The Great British Railfanning Trip - Acton Depot, Part I

Frank writes...

I just flew in from Gatwick, and boy are my arms tired! It's true, I spent the better part of a week over in sunny England along with Zach and Greg from the Car Department. We made a whirlwind tour of several railway hot spots in southeastern England, saw some tremendously impressive heritage operations and exhibits, met some great people, and enjoyed some excellent food. And most importantly, generated some more blog content to keep the Editor in Chief happy! So let's get right to it.

Our first stop after landing and checking in at the hotel, which was near the Hammersmith stop on the Underground, was the London Transport Museum Depot (that's "depp-oh" and not "deep-oh" to you) near Acton Town Station. It's not normally open to the public except for a few Open Days each year and tour groups, including school groups and drooling Americans.

Our host was Geoff Thorne, who heads up a group of volunteers who are restoring a Q38 class Driving Motor dating to 1938. Geoff had e-mailed us a year or two ago asking about GE style contactors (the reason will be obvious shortly) so I asked if we might be able to stop by and see their progress. Geoff and the other project workers were extremely generous with their time, showing us all of the work they've been doing and taking us on a tour of the entire depot. We can't thank them enough - it was absolutely fascinating! Above is an interior view of the Q38 car they're working on, number 4417, built by Gloucester in 1938. It looks like some of the projects at IRM! Above that is an exterior view from the LU website. I didn't get a very good photo of the car's exterior.

The volunteer group has a lot of work to do. Not only do they need to restore the Q38 car, which eventually will be part of a four-car train of Q stock including two Driving Motors and two trailers, but they also need to install modifications to allow it to operate on the modern Underground network. This includes adding a spot inside the car to store an adapter coupler. Underneath that plastic bin, in the seat frame (note the cushion outline on the wall), is a case to hold the adapter while the battery that was originally located under this seat has been moved to the seat across the aisle. These cars use Stearns & Ward couplers, same as our 4000s, so the adapter goes between that type and the modern LU coupler design. They are also overhauling door motors, a couple of which can be seen in the above photo. That sounds familiar.

At the end of the car are the control panels for the guard, which have been restored by the volunteer group using components salvaged from other cars.

As we descended to track level, I spotted this on the workbench. That looks pretty familiar! These cars used a variant of GE Type M control which was manufactured in Britain under license. Although built in 1938, these cars used electrical equipment from earlier sub-surface cars, so their motors and controls are mid-teens vintage. This controller looks pretty similar to a C6, with some changes of course.

This looks familiar too. The Q38 uses contactors similar to the DB260 type ones used under the 319. The volunteer crew pulled one contactor off the car and rebuilt it; here we're looking at the back of the contactor at the interlock assembly. These cars had automatic acceleration so there are a lot of interlocks, more than on our CA&E wood cars. This was a question they had for us: what are the specifications for the distance between contacts when the interlocks open? Unfortunately I have no idea; with generally low current flowing through these interlock contacts it always seemed to be an "either it works or it doesn't" kind of situation.

But the guys working at Acton are a bit more precise. They have built a very impressive test rig, part of which is shown here, that allows them to control all of the functions of the contactor box using a laptop. They can execute a program which runs the sequence up slowly, rather than at high speed as would normally be the case with an automatic acceleration system not under load. A lot of engineering work went into this test system and it's really something to see.

But it doesn't just control the contactors - it also measures the current load to see exactly how they're working and plots it out on a graph. Here you can see the result; note the transition from series to parallel in the center. Wow, neat! Part of the reason they developed this was to more closely analyze each step in the acceleration process to more effectively identify trouble spots, but another part was that there's no 600-volt (actually, 630-volt) line power in the depot. Everything has to get towed outside into the yard before full voltage can be applied to it, and at that point you're effectively on the main Underground system, so your train had better work right!

It was fascinating seeing the work being done on the Q38 car, but that wasn't the half of it. We were then taken on a tour of all of the other equipment stored in the very impressive Acton Depot facility. Of the four-car Q stock set, two cars are stored inside and two are outside tarped. The other car stored inside is this trailer, a Q35 class car built in 1935 by Gloucester as an N stock car. It has been fully restored.

Although in rough shape, this is a very historic car. And believe it or not, it's a Met car! It was built in 1904 for the Metropolitan Railway (of London, naturally) as one of the first MU cars for that newly-electrified line. It's a Driving Trailer, in British parlance, or what we would call a control trailer. It has not only been stripped of much of its equipment but also suffered a serious fire, so large parts of it are badly charred. But we know that even something fire-damaged like this is restorable and it's laudable that the car has been saved. Ex cineribus resurgam!

This is one of three existing examples of an R stock Driving Motor. It is car 22679 and was built by Metropolitan Cammell in 1952. After WWII the Underground started building cars out of aluminum (er, aluminium) and this was the first series which was left unpainted. It was retired in 1983.

Then before we proceeded to the rest of the equipment at the depot, there was a large display area at the front. For a facility not normally open to the public, they have some stunning exhibits! One was this, the disembodied end of a 1906 Gate Stock tube car. This car was built for the Great Northern Piccadilly & Brompton, today's Piccadilly Line, and was retired in 1929. At that time the end was cut off, presumably as an historical curiosity, to preserve the (already archaic) open platform.

Here's something neat - a very early electric motor from the Underground. As Zach reminded me, it's from a City & South London locomotive of about 1890. A complete locomotive of this type is preserved in London and we saw that one later on our trip. Anyway, this is a pretty primitive system befitting its age: the axle forms the motor armature shaft, like on our New York Central S-motor, and the commutator (visible just to the right of the near wheel) and brush holder aren't even covered.

Here's a section of a spiral wooden escalator. I bet this had to be seen to be believed, but it was a notable failure and lasted less than a week in service. Apparently this fragment was found in the bottom of the shaft where the replacement escalator was installed.

Near the displays sits the storage area, which is awfully impressive and something we could use at IRM. Someday!

A section of tube, like used in the tube sections of the Underground, was on display. These tunnels are only about 12' in diameter which explains why the London tube cars are so short in height.

There was this display of beautifully restored substation equipment...

...and this display of beautifully restored point lever machines (I'll need to look up what the proper term is). To the left is Steven, who led our tour around the depot.

There was a whole area devoted to old ticket machines and ticket booths, both essentially extinct now that Oyster cards are the payment method.

This was an awfully impressive exhibit. Pretty much an entire car's worth of control equipment off of a 1967 Victoria Line tube car has been set up, and wired up, as an exhibit. The cab in the center is basically complete; the electrical equipment you walk past, and under, to get to the cab is functional and is controlled by the driver, just like on a complete car.

The various portions of the system are even labeled. And since these cars were built with ATO, an automatic train operation system, there were three different generations of the ATO equipment box on display. Very impressive!

And there was a cab from a 1962 stock tube car available for photos. So of course I availed myself.

That's it for Part I... click here for Part II of our tour through Acton Depot!