Nodding donkeys- finally to be retired??

[kvp]

Just a reference on how to make reliable low cost branchline dmu-s, here is a link to some ancient pre war (1926) Ganz dmu-s (bcmot series, a few are still in use and they were remotored several times with various bus or truck motors):

http://www.benbe.hu/gallery/bcmot/low/43.jpg

http://www.benbe.hu/gallery/bcmot/low/24.jpg

http://www.benbe.hu/gallery/bcmot/low/37.jpg

(2 axle cars with a 6 meter axle distance and 12 meter length, single axle propulsion with a limit of one trailer per motor unit, the top boxes are the coolers for the engines that are sunk partially into the floor, the transmission is mechanical, the mu control is direct penumatic, total passenger capacity for a M-T-T-M set is around 180, a bit less on the still active heritage units retrofitted for wheelchair access a few years ago)

[Welshbloke]

The basic problem is building a four wheel chassis with one driven axle and four pickups, but with the pickups on the unpowered axle striking the balance between reliable contact and excessive drag.

 

You could do it with ball bearings (as LGB offer in G scale) or axle end pickups like Tomix and Kato use in N.

 

Also doesn't help that the chassis is fairly rigid - it really needs three point compensation, where you arrange for one axle to be able to swing slightly so all four wheels are always in contact with the rails.

 

A company called Realtrack Models are offering a much better attempt at a Class 143 and 144, they might do the others in future.

 

The Hornby tooling is strictly speaking only accurate for the original form of the 142s, I know the doors have been changed since and probably other things too.