Premise: class 08 never built...

... for some reason, Standard 0-6-o tank required for shunting. Your chance to design it.

My thoughts, it has to be outside cylinder, could a standard 2MT boiler be too big?

 

Can we just not build a batch of 15xx panniers instead?

 

Something based on GWR 15xx?
Edit, Matt37401 just beat me to it!

 

A batch of 'Austerity' tanks?

 

Buy more USA tanks?

 

the Austerities being inside cylinder would not seem to fit the Standard philosophy. I can't see a pannier being favoured by Mr Riddles and his people.

 

I'd go for a 15xx, but be a bit radical with the design, and have regulator, brake and reverser operable from both sides of the footplate so increase flexibility. Latter might require a steam reverser though. Give it all the modcons (rocking grate, hopper ashpan etc) and fit BR standard safety valves on the footplate rather than GW pattern. Fit electric lights on either end, and have similar lighting arrangements to those on the Bulleids for viewing things like injector overflow pipe etc.
If you needed some with a shorter wheelbase, build/buy more USA tanks, if you build them then fit similar modcons to those on the 15xxs

 

Might it get a tad loud and steamy for the crew? it would cure the more enthusiastic firemen though

 

I highly doubt a Jinty would be considered, for the following reasons
1: Inside valve gear. BR would almost definitely have insisted on a loco with outside valve gear
2: I would not be surprised if they also insisted on a taper boiler to fit the rest of their locod
3: Greater wheelbase than other options already suggested, like the Austerity, USA and 15xx
4: The Jinty was dismissed as an option for a standard shunting loco during WWII in favour of developing the Austerity. So it's incredibly unlikely that they would revisit the loco that was deemed inferior when on the lookout for a standard shunter for the second time...

 

Build more of Maunsell's three cylinder 0-8-0 Zs - quietly very effective & reliable with the even torque enhancing
the total adhesion.

However the speed over the hump in that sort of marshalling yard needs to be very exact and steady: to get this
diesels or electrics might have been insisted on for BRs concentration yards like Kingmoor. Also shunting was what
diesel locomotives first showed clear advantage on and I think they had already got one man operation.

Leaving the Dukedogs out of it, I cannot think of any new British class with a rigid outside frame with outside cranks
and couping rods for a mainline railway in about forty five years before they emerged. In this the 08 & 09 survivors
are about a century out of their time - and I relish the anachronism steam though they aren't.

 

Good, workmanlike and strong, but a bit dangly at the extemities.

 

If you had orthodox steam arrangement frame inboard of the wheels this would need the traction motors to be much shorter and thus less powerful. Same reason as to why Diesel electric and pure electric locos have outside frames. Don't forget that the some of the early LMS 350 hp shunters did have inside frames, but the single traction motor was mounted higher in the frames with an external rod drive.

 

How long do sentinels take to bring into steam?

 

A.J. Powell, in "Living with LMS Locomotives", describes a proposal to rebuild the 3F Tanks with, if I recall correctly, piston valves and a geared drive. Had that come to fruition, the resultant gearing could presumably have been varied to create locomotives with a turn of speed, and also low-geared locomotives for yard shunting.
It would have been interesting to see how controllable a geared drive was, and also to see how large a train could be lifted, smoothly, without slipping.

Richard.

 

"Dangly bits" - is that a technical term?

The Z class was a very clever bit of design - worth reading Holcroft.

Without thinking too much about weight and size, I cannot help thinking that a 2MT boiler wouldn't be ideal - it's too optimised for continuous steam production, whereas for a shunting engine used for intermittent bursts at high output followed by pauses, a large water volume but small grate area is better - the large volume of water gives a reasonable reserve, but the small grate keeps total steam production low to avoid standby losses. The 2MT boiler also has superheater which is a hinderance: it adds cost both to construction and maintenance, while adding lag in regulator response (not good in a shunting engine) and providing no efficiency benefit for a loco used in short bursts.

Tom

 

USA tank English spec?

 

i hate to say this but the only engine i can think of is the ex GW 1500 it was i believe the GW answer to the Austerity tank, but outside cylinder, walcherts valve gear, didnt they also have rocking grates?

 

Pete Briddon (Weekend Rails blogger) has described the 08 as “a State of the Art (as at 1870 though) chassis, a State of the Art (as at 1930) traction package and a trawler engine.” He’s not a fan.

So what is the equivalent steam loco?

 

Generally a couple of hours, but they can empty a boiler even quicker, and aren't to keen on standing around for to long. All in all they need a good crew who are on top of the job and are probably a bit 'specialized' for BR type shunting.