July to August ’09
One becomes two…toy trains are addictive!
Once plans had been obtained and a scale found that would accomodate the major traction components, the drawings stage could begin. The drawings from the Ffestiniog Railway and Garden Rail were blown up to actual model size at Prontoprint and labelling of dimensions and any stretching or tweaking could then be done. Using these, the drawings of individual components, both internal and external, could then be produced.
The drawings had to be very detailed, then checked over and checked again – these were the masters going to Dales for input into their computer controlled laser cutter. A significant amount of time and effort went into producing these drawings, but in fact doing this saved a lot of time and effort in the workshop. Its not just one of each component you need when building a locomotive, let alone two; for example, the little strips of metal that pack out the bearings in the frames; there are four per bearing, six bearings per loco and two locos to complete so a total of 48 parts. While its not difficult to make these, it is time consuming to make by hand, but its a whizz for the laser cutter to cut out and spot the drilling points for us with total accuracy. It’d be foolish to do otherwise, surely?
We did, however, make up by hand all the L shaped bracket parts for supporting the battery cradle and the running boards, which is a good place to start the photo documentary as thats the first picture I took!
These were cut from large steel box section which was going for scrap (!) using a bandsaw borrowed from KLDSME, and then milled square and even. These were to support the batteries, which, to retain the proportions of the loco, had to be sat down in between the frames.
The locos are to run on Engineers Emporium CNC turned wheels, we’re using the design to the left which are the 5″ diameter Narrow Gauge tread and flange profile, to the right are the standard gauge tread and flange profile version which Mike has used on the Class 04 Drewry locomotives.
The bits box grew over the weeks, we occupied our time making parts and components while waiting for Dales to be able to slot our parts into their busy schedule. Here you see the axles, a Maxitrax coupling block, beside that a scratchbuilt coupler for the front of the loco, lifting brackets and all manner of bolts and sockethead capscrews.
A hard day’s work, and he’s still smiling! Mike scrubs up before heading indoors for the evening.
August to September ’09
The bearing units for these locos will be Mike’s favourite T204 take up units. These units are a common choice for miniature railway stock, however Mike chooses to modify them and this was another job that could be done before the laser cutters had made our components. The bearings are removed from the blue casting before work commences, swarf and bearings don’t mix!
The fixing point is cut off and milled flat, this means the loco’s frames don’t have to be made as deep as they would if you were using un-cut bearings, a significant weight reduction.
Secondly, a small oiling hole is drilled through the casting to the bearing surround – a grease nipple fitting is supplied but in this application that is likely to be inaccessible as it will be underneath and liable to get squashed if the loco should be derailed. Lubricating this part is essential if the bearing is to continue its side to side and swivelling motion – which is fantastic for miniature railway stock as it helps the ride over the inevitable odd bit of lumpy and twisted track.
Thirdly, a large drill or countersink is used to enlarge the oiling hole out (photo above) to create a funnel shape for the oil to follow (photo below, bearing closest the camera) , then lastly the castings go and see the milling machine and the funnel is squared off a few millimetres to give the suspension spring a proper locating hole: photo below, bearing furthest away.
There is provision on all of these bearing units for a grease nipple, but given the position of these there’s a fair chance they will get squashed and broken should the train be derailed. You also have to be able to get underneath the loco to access them; not always possible if you’re going round with the oil can halfway through a day’s running. With this modification, all you have to do is drop some oil down the centre of the spring and it will find its way to the right spot.
And this is how they look in the frames, fitted here to the 4th set of Drewry frames – the Baguley sets hadn’t been cut at this point in time. Neither the retaining capscrews nor the 3mm thick slips that go on each side of the chassis frames have been fitted in this photo, its just for illustration.
Another job well done – the gears were reamed out to fit the axles. Details on the gearing arrangement later…
5th August and the magic happened! Dales were able to fit us into their schedule and the bulk of the body and chassis parts were cut.
The laser at work..
Of course, no sooner had the frames got back to the Workshop, the kettle hadn’t even boiled before a set of frames were slotted together. The tab and slots that Mike had designed into this loco meant that this was possible in less time it took for Pam to make a brew!
The side panels of the loco… looking good!