Thursday 25 February 2010

LED Point indicator wiring

My intention is to have, on a mimic board, route indication driven by the points settings. Green indicates the route is set, and red means the route has points set against. So what is required is a switch on the point motor that will light a green LED when set in one direction, and will light a red LED when set the other way.

The solution, after a lot of googling is this. A microswitch is fixed to the bottom of the point motor. The COM tab is wired to the +ve feed of an ancient Triang uncontrolled DC power supply. The OFF tab is wired to one leg (anode) of a bicolour 3 legged red/green LED via a resistor, and back to the -ve terminal via the common cathode (centre leg). The ON tab is wired to the other leg (anode). This means that this LED will light green when the point is set "off" or normal, and red when switched. An identical LED is wired in the same way, in parallel, but the opposite way round, so it shows red when the point is set "off" or normal, and green when switched.

Here's a diagram:



And here are photos of the test wiring:


  
  
 


Notes:

I initially tried wiring with two-legged bicolour LEDs, but to get the desired effect requires extra diodes and other electronics stuff - so it's simpler to use the 3-legged versions. I used Maplins for the test but they are cheaper at All Components and Rapid.

I used a cheap microswitch (50p at Rapid, £2 at Maplins!) which will be glued to the bottom of each Peco PL10 motor. You could use Peco PL13s but they have a bad press, and they are much more expensive (£2.80-ish). Here's a photo:

Resistors: I used 680R metal film resistors from All Components, at 5p each. I could have used slightly lower resistance, perhaps 540R - there's a formula to work out the minimum resistance on Brian Lambert's site

Tuesday 16 February 2010

Wiring thoughts

Was directed to Brian Lambert's site via the N Gauge Yahoo! group. Brian's site is excellent, loads of detail and practical experience, clearly explained.

I need to think about wiring now, before laying track, as holes for dropper wires will have to drilled for wiring as track laying progresses, and I don't want to make it up as I go along.

From Brian's site, and other readings, here's my basic track wiring plan:

Use a bus architecture for the main rail power feeds. 'Bus' is a fancy word for cable, and it will run around the underside of the baseboard following (roughly) the track main line. Two wires are required (live and neutral) and I'll use the red and black wires from household electric mains cable (2.5mm twin core and earth).

I'll then drop wires from the rails at appropriate places. Probably I'll use the wire-soldered-to-rail-joiners method - easy to solder first and join later, rather than faff around with soldering to the outside (ugly) or underside (easy to melt sleepers) of the rail.

Dropper wires will then be connected (terminal blocks or soldered) to wires that will then run to the bus.

Point wiring can be considered separately, except when track polarity needs to be switched by a point motor. The only place I think this applies is the long crossing. Polarity of point frogs is switched automatically from the switch blade making contact with the stock rail. (I'm using Peco code 55 electrofrog points throughout.)

Questions:

Should I draw up a full wiring plan? Probably.

Do I want to wire the switch blades of points, or depend on contact with the stock rails? My inclination is to rely on the stock rails, as wiring up the point blades involves intricate soldering (with the risk of messing everything up).

At least I don't have to worry about isolated sections, as my DCC decision removes this requirement.

Tuesday 9 February 2010

Stove 'R's arrive!

Almost exactly one year ago the N Gauge Society announced that it was producing its first ready to run wagon - a Stove 'R'. As it was available in LMS livery (amongst several others) I paid my deposit for two like a good club member.

They arrived yesterday.

Worth the wait? Absolutely. They are splendid, great detail and (important) quite different to anything else you can get RTR in LMS.

According to the LMS Carriage Society (yes, there is one!) the Stove 'R' was "used on parcel, newspaper and milk trains, which often went attached to passenger trains." It was designated BGZ code in BR times, or CR in LMS days.

The N Gauge Society Stove 'R' was produced by Dapol. Produced in different running numbers in LMS livery: my wagons are 32975 and 32977.

Here are some photos:

  
  

These next two photos show the colour difference between the Stove R, produced by Dapol, and the Graham Farish Stanier coaches. Quite a difference and the roof colour is very light on the Stove R.
  
 



And the real thing is on the Bluebell Railway here.

Monday 8 February 2010

Southampton MRC show

Completely with an n gauge bias, I toddled off to Southampton last week to see New Mills, as featured in Railway Modeller in Sept 2009. It was splendid. No station, interestingly, but a main line and both steam and diesel shed/depot.

My pics are below, taken with my iPhone. A bit naff but okay. As there was something moving on the main lines pretty much all the time (a good thing!), there's a bit of blurring that a better camera would improve on. Must try harder...

 
  
 

Monday 1 February 2010

Conditioning Sundeala

As per the instructions, I've conditioned the Sundeala which will top my baseboards. Instructions come with the boards, which I got from Alton Model Centre, or are available on the web site.

First slosh a good half a litre on each board, on the reverse (which I've assumed to be the side with the Sundeala logo on).



 


Then stack them on top of each other, wet side to wet side, thus:




Finally, drop a couple of baseboards on top to keep everything flat and in place.




And wait 48 - 72 hours...