How to convert Tomix Percy to DCC

This guide covers the following models:

• Tomix N Scale (N Gauge) Percy 6 (93704)
• Tomix N Scale (N Gauge) Percy 6 (93808)
• Tomix N Scale (N Gauge) Percy 6 (93811)

This particular model of Percy hardly has any space at all for a decoder. This conversion requires milling out part of the chassis to make space, and even then only very small decoders such as ESU LokPilot 5 Micro decoders will fit.

Step 1 - Remove body

Unclip the body by pulling gently upwards. If it doesn't want to move, there is a clip at the front underneath Percy's face, and two more at the back.

Unclip the running frame and take it up over the chassis also, being careful not to snap it. You may have to bend it out slightly to get it over the clips. Remove the valve gear piece from the front.

Step 2 - Disassemble Chassis

Remove the screw underneath, and then use a small flat headed screwdriver at each end to release the keeper plate. Take out the couplings and coupling springs, and put them aside.

Take the wheels out, which will allow you to unhook the rods from the metal guide.

Remove the two screws from the side of the chassis, then split the two halves. Remove the two contact springs touching the chassis and the motor.

Remove the motor, flywheel and worm gear, then all of the smaller gears. Remove the two plastic spacers that maintain an insulated gap between the two metal halves.

Step 3 - Mill Chassis

Use a Dremmel or similar tool to mill out part of the chassis from above the motor as shown.

Step 4 - Connect Motor

Solder a grey and orange wire to the motor contacts. Refit the motor.

Step 5 - Reassemble Chassis

Refit the worm gear and smaller gears, then put the two chassis halves back together. Remember to replace the two plastic chassis spacers.

Replace the two nuts and screws, but do not overtighten.

Refit the wheels, remembering to thread the rod back over the centre valve gear guide. Refit the valve gear plastic piece to hold everything in place, followed by the running board / outer frame.

Step 6 - Connect Track Pickups

Scrape away some of the black paint and fix small pieces of conductive copper tape as shown. Solder a red and black wire to each side.

An alternative method is to leave the motor contact springs in situ and solder the red/black wires to them instead. The orange/grey wires and the motor terminals will need to be covered in shrink sleeving to prevent them making electrical contact with the springs.

Step 7 - Fit Decoder

Solder the red, black, orange and grey wires to the decoder. Enclose the decoder in kapton tape to prevent it touching the chassis, and sit it in the recess milled out earlier.

Step 5 - Refit body

Clip the body back on and test, and the conversion is complete.