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From the Only Dumb Question is the One Not Asked Department

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  • Member since
    December 2004
  • From: Bedford, MA, USA
  • 21,483 posts
Posted by MisterBeasley on Saturday, April 14, 2018 1:28 PM

rrinker

 I guess we ought to know just what turntable is involved here. If it's an Atlas, with its geneva mechanism, no need for a momentary switch, the indexing is fixed and mechanical. If it's a free-spinning turntable like one of the Walthers kit ones with the motor added, then a momentary switch is kind of needed to jog the table into final alignment if there's no indexing. 

                              --Randy

That's a good point about controllability.  I have an Atlas, but I "pit-bashed" it so the alignment is not as perfect as it would have been if I'd just left it as a deck turntable.  (But what fun would that have been?)

I do have to jog the turntable to get proper alignment for some of the stall tracks.  My control toggle is a simple DPDT center-off, and I'm able to align it without any trouble.  The Atlas drive is slow enough and I run it at reduced voltage.

It takes an iron man to play with a toy iron horse. 

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Saturday, April 14, 2018 9:58 AM

 I guess we ought to know just what turntable is involved here. If it's an Atlas, with its geneva mechanism, no need for a momentary switch, the indexing is fixed and mechanical. If it's a free-spinning turntable like one of the Walthers kit ones with the motor added, then a momentary switch is kind of needed to jog the table into final alignment if there's no indexing. 

                              --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    January 2009
  • From: Bakersfield, CA 93308
  • 6,526 posts
Posted by RR_Mel on Saturday, April 14, 2018 9:14 AM

I built up my own indexer to auto select the tracks but I also have manual control using two switches as shown in the drawing below.
 
 
If the motor in your turntable coasts after removing power I have a fix for that too.
 
 
 
Mel
 
Modeling the early to mid 1950s SP in HO scale since 1951
  
 
My Model Railroad   
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.
 
  • Member since
    December 2004
  • From: Rimrock, Arizona
  • 11,251 posts
Posted by SpaceMouse on Saturday, April 14, 2018 8:49 AM

PC101
Spacemouse, you will want to use a momuntary switch (as mentioned above by RR_Mel) to run the turntable CW and CCW (returns to center off by it's self) Sorta like a deadmans pedel, so if you fall off your seat, the turntable will stop moving. You just release the pressure on the lever and it returns to center off.  Eliminate the two switch (one for direction DPDT and one for movement, momuntary) setup and just use one switch, DPDT center off ,momuntary.

Yeah, I know you're right. I worked this out before I read the forum this morning. And now, when I think about it, the turntable on club layout I belonged to in PA had a MOM.  

Done. On it's way from East eBay. Only a week's delay. Sigh. I need to get the rough wiring done so I can button down the plywood and lay some track. I wanna hear some chugga-chugga choo-choo. 

Chip

Building the Rock Ridge Railroad with the slowest construction crew west of the Pecos.

  • Member since
    March 2012
  • 1,162 posts
Posted by PC101 on Saturday, April 14, 2018 7:00 AM

Spacemouse, you will want to use a momuntary switch (as mentioned above by RR_Mel) to run the turntable CW and CCW (returns to center off by it's self) Sorta like a deadmans pedel, so if you fall off your seat, the turntable will stop moving. You just release the pressure on the lever and it returns to center off. 

Eliminate the two switch (one for direction DPDT and one for movement, momuntary) setup and just use one switch, DPDT center off ,momuntary.

  • Member since
    July 2009
  • From: lavale, md
  • 4,678 posts
Posted by gregc on Saturday, April 14, 2018 5:15 AM

greg - Philadelphia & Reading / Reading

  • Member since
    December 2004
  • From: Rimrock, Arizona
  • 11,251 posts
Posted by SpaceMouse on Friday, April 13, 2018 11:59 PM

This is easier than the way I was going to do it. 

RR_Mel
Use a momentary-center off-momentery if your not using a seperate run switch.

I doubt the switch I have is momentary. So you are saying I use this to control direction, but I need another switch to run the motor.

Chip

Building the Rock Ridge Railroad with the slowest construction crew west of the Pecos.

  • Member since
    January 2009
  • From: Bakersfield, CA 93308
  • 6,526 posts
Posted by RR_Mel on Friday, April 13, 2018 10:39 PM

You got it!
 
 
 
Use a momentary-center off-momentery if your not using a seperate run switch.
 
 
 
Mel
 
Modeling the early to mid 1950s SP in HO scale since 1951
  
 
My Model Railroad   
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.
  • Member since
    December 2004
  • From: Rimrock, Arizona
  • 11,251 posts
From the Only Dumb Question is the One Not Asked Department
Posted by SpaceMouse on Friday, April 13, 2018 9:38 PM

I want to use DPDT switch to be able to spin my turntable in both clockwise and counter-clockwise directions. Assuming I'm using Red and Green wires, is this the way it should be wired on the six poles?

R-R-G

G-G-R

Chip

Building the Rock Ridge Railroad with the slowest construction crew west of the Pecos.

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