Grandad's wire

My grandfather spent most of his working life underground at Ollerton Colliery in Nottinghamshire.  One of the lesser known perks of the job was offcuts of detonator wire:  single core PVC coated wire in various colours.  He used to bring back carrier bags full of the stuff, and every layout that my father and I built in the 1970s and 1980s was wired with it.  He died in 1982, just a couple of years after retiring.  He was a lovely man, tall and solidly built with hands like shovels, and never an unkind word to say about anyone.  When I was eight or nine years old we used to go out by 'bus to Tuxford or Retford, and he would sit down and puff away at his pipe as we watched a succession of East Coast expresses thunder past. He was not a railway enthusiast but he encouraged my interest and always bought me a new model locomotive for Christmas. Alfred Silvester, 'Grampy', this blog post is dedicated to you.

Anyway, while I was hunting about for various electrical bits and pieces to wire up 'Belstone', I came across a tangled bundle of yellow wire.  Grandad's wire, the very last bit.  I cut it into three inch lengths, drilled lots of holes in the trackbed and soldered it to the rails in all the appropriate places.  Then it was just a question of turning the baseboard over and joining up all these wire 'droppers'.  I was going to give a blow by blow account of how I got the layout wired up and running, but that would probably lose me the few readers I have.  Layout wiring bores me, and will probably bore you too.

Also, even though the wiring is now in place and everything works, I'm not happy with it.  Messy, vulnerable to damage and difficult to trace faults.  I used a load of bits of wire salvaged from my last layout, which made it difficult to use any kind of colour coding, and the wire itself was rubbish (unlike Grandad's wire).  So at some point I will probably redo it, this time using thick copper wire busbars running the full length of the board - track positive and negative, and common returns for point motors and uncouplers.

Belstone rolls over to have its tummy tickled.  See what I mean about messy?

Most of the wiring was straightforward, following the basic rule for live frog points - always feed power to the toe of the point, never the heel.  DCC purists will argue that my wiring is all wrong, since most of the track sections are only 'live' if the points controlling them are set correctly.  But the ability to derail locos by running them against incorrectly set points is a feature of DCC that I can probably live without, and as I will not be having lights or sound in any of my locos I don't need them to be constantly receiving a DCC signal anyway.

The only really tricky bit was the live frog diamond crossing.  The instructions recommend using a DPDT toggle switch to feed power to the frogs, but I wanted to see if frog switching could be done automatically, and anyway it was late on Monday evening and I didn't have a DPDT toggle switch.  So I hit upon the idea of treating the diamond as two 'virtual points' back to back, and switching the frogs using a couple of SEEP point motors with built-in SPDT switches, the same motors that I used for the rest of the pointwork. Very Heath Robinson, but my 'Frankenstein switch' works just fine.  The motors are electrically linked to the point motor for one of the siding approach roads.  I have since looked into doing the same thing more neatly with relays, and found a double-coil DPDT self-latching relay that should do the same job.

The Frankenstein Switch - two point motors bolted together back to back

The big question - does it run?  Oh yes. Beautifully.  I did about an hour of testing with the J39, played about with the various CV settings on the DCC system, and I now have the kind of reliable slow running that I have never achieved before in 'N' gauge.  This is a great relief:  Belstone is, as I have said, all about shunting, which means reliable slow speed operation is critical.  I am now a True DCC Believer, but will try to avoid boring others on the subject.

What next?  I only have one loco, coupling issues mean I can't yet operate trains anyway, and the fiddle yard is still in storage forty mile away.  So my next post will be about scenery. Probably.