Diesel Railcars for Chesham?

What an interesting read that turned out to be! Especially the bit about how do trip cocks work on a steam engine and the doubts of the signal engineers as to the efficacy of the trip cocks on steam locos.

As I've mentioned before on the District Line/Historic sections about stem on the Underground, most freight trains were unbraked apart fro the loco brake and the brake van at the end of the train. These trains required special careful handling and a long way to stop. I've personally driven unfitted and partially fitted trains on the main line not on steam I hasten to add, but diesels, which act in a similar way when it comes to braking. On a partially fitted train, a number of wagons at the front of the train would have operating vacuum brakes, the rest would be unbraked, giving the driver a better chance to stop a bit quicker! Pulling away took a lot of care, not to accelerate too quickly as the sudden jolt at the back of the train would injure the guard as it went from 0 mph to 15 mph in a spilt second. There was also the danger of breaking the couplings. When stopping, the driver would apply the loco brake gently to buffer up the wagons again to avoid a jolt at the back end. Stopping varied, unlike EMU stock where train lengths and braking was fairly standard. A goods train could be anything from 20 tons to 800 tons with just a loco brake. Any sudden application of the vacuum brake on the loco being tripped would make a big jolt.

Hence loco crews tended to pretend the vacuum brake side was cut-in and the trip cock down when in fact it was isolated! I worked on the Widened Lines in the last year of operation so am going by the tales of the Hornsey men who used to work freight down there. Co-acting signals were provides at locations to allow steam drivers a better view, the steam loco controls could be either side of the loco.

I've been actively helping in restoring the GW railcar at Tenterden hence the interest in this thread. Unfortunately I've not been involved for a few years due to bus restoration getting in the way!