BR(W) 16xx pannier tank

I know these are more or less to replace turn of the century very similar locos worn out at this stage but I wonder why ,if a lighter than 57xx pannier was needed, they didn't build more 74xx....are these even smaller /too small?

Was it the case that the "new"locos included parts of the older ones perhaps?

 

Was it the case that the "new"locos included parts of the older ones perhaps?[/QUOTE]

The 16xx were totally new engines and didn't incorporate a significant number of parts from the locos they replaced. IIRC the 16xx were smaller and lighter than the 74xx. Ray.

 

Yep, the 74s, although they were of the "small" Pannier tank line, were actually reasonably powerful - more powerful than the earlier pre grouping large Pannier tanks in fact, and also had 4'7.5 wheels like the 57s. The 16s had 4'1 wheels, were shorter with a rather smaller and lighter boiler, and were built to a very restricted loading gauge. I believe there were a lot of motion parts and so on in common between the 16s, the 54s, 64s and 74s and the 1400 0-4-2Ts.

Shame more 16s didn't survive: should have thought they'd be good for many preserved lines.

 

GWR panniers are quite complicated, but I thought that broadly there were two groups...4'7" wheels and 4'1"....the 27xx series would have been the predescors of the 57xx I guess , am i right in thinking that some of the 4'1" variety would have been similar to the 16xx ?

 

My take on it from a year or so ago is here:-
A Beginner's Guide to Pannier Tanks
I've learned more since then but yes, I think its fair to say there was a fundamental division between large and small types but what I call small types had 4'7.5 and 5'2 wheels in the 20thC.
The large classes went (inter alia) 1813->1854->2721->5700->8750->9400 and the small classes 850-2021-2101-[5400,6400,7400]->1600.
The Collett classes were roughly speaking at the sort of spec the pregrouping ones had been upgraded to at that time, but with all the latest advances in precision manufacture and the like.

 

that'll keep me busy for a while! Thanks!