I attended the Perth (WA) model railway show last weekend and picked up this neat little gearbox kit which I thought may offer an alternate solution for signal control.
Here is the pack on the right along with some other goodies I picked up too!
The parts are laid out here.
I then assembled the frames of the gearbox and inserted the motor.
One additional point to make is that I pre-tinned and soldered the motor drive wiring before assembly to avaoid theneed for having a hot soldering iron near the plastic framework.
The rods slide in and then you pick as many of the gears as you want to add depending on the reduction ratio your require. Each gear to pinion is a 4:1 ratio so two gears gives 16:1 and so on. Using all the gears as I have here has brought the final gear speed down to 2-3 RPM which is very slow and may well be close to the speed I need to drive signals. The company also offers a rack and pinion accessory that may well be ideal for converting the circular gear movement to linear drive.
The whole kit cost me a tenner (5GBP) which is great value however I feel that they may be a little noisy even when running of 1.5Volts as I did for this experiment (I used a AA battery). I will perservere with it though if for no other reason than to rule it out as being too noisy - the only issue I see as it is cheap and repeatable in it construction.
The company is based in the UK and is called MFA /
Como Drills. I would be pleased to hear from anyone who has used there rack and pinion set with a gear box or has another solution that may work. I am thinking about chopping some of the excess length of the main shaft and inserting it in one of the 4 aux holes shown in the gears as this would provide the linear movement possibly.