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BR Swindon Type 1 - Class 14 Locomotives
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Heljan Class 14 EM Gauge Conversion - by Paul James
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Dave Alexander kit-built Class 14 ‘D9502’ has had the rebuilt mechanism painted and refitted
and is now ready for a return to service. Gibson wheels and a High Level gearbox have been
used in the rebuild.
Class 14 - Morfa Mawr D9508 (circa 1968). Heljan/Hattons model, a reasonable amount of work
was carried out on this loco, but well worth the work I feel. The cut out on the buffer beam
where the coupling came through was filled with plasticard and filler, but whilst I did this
the buffer beam protrudes to far forward. So I have cut them off first and moved them and the
front of the footplate back to a more prototypical position, this does mean you loose those
ghastly working lights, but this was not a problem to me personally, I also filled the gap
between the buffer beam and steps with a piece of plasticard, which seemed to be missing at
one end. Other work carried out included moving up the rainstrip on the cab roof, smoothing
the rivet detail around the cab windows to be less prominent and filling the indent on the
engine room door, a modification not carried to all the class. Numbers were supplied
by Cambridge Custom Transfers and the EM wheelset Is the Ultrascale conversion.
D9524 waits for the road ahead to the south of Shenston Road station (Heljan model).
From the Shenston Road fleet come D9535 & D9524 working in tandem (both Heljan), heading a
trip freight from Acton Yard to Temple Mills.
Another view of D9535 (Heljan).
Underside view of a Heljan class 14 chassis as bought - OO gauge. For some time now I had been
looking for ways to convert my loco fleet to EM gauge using the original wheelsets. You can
buy scale wheelsets and wheels to convert most locos, but the cost and availability of them in
some cases led me to consider other options. This and the improving standards of the wheels
being provided by the RTR manufacturers led me to look at turning down the wheelsets that came with the loco.
Access points for keeper plate. One thing I would recommend before starting this project is to
remove the cab from the body following the Heljan instructions provided. This will prevent any
damage to the fragile fittings on the cab roof.
One end of the keeper plate lifted. The first thing is to remove the wheelsets from the chassis.
This is the tricky part as there is no obvious way to remove the keeper plate from the bottom of
the chassis. I did it by carefully leavering the keeper plate upwards by sliding a thin object,
in my case a knife blade (but be careful as I managed to break one off in the proccess) into the
slot at the end of the chassis.
This should release the clips holding the plate in place, they are located either
side of the axles and are indicated by the red arrows. By carefully sliding a blade or thin
screwdriver along the chassis the remaining retaining clips should be released. Take care around
the drive axle as the gearwheel makes this part of the retaining plate the weakest and most likely
part to break. With the keeper plate removed, the wheelsets can be lifted out of the chassis.
I decided to tackle one pair of wheels at a time. This ensured I didn't mix up them up and that
they went back together in the correct positions, especially in relation to the coupling rods.
Detach the wheelsets from the coupling rods by carefully pulling out the crankpin
retaining pins and putting to one side. Take care when doing this as it is very easy to bend the
ends of the coupling rods.
I decided to mount the wheelset in the lathe as a complete pair on the axle. This
would allow me to see how true the wheelset ran, and also that I would not have to re-quarter the
wheels as I would not have to put them back onto the axles. Experience has shown me that as long as
you are careful in positioning the wheel in the chuck and positioning the cutting tool perfectly
acceptable results can be achieved using this method. The RH wheel has yet to be turned. One further
action was to wrap a length of masking tape around the gear on the driven axle. This prevents swarf
from getting into the gears when turning.
Now to set the wheels to EM gauge I found the easiest way was to mount the wheelset
in a vice, loosely but ensuring the wheel is well supported, then with an old axle and a pin hammer,
carefully tap the axle through the wheelset very gently and a little bit at a time equally on both
wheels until the gauge is set. If you take your time and don't rush it then you should be able to get
even movement of each wheel on the axle. This is especially important on the geared axle where the
drive gear should remain central.
One thing about using the original axle is that it's slightly too short, so after
regauging this can be remedied with a bit of filler.
With the wheelsets now finished it can now go back into position with the coupling rods. As well
as the wheels, the jackshaft also needed to be opened out, not very far, just enough to make its
overall width the same as the wheelsets. Go too far and you run the risk of fouling the
cab footsteps or the balance weights.
You will also have to add washers on the axles behind the wheel to cut down on sideplay. I used
Peco 2mm fibre washers and as I had not removed either wheel from the axle, fitted them by cutting
through on one side and twisted out of shape to enable them to be fitted over the axles. Once
on the axle they could be returned to their original flat shape.
You will have to decide for yourself on the number you put on each side, but after trials on
Shenston Road I found 10 either side worked best. The trials also showed the need to add washers
to the jackshaft axle as well, and avoid clearance problems with the cab footsteps.
The loco comes with the brakegear as a separate fittings so they need to be fitted back with care
so as not to foul the wheels. I did this by making packing pieces from 2mm x 1mm thick plastic
strip with holes drilled in to fit the brakeshoe fittings and then glueing into position on the chassis.
When the modified brakegear is glued back onto the loco, I found super glue the best, the actuating
rodding also supplied with the loco will now not be wide enough to fit between the brake shoes.
I looked at many options to correct this but in the end decided to cut out the center crosspieces
off the brake rodding and glue the pull rods onto the back of the brakeshoes. One advantage of this
was it allows the Keeper plate to be removed in the future oiling and the like. One thing I did before
fitting everything back together was to cut a couple of small notches in the ends of the Keep plate to
make it easier to get a small screwdriver in to lever it up in the future.
Attention will now turn to the body, especially filling in the big holes in the bufferbeam. I'm not
convinced about the area above the cabside windows and the rainstrip, so may have a look at that in
the future. I've now got another Class 14 to modify, and have already applied the technique to a
Bachmann Class 9F with pleasing results.
Conversion finished and almost ready to earn its keep. Other recent conversions - In the case of
the LMS Prototype Twins, the original wheels are quite capable of just being spread on their axles
without the need to reprofile, and have run well on Shenston Road and Wibdenshaw. As I possessed
an old but servicable Unimat lathe and was reasonably competent with it, the first loco to be
tackled was a Heljan Co-Bo. This loco came with chunky flanges and was a useful learning curve
on various techniques, and how the slightly finer flanges perform well through EM gauge pointwork.
