# Walthers 90' turntable kit



## Dennis461 (Jan 5, 2018)

DO NOT BUY THIS TURNTABLE
UNLESS you like scratchbuilding, kitbashing, repairing .

There have been numerous posts over the years regarding the less than adequate performance of this 90’ Walthers turntable kit. (links at end of post). I received this as a gift and feel compelled to assemble it and squeeze it onto my tiny layout.
The major issue is plastic parts which are too ‘sloppy’ for making a precision mechanical mechanism.


1)	Following the assembly instructions, I was left with a turntable that would rotate 180 degrees and then the main ring gear would move away from the motor gear, thus stopping rotation. Assembled, the main ring gear does not rotate in a perfect circle. And the motor/gearbox is mounted on fixed plastic pins; there is no adjustment available in the design. Even an adjustment would not help, as, moving the motor closer to the ring gear would then cause binding on the larger part of the ring gear circumference. I do not think the ring gear is out of round, but it does not center itself on the turntable shaft. Or the turntable shaft is not centered with respect to the bearing surface in the pit bottom. 
Picture #1.










1a)	I modified the motor attachment to include a spring loaded tensioner which allows the gears to stay meshed with an out of round or wobbling ring gear.









1b)	The motor mount has two locating pins which keep the motor (gearbox) in place. By filing down one pin, and leaving the mounting screws slightly loose, the motor can be made to pivot. 

Picture #3










1c) A bronze spring mounted into a new slot provides tension. 

1d)	One mounting hole needs to be elongated on the motor/gearbox to allow pivoting. 









Picture: motor installed









2)	The electrical wipers are made of brass or bronze, while we all have come to expect nickel silver for reliable electrical moving parts, e.g. train wheels. In addition, the large size of the wipers allows the top one to catch on the ring gear and the bottom one to catch on housing bottom. When the wiper catches on the ring gear, it gets pushed away from the slip ring, breaking the electrical connection. The track power stops.

2a)	I’ve ground away some wiper material to minimize this issue.
Picture #4.










3)	An out of round pit is causing the ends of the turntable to drag on the pit walls.










3a)	I’ve sanded down the bridge ends including the wheel carriers and will make further corrections when installing on the layout, forcing the pit to maintain a perfect circle.

4)	As for rotating, I am not sure if the design is meant to have the turntable supported by the center bearing or the outer bridge wheels. With no spring loading, it can’t be both. And as others have reported, the wheels are not round.

5)	I added an LED into the operator’s stall, connected to the bridge track. I run DC, so the LED will light up before the engine moves ‘forward’, I should have installed two with different colors to let me know if track power is making it to the rails, AND which direction the engine will move. The kit is too hard to modify once built. If you want lights installed in a neater arrangement, do it early in the construction.

One last thought, if anyone has built this kit, please post your experience and any lessons learned, thank you.

http://cs.trains.com/mrr/f/88/p/193380/2286126.aspx
https://www.trainboard.com/highball/index.php?threads/walthers-90-turntable.41431/

https://www.bachmanntrains.com/home-usa/board/index.php?topic=6527.0;wap2


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## gregc (Apr 25, 2015)

i found that the large gear would drop. I drilled a very small hole in the shaft directly below it an pushed a stiff wire thru it to hold the gear in place

i also drilled a hole thru the center of the box where the shaft sits, drilled/threaded a hole in the center of the bottom of the shaft and used a screw/washer to hold the shaft down in place.

i sanded the ends of the turntable it prevent them from rubbing against the side of the pit

i added an quadrature encoder to the motor and was working on indexing SW. I haven't been able to repeatedly reposition the turntable. i'm not sure if it is skipping (jumping teeth) in one or both directions possibly because the large gear tilts and isn't firmly aligned with the worm gear.

the photo shows an inspection hole i cut in the box.


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## flyerrich (Feb 17, 2014)

*not worth it to me*

Surprised that Walthers continues to sell this item. After all the problems encountered by anyone trying to make it work satisfactorily. I don't feel it would be worth my effort to add all the changes/additions to get something that bears the initial cost and still not very dependable.
Are their any others out there that are more reliable?


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## MichaelE (Mar 7, 2018)

Märklin, but it's probably AC unless you are able to use your own trackage. They aren't cheap, but you can bet it will work with German made precision.


