but I have now run into that "notch" problem too ! Give me a break !  While the drive wheel/worm combo feel just fine, I need to also fix these issues before selling it off. I originally bought the OTA & Mount for a scope for one of my two grandchildren (one has a Russian Father), I had a change in philosophy (?) as my other Grandchild (1/2 sister) I thought should also share in Astronomy, so I already have two Edmund Refractors I will provide upon my death (some years hence).

Looks like I am rebuilding the TAL, but she deserves it.