Planning a new train room
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The big picture: Update 26th April 2004
Having a lazy weekend saw me finally screw the flat baseboards to the false floor. In reality all they are are plain sheets of craftwood painted both sides. Since all wiring will be above the baseboard, I required this to keep the height down as low as possible.

On the Saturday I did some 1:1 planning with centerline instrument, tape measure and pencil. I drew on the boards the centerlines and point locations for the most inaccessible model. I detrermined I needed a curved point, and went to a hobby shop to purchase it so not to stop progress. Unfortunatly I then went out for the night.

On the Sunday I then plotted int he new point and then tried some experimental point clamps - ie small screws with a washer. MY idea is to use these to hold down the points - no gluing. Seemed to work, the head of the screw does not sit above railheight. So I put in one point with this method. Then I unscrewd it and then proceeded to cut a trench for a throw wire, the points sitting above like everything else will be situated about 7 inches from the point, the throwrod must go under 3 other tracks. Then I rescrewed it down.

Wiring will also need to go down a trench. So I decided to plan the module online, and you can see the diagram below.

You may note I haven't shown the wiring for the points. It is still to be determined, see below.

Point Motor Specs

I also decided to try an initial point motor spec sheet:



The premise is to reuse old Floppy disk drives as Point motors. So far Simon Kolpala has been busy drawing up designs. But here is what I think:

The Point motor should be useable by anyone. I would like to see it replace the PMG telephone relay as a cheap alternititive to the RTR ones. But I can see not everyone will want to use it directly with a computer, or DCC. So the unit should work as a standalone device.

This project is very much still in paper design stage, so there is alot to work out. The final design may include ideas off the advanced idea shown below.

I have two options in mind. The Advanced and Basic one.

The Basic Concept:

A Description of the point motor's input/outputs:
  • - & + = to power the unit. I am not sure what power supply will be needed
  • Input A = is used for telling the circuit a change of state.
  • Input B = is used for telling the circuit a change of state.
  • COMMON AB = the power (or ground) common to all inputs.
  • NC NO CO = normal relay like connecter for use for acessories.
Also you could have thise config jumper onboard:
  • Input A only = This allowa a simple 2 wire to a on/off switch, ie ignores input B & C.
Travel would be based on the auto trvel idea as per the advanced option.

The Advanced Concept:

A Description of the point motor's input/outputs:
  • - & + = to power the unit. I am not sure what power supply will be needed
  • Input A = is used for telling the circuit a change of state.
  • Input B = is used for telling the circuit a change of state.
  • Input C = is used for telling the circuit a change of state.
  • COMMON ABC = the power (or ground) common to all inputs.
  • NC NO CO = normal relay like connecter for use for acessories.
  • NC2 NO2 CO2 = normal relay like connecter for use for point motor frog polarity.
Also you could have these config jumpers onboard:
  • Input A only = This allowa a simple 2 wire to a on/off switch, ie ignores input B & C.
  • Speed = Allows for a low speed or a higher speed of moving the point motor. This can be useful if you want the point to simulate a real motorised point, or a hand pulled point.
  • Point/Signal = means it may use some "bounce" moving between positions.
  • 2 pos / 3 pos = to use all three inputs for a 3pos semaphore signal
  • Constent move = allows it to be used as a animation device that constently moves back & forward. In this mode the travel parameters are used for time ( ie 2mm = 2seconds), and the motor will move the full extent ( 20mm ).
The Travel parapmeter will allow: (you can only select 1 option from this area)
  • Auto Travel= advanced option to move the point motor until it encounters load then stops, in each direction.

    The rest of the options are just the travel allowed
  • 2mm
  • 3mm
  • 5mm
  • 10mm
  • 20mm








That's all for now.

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