Monday, June 29, 2015

How I constructed a gunpowder van from a cheap trinket box

The Copper Mine would need a supply of explosives which, of course, would be transported on the railway. I decided it was about time the railway had a purpose-built gunpowder van.

After doing some research on the internet, I identified what looked like a promising prototypes, albeit on a narrower gauged railways.


 I happened across a small trinket-box in a well known High Street discount bookshop for the princely sum of £2.00 which looked like the promising basis for a 3' gauge representation.

On returning home, I checked its dimensions against a Hartland Loco Works wagon chassis and found the base of the box was exactly the same length as the chassis and only a few millimetres wider.

The hinges and latch were unscrewed from the box - I'm sure these will one day come in useful! The lid was glued to the other half of the box with PVA and then the box rubbed down with fine emery.

 1.5mm thick plasticard was marked out at 5mm intervals.......

...... and 3mm wide strips were cut from the sheet.

 After some experimentation with various superglues, I found that liquid poly solvent was the most effective at sticking the plasticard to the wooden box.

The box was used as a template and then marks were made 3mm in from the line......

....... before being cut out ........

...... before being glued to one end and vertical strips added to define the door.

 4mm wide strips were then added along the base of the box on the sides ......

 ..... and ends.

 3mm wide straps were then added to the 'doors'.

 and hinge plates were then cut (5mm wide, narrowing to 3mm, 15mm long and glued to the sides at the same height as the door straps.

 A piece of 3mm diameter plasticard tube was marked at 4mm intervals.......

 ..... and these pieces were then cut in half laterally to make the hoops for the door latch (which was also cut from a piece of 1.5mm thick plasticard) .......

..... and also the hinges for the door.

Cambrian Models rivet heads were then applied to the strips using liquid poly solvent.....

.... and filler applied to any cracks, screw-holes and crevices (in hindsight it would have been better to have done the filling before the strips were applied - easier to rub down).

A Cambrian bolt head was glued to the centre of the door catch to act as a pivot.

Once all the rivets had been applied, the body was given a couple of coats of Halford's grey primer from an aerosol rattle can.

Once dry, this was rubbed down  with fine emery......

..... and more filler applied to the remaining dints and depressions ......

 ...... before being rubbed down again.

The body was then given another couple of coats of primer, followed by two coats of satin black.

 The body was then screwed to the wagon chassis.........

..... and the wheels and couplings fitted.

She needs some lettering to be applied ..........

..... and also some light weathering to match the well-used look of the rest of the rolling stock.

...... bit she now makes a welcome addition to the line's rolling stock.

Friday, June 26, 2015

How I constructed a plate frame Simplex loco from an IP Engineering kit

Having recently decided to replace the Gn15 feeder line from the Copper Mines to the crusher and loading hoppers on the main railway with a 32mm gauge railway (see Progress Report 59), I realised I needed some rolling stock to operate it. I'd previously purchased a small freelance design battery powered diesel from eBay, which I modified to operate under radio control and it autoshuttle mode using a Deltang Rx65b receiver (see How I converted a small diesel to radio control and How I reprogrammed a Deltang Rx65b receiver to operate in shuttle mode). But I have always been attracted by the diminutive Simplex and Lister internal combustion engines. I figured that, as my railway is set in the early 1930s, it would be entirely feasible for the Bickerton Copper Mining Company to have invested in at least one Simplex loco following World War I. As a consequence, Santa brought me an IP Engineering Plate Frame Simplex kit which, for various reasons, had been sitting on my shelf for the past five months.


The motor unit

I decided to start with the motor unit, as I figured this might be the fiddliest component to construct - and if that didn't work properly then there would be no point in continuing the rest of the build.

The various components were checked ......

.... and then the worm gear was forced on to the motor shaft in the vice. I have found in the past this to be the most reliable way of fitting worm gears.

After checking that the motor still spun freely .......

.... the layshaft was threaded into the sub-chassis and one of the gear wheels was push-fitted on to it, so it was more or less central on the shaft.

 Two brass bushes were then threaded on to the ends of the shaft and superglued in place.

Wheels were then pushed on to one end of each axle and the axles inserted into their relevant holes. A gear wheel was threaded on to the rear axle and positioned to mesh with that on the layshaft. The other wheels were then pushed on to the ends of the axles and the motor was fixed in place with the two self tapping screws which were provided.

