Model Railroading > Foot-pedal rheostat to control trains?

Hello, all!

This might be one of the stranger questions asked on this forum, but... would anyone know if it's possible to use a foot-pedal rheostat (such as you might find for a sewing machine or power tool) as a model-railroad throttle? In theory, it seems to me that it could work, but I'd wonder whether you;d get any genuine speed control given the low-voltage of a model railroad...

A bit of background for the question: I'm a "third generation" model railroader and railfan, brought into it through my grandfather, father and uncle. My uncle has had ALS (Lou Gehrig's disease) for two years now, and is now confined largely to a wheelchair, with mobility left only in his feet and legs. So, I've had the crazy thought that it might lift his spirits this Christmas season to once again set up a layout at his house, and ideally find a way for him to be able to control it, with his feet and from his wheelchair. It probably wouldn't be much like my permanent layouts -- likely just a couple loops of tinplate on a table -- but it could be something. But not surprisingly, I've never considered designing even a temporary pike that you can run without hands -- a new challenge, indeed!

Thanks for any insight or advice!
Robbie Ketcham
Defiance, OH

It doesn't sound unusual at all. I'll bet a look in the Model Railroader magazine index would turn something up.



Edited 1 time(s). Last edit at 10/30/14 01:54 by wabash2800.

You can definitely do this.

I would suggest looking at sewing machine foot pedals or guitar volume pedals.

There are a couple of approaches;

Wire the existing pedal with a small a mount of circuitry to create the resistance needed to smoothly run through the range, or

Find a duplicate potentiometer to the one in your controller and install it in a pedal housing, transfer the wiring harness to the pedal.

Older pedals use a string (so to speak) wrapped around the potentiometer shaft to 'spin' it up and down as the pedal moves, very simplistic. Others used a rod or gear to move it.


I would look at an Ernie Ball volume pedal as one choice because the front is open, that will give you options.

Joel Brazy
Coatesville, PA

Foot pedal rheostats have been used to control other devices with motor speed, so it seems logical you can make that work if you like. No rules against it!

Cheers, Jim Fitch

The downside is that you would have to control everything from one location and probably be seated. I prefer handheld throttles that let me move around the layout plus give much finer control than a foot pedal.

Bill Deaver
Tehachapi, CA

MojaveBill Wrote:
-------------------------------------------------------
> The downside is that you would have to control
> everything from one location and probably be
> seated. I prefer handheld throttles that let me
> move around the layout plus give much finer
> control than a foot pedal.

Me too, but (gentle reminder) the context of this topic was to provide a control method to someone confined to a wheel chair.

On a similar vein, I had read some years ago that Neil Young bought a portion of Lionel Trains back in 1992 and was involved with the invention of controls - I recall he had a handicapped child?

Cheers, Jim Fitch

Many years ago I was a member of a club that had several home built throttles. Train speed was controlled by varying the input voltage to the transformer. This was operated by hand, but the concept should work using a foot pedal apparatus.

Something along the line of what you are describing, I think...

At one time, Dremel offered an item that matches what you are interested in.

Dremel #217 Speed Control. It was rated at 5 amps, not sure if that would be enough to run a DC powerpack or not.

Not a current production item, but it might be possible to find a used one.

Micromark may have something similar or possibly Harbor Freight or similar vendor.

Hope this is of some help.

And good luck on your quest.

Bob

Thanks for the ideas. Never thought I'd start shopping for a sewing machine pedal, but model railroad "innovation" can indeed take you to new areas!

Posted from iPhone

robbie Wrote:
-------------------------------------------------------
> Thanks for the ideas. Never thought I'd start
> shopping for a sewing machine pedal, but model
> railroad "innovation" can indeed take you to new
> areas!
>
> Posted from iPhone


I think its great you are doing something for a person to enhance there life as anything makes the day go by easier for them. Good luck.