Build An 04



How I Build An 04 Diesel

The 03 and the 04 use the same chassis the only difference being that with the 03 the resin bonnet takes up all the space in the bonnet and I have therefore mounted the motor vertically in the cab, driving onto the rear axle. Once painted black it is really not are a few pictures of the 03

Here you see the basic chassis with flycranks, gear wheel in place and coupling rods held on by pieces of flex covering. Note that I forgot to blacken the chassis before fitting the wheels

The same chassis with motor now in place


However, on to the 04. This is a very nice little kit produced by Worsley Works that builds up well and in many respects is a good starter loco. The only problem being that it has a fly crank which complicates the matter somewhat but these problems are really all in the mind rather than in practice. So, let’s get started.

Let us build a basic 04.

What do you need? You will need the loco body and chassis fret from Worsley Works which comes in a number of versions, outside skirts etc. You will need a motor and for this I would recommend a Machima 9 x16 (Finney & Smith) , wheels from Bruce Smetham (in practice these are from Alan Gibson). You will need 8 x 2mm top hat bushes and a Finny & Smith 40 :1 gearbox for 2mm axles.

O.K. lets start on the chassis.

Cut out the chassis fret, remove the brake gear from the centre and set brake gear aside. Open up the axle holes to take the top hat bushes, use a broach and they should be a tight fit. When these are in place solder them to the chassis so that the brim faces outwards for the wheels and is on the inside for the fly crank. The drive will be on the centre driver so cut off the projecting bush on the inside flush with the frame. Note that the chassis folds up into the bend lines which are always on the inside. Bend up the chassis ensuring that all folds are at 90º. At this stage if you are organised you could drop the chassis into a blackening solution for a minute of two, some of it will wear off while you are working on it but it does make painting easier at the end.

Take the wheels and using say a 1.4mm drill lightly countersink the back of the wheels around the crankpin hole, screw the 14 BA countersunk screw into the hole as a crankpin and secure with a little drop of Locktight or Superglue, do not open out the hole just screw it in and it will cut its own thread.

Take two of the coupling rods, open out the holes with a broach to a close clearance fit on the crank pin, take three wheels and insert the axles. Now for the magic bit, well not really it is simple, this is the quartering procedure. Let us clarify this, the term is a misnomer, they do not need to be exactly quartered or set at 90º to each other as almost any angle is acceptable except being in line or at 180º to each other. So whether it is 90º or 80º or 70º is irrelevant, judge it by eye and this is good enough. So insert one wheel with axle attached and put on the other wheel at about 90º put in the next wheel and axle and fit a coupling rod (remember the coupling rod is shorter at the fly crank end). Then with the coupling rod parallel to the chassis (top or bottom) put on the other wheel so that it matches the first wheel and put on the other coupling rod, if they do not quite fit tweak the wheel until it does fit onto the coupling rod. Do this by inserting a small screwdriver between the spokes and jam this onto the frame and stick a pair of tweezers between the spokes of the other wheel and twist until the coupling rod fits. Only one wheel is wrong so only adjust that one wheel. Adjust until the wheels rotate smoothly and you have an 0-4-0, repeat for the other wheel and you have an 0-6-0 easy peasy.

Now, for the flycrank. Solder the balance weight onto the flycrank, and open up the crank pin hole and solder a steel 14BA screw in, open out the axle hole with a broach and solder onto the final axle. Then fit the flycrank and axle into the appropriate remaining bush (now you see why the bushes are inserted the other way round). Repeat the process with the other flycrank and using the coupling rod as before solder it onto the axle. Use a hot iron with a blob of solder and get in and out quick. So now we have an 0-6-0 plus flycrank and everything should now go round smoothly. Part the other coupling rod from the fret, solder the pairs together and open out the holes to say 1.5mm refit the coupling rods and I am sure that everything will go round smoothly, put a 14BA washer between the coupling rod and the wheels and secure in place with the threaded washer supplied or when you loose them the 14BA nut, give the nut a tiny, tiny drop of Locktight or Supaglue to hold in place and cut off the remaining projecting crank pin.

So far I have not mentioned the gear box, make this up according to the instructions and fit on the centre axle so that the motor faces forward under the bonnet. Secure the gear wheel with Locktight (Dave Finny provides the appropriate cleaner and Locktight, expensive but worth it). Before you fit the motor open out the holes for the fixing screws by filing inwards as the holes as etched are actually too far apart. Fit the motor and add power.

I fit pickups using backscratchers, yes I know other people have better ideas but it works for me. I glue a piece of PCB between the frames and cut the copper down the centre and using springy wire I solder the wire onto the pcb so as to rub on the back of the wheels. Connect the pickups with the motor and away you go.

Chassis basically together including gearbox


Underside of chassis awaiting pickups



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Last updated:1-10-2006