CD motor in place of Hornby Ringfield

There were three motors in the CD drive which I dismantled. Two of them were marked "MDN3BT3CSAS". A data sheet of this family of motors by Panasonic is at

The another motor, more like the normal flat can type, I have still to investigate.

Here are a couple of pictures of the motor installed in place of the ringfield motor in a Hornby 125 motor bogie.

It was quite easy to put it in. The hardest bit was fitting the original Hornby gear onto the output shaft of the new motor. The new shaft is 2mm diameter and the Hornby one is a bit bigger. I filled the hole in the gear with solder, drilled it out to just under 2mm, put in a small taper with a round file, and forced it onto the shaft in the vice. Seems OK !

The hole in the back of the old motor casing needed drilling out to allow the gear on the motor shaft to go through.

As luck would have it, two of the tapped holes in the back of the new motor lined up with slots in the old casing, so the motor could be fixed using the screws which had held it in the CD rom drive. The head of one of these can be seen in the second picture.

The motor runs more smoothly than the ringfield and can drive a four car train easily. With five cars it gets wheelspin. This could probably be sorted by adding more weight.

The motor runs without getting hot, and stalled with twelve volts across it only draws about 400mA.

Return to John Dent's Homepage