Spot on Chris! How you knew that particular article is a wonder. Fundimentally my loco is close to the drawing. Recent history is that it was a running until dismantled for overhaul in the early 1980's and a new commercially made boiler was produced in 1984. It has remained dismantled ever since under a bench.
I have been assembling the parts, both to check what is missing and plan how to revive it. I am working on the basis that if it 'ain't broke do touch it'. Besides the Roblin cylinder casting it has the same valve gear slide casting as in Fig. 7. Not sure that this is model built by Roblin himself, as I assume in those days articles in ME were a way of publicising availability of products to other builders. As I mentioned before it has double frames rather like a GWR Armstrong goods, but the cab and side tanks are more LNWR as per drawing.
I have lent my camera to my daughter this weekend but will post photos early next week so Ian SC can comment. I guess the real next question is are there any other models to this design out there.
thanks again for the prompt feedback, Ieuan