Switchmaster turnout motors

[mike_lawyer]

So in my search for a good turnout motor for use under 3 inch foam, I have come to the realization that I need a motor that has a circular sweep, rather than one with a linear sweep like a Tortoise has.  This would seem desireable when using a piano wire and tube method like I would like to use.

In scanning the Web, I came across Switchmaster motors that look perfect for this application.  However, the company that sells the Switchmaster line appears out of business.  Switchmaster uses Hankscraft 3440 series motors for this application.  Does anyone know of a supplier of these motors?  Also, does anyone have any experience with Switchmaster motors for use on turnouts?

[Maletrain]

The N scale layout at my club uses servos for turning wires in tubes to throw turnouts.  Tam Valley has an extensive line of servo controllers, including add-on decoders for their boards.  See https://www.tamvalleydepot.com/

[mike_lawyer]

Thanks for the info, I kind of want to stay away from servo motors, as they have to be programmed and such.  I would rather have a straight DC motor that I can control with a simple DPDT switch.

[Narlie]

Builders in scale website seems to be kaput. They say they are closed ???

[mark.hinds]

That looks like what I am using on my layout.  https://www.therailwire.net/forum/index.php?topic=28831.msg305681#msg305681 

Mine were purchased back in the 80s (I think) from "Electroplumbing" "American Switch & Signal Div.".  Their literature specifically refers to "Switchmaster" motors.  Address was 1918 Parklane Ave.  McHenry, IL 60050. 

Along with the Switchmaster display motors, I also purchased the same company's "MD-1" motor drivers.  These were custom PC boards, each of which controlled 4 motors, and "... the switch motor drivers allow these low power motors to be operated as though they were twin coil switch machines, since the outputs are maintained after the inputs are removed".  I use a diode matrix push-button control scheme as inputs to the MD-1s. 

Physically, the motors are clamped sideways under the sub-roadbed, aligned with the Turnout above.  They connect with the turnout using a stiff steel wire.  Pressure (which can be a lot) is reduced by wiring a resistor in series with the motor.  If the turnout needs power routing, I have to implement it using separate momentary contacts activated by the aforementioned steel wire, which is a disadvantage over Tortoises.  I could probably take detailed pictures of the installation if you are interested. 

MH

[mike_lawyer]

Hi Mark, thanks for the response.  Those are definitely the motors I am thinking of purchasing.  There are a few YouTube videos of guys using them on their layouts.  The key I am looking for is where to purchase them.  The main website appears to no longer be in business.  If anyone has a source for these motors let me know.

As far as frog powering, I have a slew of triple throw switches, I figure I could use one of the throws on the switch to control frog polarity.along with motor control.

[mark.hinds]

Internet search of "REBCO" motors (one of the types referred to in the American Switch and Signal documentation from my original reply) yielded a page from a Kalmbach wiring book, showing the same type of motor, which they labeled "American Switch and Signal (Hankscraft display motor)".  So following up on the latter yielded this website:  https://www.hankscraft.com/customizable-motors/

The black plastic casing on an actual 80s-era motor from my layout says "187 / 12 V / 2 RPM / Hankscraft Motors, Reedsburg, WI", and it's about 1.8" in diameter, which suggests a similarity to the model 3440 on the above web page.  One difference is that the product I purchased from AS&S has a transverse hole drilled through the motor shaft near the end, to allow the insertion of a control wire.  I don't see such a hole on the 3440, so you'd have to figure out a work-around for that.  Still, it looks promising...

MH

[u18b]

I used to own one of these. It may still be hidden somewhere.

I liked it, but as I recall, the torque pressure is a bit strong for N.
Especially if you will use hand laid turnouts.

You will want to experiment before laying out a lot of money.

[mark.hinds]

I used to own one of these. It may still be hidden somewhere.

I liked it, but as I recall, the torque pressure is a bit strong for N.
Especially if you will use hand laid turnouts.

You will want to experiment before laying out a lot of money.