 At this point, I remembered the sprockets and Delrin chain which I had purchased and so, the wheels and axles were removed to enable the sprockets to be threaded on. The chassis was then reassembled.

The chain was then shortened to the length needed, by prising apart the links and then, the links were joined to make a chain loop around the sprockets.

The chassis bearers were then bolted to the ends of the chassis.

The body

I decided I would use 70 degree low-melt solder and a heat-adjustable soldering iron for the construction of the kit; something I have never used before. I am very glad I bit the bullet and ventured into this previously unknown territory, as the advantage of solder over glue is that the bond is almost instantaneous, and joints can be unstuck and rejoined with the re-application of the iron.

Following the detailed instructions, the four chassis members for the body were joined together. At the same time the fouling bar supports were soldered into the corners. This proved to be quite tricky and I almost reverted to epoxy resin, but I persevered and in the end discovered that 'tacking' worked well. The components were initially lightly tacked together with small blobs of solder which allowed for some fine adjustment. When everything was in the right place, the joints were flooded with solder.

Two brass plates were then lightly tacked into place and the axle supports fixed behind the apertures on each side.

The brass plates were then more permanently soldered.

The fouling bars were then fixed to the supports and their ends filed flat.

 The motor unit was then put into place and its two supports soldered to the underside of the body ......
 ..... making sure the wheels lined up with the axle supports.

The driver's seat was tackled next. The sides were attached to the seat-back.

And then the seat slats were fixed to the sides. I had to take great care with these as too much heat caused the very thin whitemetal material to melt. I turned the thermostat on the iron down as far as I could, and applied the solder-laden iron to the joints very quickly to the flux-painted slats. The spacing between the slats is not entirely even, but I think trying to re-solder these joints would be counter productive - anyway, a driver will be sitting on them and so they will probably not be seen anyway.

 The two mapping pins which are provided for the driver controls were trimmed and inserted into two 0.5mm diameter holes drilled one of the engine bearers. They were then fixed in place with some solder.

The clutch pedal was then soldered to the side of the engine bearer.

 A 1.5mm diameter hole was drilled vertically through the multi-height couplings.....

..... to take the coupling pins.

The couplings were then fixed to the buffer beams .......

 .... and the buffer plates soldered below them.

The four sand boxes were then attached to the corners of the chassis.

The brake standard and the seat were then attached to the rear of the chassis ......

.... and the brake wheel attached to the standard (again with the minimum of heat applied).

 The two end-pieces were then attached to the engine support beams...

..... and the engine covers first tacked and then soldered together.

 The outsides were then filed to ensure the match was as accurate as possible, though as these plates were supposed to be hinged at the centre to allow access to the engine, I felt the alignment did not have to be absolutely precise.

The ends of the engine covers were then attached....

..... followed by the lower sections of the covers. It looked like there would be a need for some judicious filling and sanding in these areas.

The engine cover assembly was then attached to the engine bearer assembly ......

.... and the engine cover was then attached to the chassis .......

 .... and the silencer/exhaust pipe attached ......

...... followed by the radiator and its associated pipework.

The sub-chassis was then attached and the switches bolted into their respective positions for a quick photo-shoot.

At this stage I did a re-appraisal. Comparing the 'finished' model with photos of the prototype (see below), I realised that a few compromises had been made and so, I decided to make some modifications to improve the model's appearance. With the benefit of hindsight, I should have considered these before embarking on the build as the modifications could have been made more easily during construction. However, not to be daunted, I pressed on.

Modifications and detailing

 In my travels (see my narrow gauge railways blog), I had the opportunity to get some pictures of some plate frame Simplex locos to help guide my detailing efforts. A visit to the Moseley Industrial Museum in Cornwall ........

..... and the Devon Railway Centre ......

..... provided me with some images which I could use to guide my detailing.

 One of the first things I noticed was that I had installed the pipework for the radiator and indeed the radiator itself the wrong way round. These items were re-positioned. I also removed the two slide-switch mountings from either side of the engine compartment.

Using my site photos, I fashioned representations of the engine as viewed through the sides of the engine compartment from various off-cuts of plasticard and Cambrian bolt heads.

 First one side .......

...... and then the other, were fixed into place.

A similar panel was fixed to the front of the engine compartment bonnet.

