Friday, 30 August 2013

A little more catching up...

A little more of what I've been up to...


The last progress report on the Y14 was that the chassis had been dismantled, and the wheels repainted and lined. Now it is time to start putting things back together. First, I decided to make the pick-up mounting plates demountable :-)

This requires soldering some captive nuts to the frame spacers for them to be mounted on:

The painted coupling rods can also be seen in the background. Together with brass ends to them, they look very smart. Or they will do until they are weathered into a proper working condition.

This is the chassis back together:

The DCC chip will slide into the smokebox, followed by the motor itself as it did when it was running on DC.

I can't remember what gauge guitar string I used for the original CSB wires. This time it's 14 gauge, which initial tests by the push of a finger indicate is not too far away from the truth. This time around, I've started a document on the computer to list the CSB wire weights used in all of my future locomotives...

The next step will be to fashion some pick-ups and solder them in place. Then I can see if it is a smoother runner than before I dismantled it!


Tuesday, 13 August 2013

In passing...

...I mentioned the weathering that needs to be finished.  I realise that I haven't posted any pictures showing the current state of this.

The initial rather raw body colour has had a first coat of black wash over it, to bring up the detail.  It has also nicely toned down the brick red to a much more workaday colour.  This is actually now very similar to the prototype colour photo that I have been working from.  This is of an industrial saddle tank locomotive, working in an ironstone quarry.

At this point I'm happy with the basic colouring, and the next step is to work up all of the detailed weathering of different types of oil mark, rust, coal, etc, etc.  Plenty of reference photos will be called into play for this as well.

However in the meantime I'll be re-fitting the driving wheels to my Y14.  They've just had the red lining applied around the rim.  I was going to leave it off, and go for a road-dirt filthy look to cover the absence of the lining.  I changed my mind :-)

I must polish the ultramarine paint from the treads first though.  A much easier job to do with the wheels off the loco than on it.


A quart in a pint-pot

That's what it felt like after making the decision to change from DC to DCC control...

As I have a liking for small locomotives, fitting a DCC chip will always be a challenge, and even more so when the locomotive is virtually finished.  You may recall that my little L&Y Dapol Pug has transformed itself into an industrial locomotive (with the aid of a coat of brick-red paint) and was waiting only nameplates and a final weathering.

As befits this very ingeniously designed kit from High Level, the innards of the model are entirely packed with motor.  Additionally, due to the way that the build goes together, access to much of it is difficult without doing a partial "unbuild" to reach the interior components.  On the plus side, at least I had successfully wired up the loco for DC operation and knew that it ran reliably.  This is how the underside looked in DC mode:

There's not a huge amount of room in there to fit any type of DCC chip...

Fortunately help was at hand from other Scalefour Society members.  When I visited the Norfolk and Suffolk Area Group a couple of weeks ago, I took the Pug along with me.  I was helped enormously by NSAG member and DCC guru Nigel Cliffe who was present.  As he spends much time putting DCC into 2mm finescale locomotives, then the Pug gave acres of room in comparison.

Nigel suggested taking out one of the spacers used to mount the pickups and slipping a small DCC chip in under that.  His initial recommendation was for a CT DCX75, which is small enough to slip into the space.  I promptly ordered a couple of these.

I started work on the DCC conversion by taking out both of the spacers to make room for the chip to go in.  Because of the presence of the end of the compensation beam and various fixing screws, I couldn't quite slip the chip in under just one spacer.  However it did fit very neatly in place between the frames when both old spacers were removed:

To avoid any possible shorts, the chip itself has been wrapped in some plastic masking tape.  It's the little red package that has tucked neatly under the end of the compensation beam.  To make sure that it didn't dislodge when the Pug is in use, I used the tiniest amount of superglue to fix one end in place.  The thick red and black wires are the original ones to the motor from its DC days.  The very thin grey and orange wires that are just visible are the ones from the DCC chip to the motor.  These have been soldered to the motor wires (after cleaning up the old soldering gunk on the ends...) and covered in heatshrink tube.
I then installed the  replacement spacer to mount the pickups on.  This was slightly wider than the original ones, and was located centrally between the wheels.
I always have trouble with wires becoming detached whilst trying to solder pickups to the same piece of copper-clad, so I decided to create some positive location for these wires.  Using a fine drill (size didn't really matter in this case...) I drilled two small holes to take the ends of the red and black DCC wires.
The ends of the wires were then inserted to hold them in the correct place, and soldered securely.
From here it was just in to the home straight, which unfortunately for me always is a long and painful one...  I really am no good at fitting pickups on locomotives!  I can just about manage it, but they are a bit hit-and-miss.  The next "clean" build that I start on a locomotive is going to be and experiment with split frame collection...

With the aid of fine-nosed pliers, and a lot of patience, I designed and made the pair of three-dimensional wires that can be seen here.  They seem to fit well, and work effectively so far.

And that was it.  A successful DC to DCC conversion.  I hauled out my ZTC controller, connected it to six inches of test track and the Pug moved under its own steam.  It's a little jerky, which I think is the pickups needing to bed in.  The motor or wheels have not been touched during the conversion, so I shouldn't have disturbed those.  It could really do with a few minutes running on a circular test-track to loosen it up.  I'll have to see what sort of opportunity offers itself.

Many thanks to Nigel for all of his advice and confidence that this could be done.  Now to finish the weathering and put it safely to bed.


Monday, 12 August 2013

Getting it all right...

Sounds familiar to you? 

Well, there's been something that has been nagging away at me ever since the GER tram locomotive was finished.  The Great Eastern experts that I know have been good enough not to point the error out to me, for which I thank them for avoiding relentless leg-pulling.  However SomethingHadToBeDone and last night I put the world to rights.

This is the locomotive as I previously left it:

And this is it this morning:
When I originally painted it, I was also painting the nameplates for my industrial Pug at the same time.  So I sploshed some black paint into the Y6's number plates, polished them back, and carried on with the weathering...  Forgetting until it was all finished that GER number plates are distinctively red as a background, and not black.
Of course, as all of the reference photos that I work from are in black and white, I didn't twig to it as I was going along...
Anyway, all it took to put matters right was some careful puddling of buffer beam vermillion into the plates last night and then leaving it overnight to set hard.  This morning, with the paint safely dry, I used a couple of small sanding blocks, first at 3200 grade, then at 4000 grade, to polish the paint from the brass and allow it to stand out.
Then of course the number plates stood out like a sore thumb (struck by a particularly large hammer...) compared to the weathered finish of the rest of the locomotive, so I used the same Citadel Miniatures black wash to tone them down slightly.
It's only a small change, but I'm really pleased with how it looks.  I now actually can declare the locomotive "finished"...