You can control the torque by putting a resistor in series with the motor.  They suggest 1K, but I think I'm using 1.2K.  You could use other values of course, based on, as you suggest, experiment with the turnouts used.  Probably put as many PC board ties as you can in your hand-laid turnouts, to maximize strength, and also use silver solder, per Robert. 

MH

[nkalanaga]

Besides using extra PC ties, one can also use "rail braces", like the prototype.  In my case, I drilled through the ties in the point area, and put actual spikes in  them.  The stock rails can move! 

Just don't forget to gap the underside of the ties, if using double-sided PC board.

[Maletrain]

After reading all this about what is needed to set up these motors, using servos seems a lot easier and less likely to cause trouble.  Setting the servos for pressure of the points on the rails is done with a plug-in electronic adjustment device that seems much simpler to operate than soldering a selection of resistors into power feeds. And the servos are readily available and relatively inexpensive. So, I am not seeing the attraction for these motors.

[mark.hinds]

After reading all this about what is needed to set up these motors, using servos seems a lot easier and less likely to cause trouble.  Setting the servos for pressure of the points on the rails is done with a plug-in electronic adjustment device that seems much simpler to operate than soldering a selection of resistors into power feeds. And the servos are readily available and relatively inexpensive. So, I am not seeing the attraction for these motors.

You use the same value resistor for all turnouts (based on experiments with the first one), and you have to solder to the motor leads anyway, so it's just one more solder joint.  I haven't found it to be an issue, FWIW.  My main issue is the lack of auxiliary contacts. 

Thinking about the pressure issue further, the weak point in a hand-laid turnout would appear to be the joint between the points and the throw bar (I have little experience with hand-laid turnouts, having only made one so far, and it's not installed).  The Shinohara code 70 turnouts currently used on my layout have a metal reinforcement running between the points, along the top of the throw bar; however, that connects the 2 points electrically.  So some sort of S-shaped mechanical reinforcement soldered to the inside of each of the points, increasing the surface area of the solder joints?

[rodsup9000]

Hi Mark, thanks for the response.  Those are definitely the motors I am thinking of purchasing.  There are a few YouTube videos of guys using them on their layouts.  The key I am looking for is where to purchase them.  The main website appears to no longer be in business.  If anyone has a source for these motors let me know.

As far as frog powering, I have a slew of triple throw switches, I figure I could use one of the throws on the switch to control frog polarity.along with motor control.

Mike,
 I have several Switch Master's and they are very overpowering for N scale turnouts.

 Using Tam Valley's Octopus III with servos does not require any programing at all. Can be used with toggle or push button switches and is cost effective.
https://www.tamvalleydepot.com/products/octopusservodriver.html

[mike_lawyer]

I was able to find a couple of these motors and ordered them just to test.  I would think increasing the resistor size would be sufficient to reduce torque, correct?

[mark.hinds]

I was able to find a couple of these motors and ordered them just to test.  I would think increasing the resistor size would be sufficient to reduce torque, correct?

That's what I remember from over 30 years ago (you will note my frequent 1980s references above).  Looking at the layout this morning, I'm using the recommended 1K for the pressure I wanted with my N-scale Shinohara turnouts, but I vaguely remember experimenting with larger resistors, such as 1.2 and 1.5K.  The instructions say "If the motor is not driven by the MD-1 motor driver circuits," (mine are, but I used the resistor anyway for some reason) "place a 1000 ohm resistor in series with the motor to limit the stall torque.  This is to prevent the possibility of pushing the stock rails off the railroad."  So since you've bought some already, next step would be to experiment with different resistors (say, 1K, 1.2K, 1.5K, etc.) to see if they do what you want. 

Edit:  N-scale Shinohara turnouts power the frog through the points, so for reliability, I wanted a fair amount of pressure.  In 35 years, nothing has given way except once, and that was a solder joint on the actuating wire, where I soldered a thin wire to the normal thick one, in order to allow penetration of the smaller-diameter grommet in the throw bar on the Shinohara double slip switches.