I then decided that the blacksmith at Bickerton Copper Mine would probably have created a cab for his fellow workers' protection. I researched various images on the internet and decided that some cabs fitted to various Simplex locos seemed to be freelance affairs. Using the dimensions of the driver's 'compartment', I cut out a front .......

..... and a back for the cab from 1.5mm thick plasticard and joined them together with some strips of plasticard.

 A roof was then fixed in place to hold everything together.

Cambrian rivet heads were then applied where seemed appropriate.

And then the cab was superglued to the engine compartment bonnet.

This was test-fitted to the chassis and a few minor amendments made. For example, at the front of the cab, the sides were extended down to the running plate as, although some pictures I found on the internet showed otherwise, I felt it looked better this way.

A small toolbox added to the front of the loco. Here you can also see the reversed radiator and revised pipework.

She now seemed a lot more complete and so attention was turned to sorting out the electrics.

Preparing for the electrics

After exploring various locations for the Deltang rx65b receiver/controller, I eventually decided it would be best placed inside the cab, rather than under the engine bonnet where the aerial would be shielded by the whitemetal casing. Rather than fixing it to the underside of the cab roof, I decided to make a side wall to the cab behind the driver's seat (as was the case with a lot of Simplex locos).

10mm wide 'planks' were cut from 1.5mm thick plasticard, sufficiently long to sit inside the cab framework. The edges of each plank were bevelled slightly with a craft knife and the faces scored with the teeth of a razor saw to simulate wood grain.

 The 'planks' were then glued into place behind the framework.

I wanted to add some bolt heads for apparently fixing the planks into place but nothing on the Cambrian sprues I had to hand looked small enough, and so I decided to produce my own. I made a strip of 1mm x 1mm plasticard (see How I Make my own microstrip) and then cut approximate 1mm cubes from this:

These were then carefully fixed into place with liquid poly solvent.

 The Deltang Rx65b was then test-fitted ........

..... and a scribed panel glued into place above it, making a double-walled cavity.

 Only at this point did I think about how the wires would be fed into the engine compartment. A couple of 3mm diameter holes were drilled through from the engine compartment to the cavity, and opened out to form a slot. With much effort the wires were then fed through. Of course, in hindsight, it would have been easier to have done this before the second wall was added.

A 15mm wide brass plate, with 30mm and 80mm diameter holes was soldered between the two flooring plates of the chassis - these would later accommodate the on/off switch and the charging socket.

Painting and weathering

At this point, I decided to paint the model. As I was intending to try a more sophisticated approach to weathering on this model, I gave the two halves a couple of coats of Halford's red primer from an aerosol rattle can.

While waiting 24 hours for the primer to harden off, I took a few photos .......

..... and tried to identify where some additional filling and rubbing down would be required.

 Filler (Squadron white putty) was applied to those areas which needed some attention, and then gently rubbed down with fine grit (1200 grade) wet and dry emery paper.

 It was at this point, I decided the flooring of the model didn't look quite right. On the Simplexes I had seen this was some form of chequerplate steel, and so some 1:25 scale double 'treadplate' embossed plasticard was purchased from Slaters. This was trimmed to size and glued to the floor plates front and rear.

 The model was then given another couple of light coats of primer......

 ..... and I felt vindicated in adding the extra detail to the flooring.

Probably doesn't make an enormous difference but I feel it looks better than the plain floor.

Having done some background research, I thought I'd try a different approach to simulating rust on this model. Humbrol rust colour was applied to areas which I felt would be more susceptible to rusting and, while the paint was still wet, I sprinkled crushed sea salt crystals on these areas.

Once the 'rust' paint had dried, the model was given a couple of coats of Halford's Rover Brooklands Green, my livery for locomotive stock on the railway.

Here we see the chassis after its first light coat of green livery.

The sub-chassis was given a couple of coats of grey primer and then a couple of coats of satin black.

Once the paint had been given around 24 hours to harden off, the salt granules were scrubbed off with warm water using an old toothbrush. The two halves of the model were then reassembled for another appraisal. At this point I decided to add a short length of heatshrink sleeving held in place with some copper wire to the top-hose of the radiator. The radiator and flooring plates were given coats of matt black acrylic and mucky brown/black acrylics were smeared into nooks, crannies and crevices before being wiped off.

