Wrenn Class 08

[reddragon]

Is it possible or easy to fit a DCC chip on a Wrenn class 08.

 

I know the space is tight but I am also worried the Wrenn locos pull a lot of power too

[JST]

It is always possible. I can't help with the space question but I can tell you that when,  out of reasons to do with nostalgia, I converted my Wrenn "Dorchester" to DCC I got the armature rewound and the magnet re-magnetised. This brought the amperage pulled by the loco right down to an acceptable level for a DCC decoder. Even so, I used a Digitrax decoder that handles 1.8amps.

[giz]

I think you will need to insulate one of the brush housings as well, I took a quick look at mine a couple of weeks ago and it looked like only one side is isolated from the chassis. That would involve opening out the hole the brush sits in and adding an isolating bush.

Edited July 2, 2020 by giz

[JST]

3 hours ago, giz said:

I think you will need to insulate one of the brush housings as well, I took a quick look at mine a couple of weeks ago and it looked like only one side is isolated from the chassis. That would involve opening out the hole the brush sits in and adding an isolating bush.

 

Correct! I forgot that it had to be done to my loco.

[34theletterbetweenB&D]

23 hours ago, reddragon said:

... I am also worried the Wrenn locos pull a lot of power too

Assuming that it runs well and the motor gives evidence of a good magnet by being near unstallable, measure the current draw stalled at 12V DC from a controller contemporary with H-D/Wrenn that has plentiful current output, and use a decoder rated for at least double that measurement in continuous output.

 

I have used nothing but Zimo decoders to convert these old heavyweights with high current draw motors. You will likely wince at the price, but the range of motor supply CV adjustments available will cudgel these old brutes into running as sweetly as a modern RTR or a good kit built mechanism, with a can motor and multi stage gear train.

 

What it cannot do is eliminate the mechanism noise. There is a good alternative. The Bachmann 08 can readily be packed with lead to 400g for full on traction, and has the benefits of a large can motor with low current draw that runs superbly on a Lenz Standard, 40:1 ratio multistage plastic gear train for quiet operation and a sprung axle for enhanced pick up. (The Hornby 08's construction is not so well adapted to weight increase, lacks a sprung axle, but is otherwise mechanically equivalent and looks very fine.)