Missing or broken drawbar contacts on Chinese-made tender-drive locos

[Topcat2018]

Call myself an engineer! I've always been annoyed by the flimsy contacts on top of the drawbars of Chinese-made tender-drive locos. Apart from a few locos that I bought boxed and were in very good condition, almost every one of these locos I possess had damaged or missing contacts. Whoever thought they were a good idea I don't know.

In the interests of restoring the locos to original condition I've attempted various repairs with mixed success, often ending up with the plastic part of the drawbar melting, but suddenly it occurred to me that these top contacts are completely superfluous if you are using analogue control, as I am, and are probably only needed if using DCC.

In the case of both British and Chinese locos the left-hand wheels are connected to the bottom contacts of the drawbar, in the former case via the loco chassis and pony truck chassis, in the latter case by pickup contacts and wires.

These contacts are connected via the pin on the tender to one side of the motor.

In the case of the British locos two of the right-hand tender wheels are connected to chassis, as is the other side of the motor, thus making the contact with the right-hand rail.

In the case of the Chinese locos the right-hand wheels are connected to the contacts on top of the drawbar via pickups and wires then via the the flat plate on the tender to the other side of the motor. The right-hand tender wheels are also connected to the motor and to chassis by spring contacts.

If you are using DCC then these connection between the motor and chassis need to be removed since you need both sides of the motor connected to the decoder, but for analogue they provide the connections to the right-hand rail that are needed.

I don't know why I did't realise this before, probably because it's only recently that I've had to dismantle a Chinese tender with a bad motor. In future any drawbars with good top contacts will be left as is but otherwise they will be cut off.

For DCC users I'm afraid I can't offer a quick and easy solution to broken drawbar contacts, and drawbars are expensive to replace, even if you can find the right one for your loco.

The only long-term solution I can think of is use PCB-CAD to design the complete top contact assembly, print it on phosphor bronze then etch it. Remove the old contact assembly by cutting away the plastic pin and de-soldering the wire. Re-solder the wire to the new assembly then fix it in place with epoxy adhesive.

[ColinB]

On virtually all my locos I replace them with the later arrangement of 4 pin wire and connector. I run DCC so normally there is not enough room in the loco for the DCC decoder and with all the wires it makes putting the loco body back difficult. So I have loads of these drawbar connectors as when I take one off to replace it I keep them. I must admit they all look the same length to me. I have also had issues where there is actually a short internally on some of them. The only ones I don't replace are the original Bullied Battle of Britain or West Country as Hornby changed the mounting points for the tender on the later ones so you can't use the later tender chassis, plus it is the only loco where there is loads of room to easily fit sound in the loco with a decent speaker.