Thursday, 22 October 2015

USATC S160: Cab, Part 1

So after deciding to do the lighting for the S160 next, we then changed our minds and started the cab instead!

Here we see the basic outlining of the cab and backhead.

Next we built the original style firebox door with shroud, fitted all of the control taps to the roof and added the basic window shapes.

After this the original lever reverser was built, along with the water taps (each side next to the seats), an alternate fireman's seat (a tool crate.. which we accidentally rendered with the seat still in place as well!) and the tap on a long rod that sticks out to the right hand of the cab - more on this in a moment.

The next task was to make the various gauge glasses - a vital piece of equipment for making sure the boiler has enough water. The S160 originally came with a single USA style gauge glass although some were later fitted with a second glass in case of failure.

After the war many S160's had generators fitted and this allowed them to have electric cab lights as well as locomotive lights. This is a soviet added lamp for the single gauge glass.

Some S160's were later fitted with UK style glasses, especially in preservation, and again these were fitted as singles or as a pair.

It has been stated that the original gauge glasses fitted to S160's were poorly made and were responsible for causing some boiler explosions, however this is not true.
The problem was actually caused by the odd placement of the top shut off valve for the gauge glass. We'd read about this during our research but it wasn't until we built the components that it made sense.

As you can see, the top shut off for the glass is operated by use of that tap we saw earlier on the right hand side of the cab, via a universal joint and a very long rod.
Looking at it from this angle it's very clear how the tap is connected, however we took the roof off to take this picture! In reality, with the joint being behind the large board holding all of the control taps it's really unclear to the footplate crew as to what this tap sticking out at an angle is for. And this is how the tragic boiler explosions occurred - crews who had little time for training (there being a war on) turned this tap without realising that they had closed off the gauge glasses top exit, thereby creating a vacuum and causing the glass to report incorrectly.

There is still plenty of modelling to do on the cab for all of the basic fittings, and then of course we have lots of options which include regulators, reversers and 3 different types of brake controls.

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