WRRC Forum

I have been asked about chain dog fittings on the top of the tanks of TVR tank locomotives. According to the Naismith Wilson manufacturing drawings for the A class they were 2ft 0 1/16in length, 7 1/4in width, 9 1/2 in height overall. And certainly TL Jones included them on his drawings of the A at least.

My impressions are that they were removed before grouping and were potentially on either side of the loco, were they on both sides, and were all engines fitted? Certainly at least some of the M, U, U1, C, I and As had them at some time based on photos.

Another obvious question is what the chains wound round the dogs were intended to be used for; guesses are towing or rerailing wagons using the coupling hook; I guess you would not want to do anything to damage the water integrity of the tanks

Has anyone found an OO gauge equivalent or is anyone prepared to 3d print them?

Basil

I have built a U or U1 (can't remember) and I did it to photos. The chain dog was on the left hand tank and it was a right hand drive loco (from memory, Taff locos could be either left or right) Your dimensions look about right - I had to scale from a photo. I found that the T.L. Jones drawing for U's contained some errors, especially the cab so you need to be careful.

I do have some pictures of TVR engines in GWR livery still having the chain dogs fitted but they did not last long after grouping.
My understanding the chain were for shunting in confined sidings.
I have a copy of a works drawing for a O3 and your dimensions look right.
The ones fitted to the C class look different but I have no drawing to be sure.

Modellers (in 4mm scale at least) may be interested that 3d-printed models of TVR chain dogs are available from Shapeways (see here: http://www.shapeways.com/product/VTCACR ... d=60054209.

They were produced from the Naismith Wilson Class A manufacturing drawings which were highly dimensioned! (Length 2ft 0 1/16in long).

The Shapeways ones are in clear material - I received some on Friday and thought they had left them out of the box. Delicate because of the spikey nature but not fragile. Match the TLJ A Class drawing)

I is interesting that the Class A had them at manufacture as they were mainly for passenger workings.

(I am awaiting developments on the 4mm TVR mileposts - there is a problem with the size of the rod immediately below the disk)

Regards

Basil