# My scratch-built turntable



## rva1945 (Feb 11, 2016)

Hi:

I decided to build my own turntable to be installed in a new section that I will add to my existing layout.

I use a stepper motor, an Arduino Nano and a IR remote control.

A couple of videos and the step-by-step album. I hope you like it, regards, Robert.











https://photos.app.goo.gl/F1mvqNDgwY8cKaPg8


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## wvgca (Jan 21, 2013)

looks pretty good, nice result


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## Magic (Jan 28, 2014)

Nice smooth movement on the TT. Good speed as well.

Magic


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## Deane Johnson (Sep 19, 2016)

Very creative work. Congratulations on an excellent result.


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## Stumpy (Mar 19, 2013)

Nicely done!


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## wvgca (Jan 21, 2013)

forgot to ask before, but is it indexed where it stops on the track automatically ?? or just rotation as long as you hold the button down ?


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## MichaelE (Mar 7, 2018)

Nicely done. Is it fabricated from metal or plastic? Looks like metal to me.


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## DonR (Oct 18, 2012)

A very interesting project very well done.

Really like that fantastic F (or E) unit sitting
on the turntable. Beautiful paint scheme.
Are those Brazilian RR colors?

Don


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## rva1945 (Feb 11, 2016)

wvgca said:


> forgot to ask before, but is it indexed where it stops on the track automatically ?? or just rotation as long as you hold the button down ?


It is indexed in 12 degrees steps (75 steps from the stepper motor, 2250 steps for a 360 degrees turn in the gearbox). And I can fine position in 1 step it if necessary, and it has a 180 degrees turn.


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## rva1945 (Feb 11, 2016)

DonR said:


> A very interesting project very well done.
> 
> Really like that fantastic F (or E) unit sitting
> on the turntable. Beautiful paint scheme.
> ...


No they are D&RGW colors. It is a EMD F7 A unit, the black loco is a GP9.


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## rva1945 (Feb 11, 2016)

DonR said:


> A very interesting project very well done.
> 
> Really like that fantastic F (or E) unit sitting
> on the turntable. Beautiful paint scheme.
> ...


No they are D&RGW colors. It is a EMD F7 A unit, the black loco is a GP9.


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## rva1945 (Feb 11, 2016)

MichaelE said:


> Nicely done. Is it fabricated from metal or plastic? Looks like metal to me.


Well there is metal and plastic. The round rails and the handrails are of course metal, then it is mostly plastic.


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## Fire21 (Mar 9, 2014)

Very nice project! It runs smoothly and the engines don't derail...doesn't get any better than that! :appl:


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## tankist (Jun 11, 2009)

looking good :thumbsup:
was about to ask how you sensing/indexed it, but then realized its a servo so you can reprogram stops


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## rva1945 (Feb 11, 2016)

tankist said:


> looking good :thumbsup:
> was about to ask how you sensing/indexed it, but then realized its a servo so you can reprogram stops


No it is not a servo, it is a stepper motor, it gives more accuracy than a servo. Maybe a digital servo will do provided you send the appropriate pulse.


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## J.Albert1949 (Feb 3, 2018)

Very nicely done.
Good smooth movement from turntable to storage tracks.


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## Lemonhawk (Sep 24, 2013)

A little more info on the stepper indexing. Do you have the stepper connected by means of a gear train or is it direct you just use the step for the indexing?


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## PoppetFlatsRR (Jul 29, 2018)

Fantastic work.


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## rva1945 (Feb 11, 2016)

The stepper motor, as it can be seen in the album, is coupled to the TT by means of a gear train. The motor is a 48-step per revolution and it must do 2250 steps for a complete rev of the TT. So the total ratio is 2250/48.
And as the tracks are separated in 12 degrees angles, 360/12=30 positions. So the motor must do 2250/30=75 steps to align the TT to each track.


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## J.Albert1949 (Feb 3, 2018)

I took the time to review the OP's photo album of the turntable's construction here:
https://photos.app.goo.gl/F1mvqNDgwY8cKaPg8

Amazing job of engineering and execution.
Very innovative.
Looks great, works great!


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## sid (Mar 26, 2018)

WOW thats very interesting how you did that with a bucket. very smart thinking. man oh man you guys really do think out side the box. very cool.


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