Building a DMU
Part Nine: The Drivers Compartment
Images eighty-three to ninety-two in the construction booklet are shown here, as with the rest of the images they are shown in the order presented in the book rather than numerically (negative numbers) or date. All show the interior of completed drivers cabs.
The first four were taken on the 15th May 1956 showing an intermediate brake third power car. There were three types of power cars built, the intermediate brake and non-brake cabs would be identical. The 'leading' cab did not have a drivers desk the full width of the compartment, I have never come across an image which shows the non-drivers side.
The other six (which are consecutively numbered) were taken on three different dates in June / July. Notice that the vehicles are now 'seconds' rather than 'thirds'.
"Intermediate Brake Third (Drivers Cab)"
Negative 5CR19
Hanging behind the drivers seat are multiple working cables. As there are only two it can be assumed that every cab would carry two to provide the four required to couple to another set. Under the small armrest are the heater controls, a toggle switch for off / on (it controlled a small electric fan connected to the heater ducting), and two sliding controls connected to Bowden cables, the top one controlled a flap diverting the output to the cab (near the drivers feet) or the windscreen (as a demister), the bottom was for hot / cold, another flap controlling whether the air was drawn from the heater ducting (which would require the Smiths heater(s) to be running to get heat) or from the small grille under the drivers droplight on the exterior.
"Intermediate Brake Third (Drivers Cab)"
Negative 5CR18
Starting at the top, the electrical panel has the fire bell and communication buzzer, three light switches controlling the head code, drivers cab and vestibule. The gauges are air pressure, a duplex for vacuum (brakes), speedometer, and the engine rev counter. To the right is the control switch, which had a detachable key acting as a master switch to turn the electrics on and off (this would become the FG1 switch on blue square and similar vehicles). On the desk is the vacuum brake control and the gearbox control, which also has a place for a removable handle for forward / reverse control.
"Intermediate Brake Third (Drivers Cab)"
Negative 5CR17
The air / axle and engine display panel also carries the engine start / stop buttons, the two start buttons would each start all the left side engines or all the right side engines. One stop button stopped every engine. There are toggle switches for the panel lights (illuminating the gauges), and to switch to the engine rev counter from one engine to the other, and a lamp for the deadmans control. Beneath is the throttle, to its right the small multi-layered round object is the windscreen wiper control, and then the horn lever.
"Intermediate Brake Third (Drivers Cab)"
Negative 5CR16
Under the desk the heater duct / outlet is visible. Immediately to the right of the drivers cushion, half hidden, is a small square box. This is an air pressure switch that will only illuminate the air/axle lamps when the correct air pressure has been reached. It has a small switch on it for manual testing. To its right is the Smiths speedo wheel diameter box. This would change to a circular box on the solebar on later DMU vehicles. Behind it, there appears to be no wall panel, and we see the asbestos spreayed onto the inner shell.
"Diesel Motor Brake Second - Drivers' Cab"
Negative 5CR37
Taken 28 June 1956, this is a leading (full width) cab. Without the partition immediately to the drivers right, the fire bell and buzzer are located above the windscreen. The speedo adjustment box has been moved.
"Intermediate Brake Second Drivers' Cab"
Negative 5CR38
Images 38 to 41 were taken in 4 July 1956. This intermediate cab view is very similar to 5CR18, but taken almost two months later. The differences are: under the buzzer a push button switch has been added - for the buzzer? It's not the best location since the driver would have to stand to reply to the guard; the light switches are missing their labels; and the air pressure gauge is black rather than white. The two removable items, the key switch and direction controller, are in place.
"Intermediate Brake Second Drivers' Cab"
Negative 5CR39
A similar view to the previous image, the camera turned more right, and the white sheet removed from the windscreen. Another difference from the earlier cab photos is the desk now has a piece of alloy trim at the edge.
"Leading Motor Brake Second - Drivers' Cab"
Negative 5CR40
A similar view to 5CR37 taken a week earlier. The difference seems to be this one now has a push button (presumably the buzzer) and two ight switches (presumably for the cab and headlamp) to the upper left of the windscreen.
"Leading Motor Brake Second - Drivers' Cab"
Negative 5CR41
As 5CR40 but reframed slightly lower, and with the 'white sheet' also covering the side droplight. The area under the desk still looks unpanelled, with exposed asbestos.
"Intermediate Brake Second Drivers' Cab"
Negative 5CR42
This image was taken on 9 July 1956, the third date that an intermediate brake cab was photographed. It would also be the last day that images were taken of the type until the buffet cars were ready in February 1957. The change in this view seems to be the bowden cable from the left of the heater controls now goes into an additional piece of wooden trim, the electrical connection to the switch is also better hidden.