Tumble Down Falls Railway: Bachmann Tram Battery Conversion

In June 2021 I attended the National Garden Railway Show in Peterborough, and as an impulse buy, I bought a Bachmann Tram, no box and wheels in a very poor condition:

	The first thing I did was remove the motor block, to inspect the wheels and drive gear, and decided that the whole motor block needed replacing:
Generally the replacement motor block was okay, however the screw post had split and did not hold the screw well. Plastic tube was glues over the posts to hold them in position and any gaps filled with plastic filler, with new pilot holes drilled down the centre. The strip down of the body then continued, and all the parts were given a good cleaning.

	The power on/charging module was fitted next, this needed to be discrete but with easy access, the motorman platform was eventually decided as the best place as is will be out of sight but accessible.
A specially set of Lithium-Ion batteries were obtained, 4S (14.4 volts) with on-board protection board. As can be seen, these sit under the floor between the motor and lowered driver's platform. It is held in place with Velcro.
	The Rx which is a Revolution Micro Receiver with Sound, Rx/ESC/Sound all in on. This was tested with the motor block on a rolling road to confirm all was working correctly
The Rx was fitted in the centre of the passenger compartment, it has four holes one in each corner for mounting. The red button (to the left) is the "linking" button, also known as binding. As this Rx has built in sound, a small speaker was fitted under the seats, denoted by the holes to the right side of the seat
	The removed parts were refitted, with the front and read lights replaced by LEDs and wired directly to the Rx lighting positions. The body was lightly fitted on to the motor block.
All the wiring was cut to length and routed safely to ensure it would not chaff on any moving parts, especially the wheels. The final stage before fitting the roof was fitting the side frames, not shown here.

	It was identified that with the batteries at one end, it may cause an imbalance on the drive wheels, so a weight was to be produced. The first task was a container to fit the space, this is made from styrene sheet.
With the container was made, the outside, especially around the joints was covered in masking tape. I have found that the resin used to hold the weight in place will find any gap and seep out until set.
	The containers is filled with weight, in this case ballast weight used by divers, until it was calculated the total weight would be equivalent to the weight of batteries,
When the resin was dry this was held in place by Velcro.