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## gregc (Apr 25, 2015)

flyerrich said:


> Surprised that Walthers continues to sell this item.


the current 90' model, 933-2860 is very different. I think it's full assembled, the motor with encoder are located in the bridge, the pit has a toothed ring the bridge rides on, there is an electronic indexing control and it works very well.


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## mesenteria (Oct 29, 2015)

I did all sorts of fixes for this wretched kit and finally abandoned it altogether. I had to add a large spacer washer, about 2" in diameter, under the large gear in order to stabilize the entire shaft. I had to shim the motor, and had to add plastic washer spacers under each brass ring to keep the wipers up against each ring. Even then, the pit wasn't sufficiently true to allow the bridge to pivot properly.

In the end, I paid the bucks for the then new 90' 'built-up' and indexed version which worked very well for me. My only complaint about it, and Walthers' instructions did caution the user about it, was that the mechanism at the end of the bridge and the pit would indeed need cleaning regularly in order to get long and reliable use from the product. Even though I vacuumed it before each use, after 18 months I found performance beginning to suffer, so I opened up the drive at the end of the bridge and found all sorts of bits of ground foam, pet hair, and other stuff. But, it worked sooooooooo much better than the kit.

Don't buy the kit. Save for another two months and buy the indexed version.


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## D&J Railroad (Oct 4, 2013)

Another product that looked good on paper and the engineer model, but the production version, a whole different version. To much invested in the development so just push it out the door anyway.


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## gregc (Apr 25, 2015)

there are a few versions of walther's turntables. Looks like they've continued to refine them. As others have said, the current one works well

933-2616 N assembled DC/DCC 130'
933-2618 N assembled motorized 130'

933-2829 HO assembled motorized 130'
933-2849 HO assembled DC/DCC 90'
933-2851 HO assembled motorized 110'
933-2859 HO assembled DC/DCC 130'
933-2860 HO assembled motorized 90'

933-3171 HO kit w/o motor kit 90'


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## Cab1 (Jul 26, 2009)

I'm interested in the Walther's 933-2829 HO assembled motorized 130' turntable. Are they any good? I have some big honking steamers to turn in a small space.


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## Jima (Oct 28, 2018)

I have one and I run mine with a 5 fingered motor. It is not the smoothest but it works for me.

Jim


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## LateStarter (Mar 12, 2016)

Years ago (mid 80's) my brother scratch built a turntable, with under-table reduction-gear linkage connected to a hand crank. It still works smooth and flawlessly.
Indexing is done with a roller/ball/detent system, which is now hooked to a panel of LED's -- but only because he's a gadget guy... (you can feel the detents in the crank).
It serves an 8-stall roundhouse converted for diesel use, plus a fuel & water facility (old CB&Q prototype).
It's still the best working turntable I've ever seen.


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## gregc (Apr 25, 2015)

a reliable turntable design uses a plate under the layout driven with a motor having a rubber end (eraser) pressing on the plate and using optical detection. 

metal or cardboard flags can be attached to the rim of the plate so that the pass thru a slot detector. One edge of the flag determines position. An Arduino can be used. Friction drive allow slip if something blocks the turntable.

http://www.pacificsouthern.org/Images/IMG_0565a.jpg (yet another img that won't display on this forum)


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## Dennis461 (Jan 5, 2018)

*still struggling*

I made a mock up of my planned layout to test some track plans and see how the turntable is going to work out.

Turns out the thing is not symmetrical.
I lay track for a straight through run into the roundhouse.
Put a few spikes in and run five engines through with no problems.

Reverse the turntable 180 degrees and the tracks do not line up.
Now since the kit has pins to align the deck, and no wiggle room for the rails, I am currently at a loss as to correcting the issue.

I may have to remove the CA glued rails, install a new flat deck on top, and find the true center line.


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## Atlanta (Apr 29, 2019)

The Walthers Cornerstone Turntables are coming from Heljan in Denmark.
The kits are cheaper than ready to run turntables. But product lines maybe manufactured in china and than distributed by Heljan to Walthers Cornerstone productline.
The most expensive turntables coming from Märklin in AC version or Trix in DC version.

Roco or Fleischmann have each one big and small diameter motorized turntable in their product lines. 

More cheaper is the turntable from the british peco but the peco turntable needs a motordrive by your own choice, it are unpowered only.


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