Model Railway Laboratory

Lately I've been beavering away on a project to add wireless remote control to some of my trains. It is a fairly complex project, the hope though is that by having wireless controllers in each loco, with a battery on board, I can alleviate a few pet modelling peeves of mine:

Unreliable running on dirty track, uneven track, dusty track, track that hasn't been cleaned in the last 30 seconds... in short, anything that Isambard Kingdom Brunel himself hasn't laid! Costly DCC decoders; DCC decoders that I can't reprogram or tweak to suit my needs; DCC decoders that only have 1 way communication; Inability to mix DC and DCC on the same track; Poor slow speed running, on both DCC and DC.

So nothing too complex!! We'll see how far I get.

As part of this, I need a way of testing my code. My day job involves writing a lot of code, and writing a lot of code to test my code. Luckily for that we ha...

A toolbox

Mrs A is very generous. She happily lets me spread my tools and projects out all over the coffee table with nary a complaint. On two conditions: as long as there is a space for her tea cup, and whenever we are having guests over, I release the coffee table from it's workshop duties.

It occurred to me during one of these tidying jobs that I spend a lot of time gathering up my tools and carrying them back to the train room. What I needed was a toolbox.

So I tried out a few ideas, asked google for some inspiration, thought about laser cutting something, etc etc, but in the end I just put all my tools on a piece of paper and rearranged them till they were nicely grouped. Then I took the measurements, drew up a quick plan and headed out to the garage.

I chopped up a few bits of pine, ply, and MDF and after a bit of planing, and a bit of sanding, I came up with this:

Fun with lasers - pallets

Something lasers are very good at is cutting out fine details. I've been trying a few little experiments to see what I can and can't do. One fun little project was to make up some pallets:

These are straight off the laser with no paint, though the singed look is remarkably realistic, and the dark edges give them good depth. These are made as a lamination of two pieces of cardboard; thicker card for the base, and thinner card for the top. Simply take the two squares, glue them at right angles, then once dry use a sharp knife to cut along half-etched cutting guides. Four cuts later and you a perfect shipping pallet.

Breda LRV - Body, bogies and chassis

I can't remember the reason, but a while back I decided to make a model of a Breda LRV, from the San Francisco Muni light rail network. I rode on one of these when I first visited America, from underground out to the beach. They are an interesting vehicle, running on both underground subway-style lines, and running on the street.

So they have unusual features for a train, like indicators and side mirrors. They also have a high level floor for subway platforms, yet once they emerge into daylight and start running on the street, steps down to street level magically appear inside the doors.

Useful links

A selection of the blogs that I enjoy browsing.

30 Squares of Ontario: E. L. Moore discussion and research, along with a great HO scale streetcar railway. Quinntopia: Currently on holiday, but lots of useful info about building a bustling city scene in N scale. Diotown: Hundreds of useful articles on all sorts of Japanese modelling. N Naro Struggles: Lots of small locos, trams, engines, carriages, rail motors, etc. Shochan's DIY: Chassis modifications, subway tunnels, building hacks, etc. Model Railroad Armchair Theory (Barrack Model): A master of reassembling deconstructed chassis with new slower gearing. Makes very small N scale...

Driving many outputs with Arduino C/MRI

A fun little side project of mine is Arduino C/MRI, a library that lets you easily connect your Arduino projects up to the JMRI layout control software, by pretending to be a piece of C/MRI hardware. Hence the name.

Hello World

The basic "hello world" example is fairly straightforward, wiring up a JMRI light to a physical LED on the Arduino board.

#include <cmri.h> CMRI cmri; void setup() { Serial.begin(9600); // make sure this matches your speed set in JMRI pinMode(13, OUTPUT); } void loop() { // 1: main processing node of cmri library cmri.process(); // 2: update output. Reads bit 0 and sets the LED to this digitalWrite(13, cmri.get_bit(0)); }

It's easy enough to extend this example to handle 5, 10, even 15 outputs... if you have an Arduino Mega, you could have a LED on...