Mock up of Ivatt 2-6-2 tank

I've seen a few pictures of a full size wooden mock up of an Ivatt class 2 2-6-2 tank, which was built at Derby in 1946. It's a very good, convincing fake, but why was it built, what was the point of it and what happened to it?

 

From memory it was done to get union approval for the footplate layout, maintenance accessibiity, that sort of thing - different times!

 

A Wooden Mock up of an L.M.S. Class 2 2-6-2T ordered by L.M.S. Locomotive Designer H.G. Ivatt photographed at Derby Locomotive Works ...this image dating from before 1946 when the first of the Class LMS No.1200 / later B.R. No.41200 was introduced.

Image source L.M.S. / British Railways /scrapbook scan via IP.
Presumably this one:

 

Fairbourne ordered a wooden mock up of his 2-6-4 and Cox judged it little money well spent.
Ivatt ordered it removed from planet when taking over.
Britania cab section was modelled in wood and shown to unions and workshops.
Fairbourne was WW1 pilot and had aircraft manufactoring expirience.

 

The Brit cab mock-up was ordered by Riddles who wasn't happy with the first attempt, ordering more detail and a better standard of finish. Enginemen's representatives were allowed to examine it and make recommendations. That didn't stop others from that fraternity complaining about it throughout the lifespan of the engines!

 

Before CAD it was a good way of working out whether everything fitted. They used to make one third scale wooden models of submarines for the RN to check there was room for pipe runs etc.

 

Swindon had their own system.

 

I can see that, but surely not necessary to build a whole model loco, why not just a cab? It was never done for any other types, and as the class 2 tender version already existed, the accessibility etc would be very similar

 

Perhaps there was a thought that by doing it more fully, the advantages of the cab mock up could be achieved for the whole locomotive? After all, maintenance isn’t just in the cab area.

Given what’s been discussed on other threads, notably the work by @S.A.C. Martin, it would be interesting to know what was going on within the industry, and what ideas were being played with.

 

They would of course.

 

Just been reading about the mock up. It only had wheels and motion on one side. The other side was jacked up. Incidentally, 46400 was finished at Crewe Works on 10.12.1946 and 31200 was finished four days later.

 

Building the remainder of the driver's side may have also been beneficial to judging the driver's field of view out of the front window for signal sighting, something that still occurs to this day on modern fleet design and commissioning.