I felt that my attempts to represent peeling paint had not been fully effective - ie the upper coat is supposed to peel away revealing the 'rust' beneath, the combination of peeling paint and what looks like rust bubbling underneath actually looked quite realistic.

Weathering powders were added to enhance the effect in places.

Hopefully, the outcome gives an impression of carefully nurtured decay.

There are still areas in which I feel I could have added more detailing, but for the time being, I am quite pleased with the effect.

Wiring-up the electrics

 Now came the most exciting part of the build - seeing if my efforts would actually be productive - whether or not I would have a functioning model.

Because I wanted the two halves of the model to be separable, I wired in the smallest plugs and sockets I could lay my hands on - servo plugs. These were soldered to the leads from to/from the Rx65b receiver/controller - ie the power leads and those going to the motor.

The two-way one pole switch and the 2.1mm power socket for charging were bolted into the mounting plate ....

 .... and then wired up. A 1.6 amp auto-reset circuit breaker from Maplin (the blue thing in the background) was wired into the power lead to the batteries.

 Two tagged 14500 AA sized li-ion batteries were purchased through eBay and these were then soldered into the circuit in parallel.

  The batteries were then secreted behind the buffer beams - a tight squeeze. Rather than the two AAA alkaline batteries in battery boxes which were recommended for use with the kit, I was anxious to have rechargeable li-ions. As each of these delivers 3.7v, I wired them in parallel so they would be able to provide 3.7v, but twice the running time (2 x 2.3Ah = 4.6Ah). As the motor will probably only draw around 0.5 amps when running, I anticipate I will be able to get around 9 hours continuous running from one charge - I will test this later.

 Fitting the wiring under the bonnet was a tight squeeze, but with some careful packing it was achievable.

The Deltang Rx65b receiver/ESC was mounted vertically inside the back of the cab, behind a false partition. Fortunately, although I couldn't see the LED on the receiver to check its status, I was able to bind the receiver to the transmitter and a trial running session proved to be very successful.

The Driver

However, as some of my fellow modellers pointed out - she looked a bit odd running without a driver and so I turned my attention to providing one. My initial efforts with modelling one in Fimo proved to be somewhat less than successful and my stock of possible candidates from commercially produced drivers seemed unpromising until I looked more closely at the driver which came with my other 32mm gauge diesel loco (see How I converted a small battery diesel to radio control).

He had already been replaced and when scrutinising him more closely, looked a possible candidate - though his limbs were all at the wrong angles. Some surgery with a craft-knife separated him into several component parts.

Wire pegs were inserted into strategic joints .....

.... and he was reassembled into a more appropriate pose for the driver of the Simplex.

His limbs were then fixed more permanently into place using epoxy putty.

Once this has set, he was given a repaint and a coat of (supposedly) matt varnish.

 He was then fixed into place with a blob of BluTak under is posterior.

Although his lower legs seem a bit long, he now seems very much at home in his new environment.


I appreciate that my modelling efforts are by no means perfect - as revealed by some of the close-up photos. However, I feel quite pleased with the outcome of this project. I now have a reasonably realistic looking loco of the right period trundling up and down the feeder line to the Copper Mine.

I am intending to make this loco dual gauge. I have sent off to IP Engineering for a 45mm gauge sub-chassis which can be exchanged for the 32mm gauge chassis by removing a couple of nuts (see photo above). This means 'Emma', as she has now been officially named, will be able to run the full length of the main line as the fancy takes me.

Update - 4/7/15
 I have now completed the 45mm gauge chassis and so Emma can now run on the main line as well as the mine feeder. Before I added the chain drive, her hauling capabilities were quite limited (3-4 LGB skips on the level), bit now she is 4wd, she is remarkably powerful for her size:

I am also considering using the auto-shuttle feature of the Rx65b (see How I re-programmed a Deltang Rx65b for auto-shuttle control) and adding some basic form of sound card - possibly by adapting a board which is used inside greetings cards. However, this is some way down my lengthy to-do list and may not be effected until much later in the year.

Update - 25/6/15
 She now has been given a very basic sound system based on a greetings card sound module (see How I modified a greetings card sound module to provide a basic sound system ).

 The advantage of this approach is the price (less than £1.50), whilst the disadvantage is the low fidelity of the sound and at present it has a half second pause every ten seconds. However, it is something I can live with until I find an alternative:

In them meantime, she has now become a much-loved addition to the loco stud on the railway.