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SwitchMaster premium slow-action switch machines employ fine-quality powerful gearhead motors from Hankscraft.

Installation Options

Wiring schematics and instructions sheets are provided with each SwitchMaster switch machine and accessory. They and additional information are posted here for your convienance.

These and ALL materials posted and printed ARE COPYRIGHT Builders In Scale / SwitchMaster © 2003-2009.
They may be copied for NON-COMMERCIAL USE only.


SwitchMasters are powerful and have lots of throw. They can transmit their power through thick or thin roadbed, through mechanical linkage such as push-pull rods, cables, bell cranks or whatever is needed to reach that impossible location. We are forever in the process of developing this section with more information, photos and examples.

SwitchMaster switch machine isometric photo of installation.

HORIZONTAL MOUNTING of SwitchMaster Switch Machine

When space under your roadbed is an issue an alternative to the standard vertical mounting of our SwitchMaster switch machines is to mount them horizontally. Vertical mounting requires 3 of space while horizontal mounting requires 2. If less space is available then mount them remotely with the turnouts operated through mechanical push rods, cranks, cables or a combination there of. SwitchMasters have plenty of power and length of throw to do the job.

To mount them horizontally a 3 long 1-1/2 (or larger) aluminum angle bracket is recommended. Pipe clamps can be used however finding one the right size can be difficult as the motor body is slightly tapered and an odd size (just over 1-3/4). The angle bracket is a great answer and readily available at your local hardware.

Cut to 3 length and mark the locations for the motor mounting holes: one 0.375 (3/8) centered to clear the shank hub, and two 0.125 (1/8) inline with it to match the motor mounting holes on the tabs. These are just slightly over two inches apart so drill the center hole first, mount the motor and trace their locations. Make sure you mount the motor high enough to clear the angle that is tucked under the motor, so center about 1.125 (1-1/8) high. Drill two more 0.125 (1/8) holes or whatever size is needed to clear your mounting screws (1/2 to 1 long round heads) in the base. Use two 2-56 x 1/2 machine nuts & bolts to mount the motor.

Horizontal mounting also provides an opportunity of hiding direct linkage to the throwbar. By cutting a slot (~1/4 wide, 1/2 long) directly under the throwbar the connection can be completely concealed without any non-prototype activating hook topside as with the standard installation. Of course you do need to cut the slot before installing your turnout as this would be very difficult afterwards.

We'll use the provided .032 (1/32) x 5 crank wire and 1/16 x 1 brass sleeve to make the connection, soldering them together (wire inside tube) and inside the hole in the motor shaft, with one end long enough to engage the throwbar through the slot in your roadbed.

Use .047 (3/64) music wire for larger scales and/or greater distance.

To make installation easier the end of the crank wire can be tapered on a grinding wheel, allowing it to find the hole in the throwbar more easily, cutting off the excess after installation. Remember, music wire is quite hard so you must use the right tools. Don't ruin your good soft-wire cutter! Use a Dremel cut-off grinding disk.

Mount the motor so the shaft is inline with the turnout, the wire straight up, and the points midway. With everything centered no additional fine-tuning is necessary but mount the bracket with one screw, test, then lock it down with the other screw.

SwitchMaster switch machine horizontal mount installation.



In some situations you may not have any clearance under your turnout. If moving the turnout is not an option consider using push rods and tubes with the switch machine motor off to the side, or use same with a bell crank to move it down the track or in any direction for that matter.


Brass tubes and 0.032 (1/32) music wire can be used to transfer the motion of the motor to the throwbar over some distance. Use .047 (3/64) music wire for larger scales and/or greater distance. The wire is connected to the motor arm loop on one end (the motor can be mounted either way) bending 90 degrees and travels through 1/16 brass tube(s) (they can be short sections or continuous) and turning up through the slot (as explained in Horizontal Mounting) where it engages the throwbar. Simply use hot glue to attach the tubes to the bottom of your roadbed.

The motor may be mounted either way employing the standard motor arm loop.


If you do not have any space off to the side we won't scold you for poorly designing your trackwork (though tempting), instead we'll explain how to use a bell crank.

A simple bell crank can be employed to make a turn, 90 degrees or any angle for that matter. For simplicity's sake let's describe the right turn. As we just described for tubes and wire, let's add a bell crank to the motor end. Take the motor away for a moment. That wire moves back and forth. As it does it moves the throwbar. Mark the center point of the throw. Draw a square line from that center point. Measure 1 down the line. This will be the swivel point of our 1 bell crank. Now measure 1 over and mark the center point of the new leg of tubes and wire, with the motor moved to the far end of them. Commercial bell cranks are available for model airplanes. Or you can build one out of brass stock. They need to swivel freely as do the wire ends, but without disengaging (bend over the wire ends).

There may be some looseness to over come. No problem, SwitchMaster's have plenty of strength and throw. Since the motor arm swings in an arc you can employ leverage: a shorter motor arm is stronger, a longer motor arm is weaker (still plenty strong) has greater range of motion (is 2-3 enough?). Employing leverage can be done on the bell crank too: setting the motor connection closer to the swivel will amplify the motion or setting it further will diminish it. Remember, the motor is going to turn until it encounters opposition and stalls out. It doesn't care if that is 1 or 1/4. So it automatically takes up the slack.


If you have no side space to work with and cannot go down (who put those darn hidden tracks there anyway) you can build a direct link bell crank, that is one that has the activating wire attached firmly (soldered) to the bell crank itself. In this case it sticks straight up and engages the throwbar. The other end is connected to the remote motor with the push pull wire and tubes. The bell crank can be built out of brass stock available from K&S Engineering at your local hobby shop.

SwitchMaster switch machine installation.



While you are at the hobby shop looking at model airplane parts take a look at the flexible control cables. These could be used to transmit the throw motion in up, down and around if you don't have any straight lines to work with. While in this Rube Goldberg mood think about other mechanical means that you could transfer the motion. Stretch the bell crank out and make a pendulum out of it. It doesn't have to be straight either so long as it is stiff and can transmit the motion. Nor does it have to be horizontal. The ideas go on and on. One of them should solve your problem.


All of these installation methods will work on thick or thin roadbeds. On foam-type roadbeds we recommend mounting the motors and linkage on plywood else they may tear away. For instance we hot glued 3 wide 1/4 plywood strips under 2 foam roadbed and installed push-pull wires, tubes and machine on top on our Apple Valley display layout.


SwitchMaster logo.


SwitchMaster logo.

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