New Build P2

Clearly any lessons learned from the first boiler would be incorporated in the any further builds. I was referring to the overall dimensions etc and hence interchangeability.

 

I don't think the boiler has given any problems since its minor rebuild has it - so it sounds like the dimensions and specification were perfectly OK, just the bugs needed ironing out in the modified stays and welding to give extra stress length.

Thompson - now if he had gone straight to B1s and K1s he might have been OK - but Great Northern's destruction - that sealed his reputation.

 

You can say that again, about Great Northern........having had personal experience of riding on the footplate as a spotty youth........how the crews managed is beyond comprehension............

 

Oh, no problems........one thing that always struck me about Great Northern and the converted P2's was that the cylinders were quite far back from the front end, they were'nt over the front bogie......it was always in my mind that this may have caused the "snaking"..................just a thought though......back to the subject....P2....if one ever gets built it will make my day. I think they were one one of the most elegant locomotives made.

 

Its been a while since I have posted up on here but I'm hoping I can bring something to the discussion;

1) Im not entirely sure i see the need/ use for a new P2. Currently preservation is unable to find a home for a number of large locos, which whilst not necessarily being suitable for main line work, deserve to be restored on their own merits. Is there really the work for such a machine anyway, I think its difficult to say given the current climate The question of 90 mph certification is already quite well discussed- are the benefits of running at these speeds really going to outweigh the associated problems, and if they were would the A1 guys not be pushing harder for it already with Tornado?

As already mentioned a long way back in the posts, Blue Peter and Green arrow are waiting in the wings crying out for another chance to shine- I for one would be more keen to see these former main line stars re emerge!

2) Creating a new P2 doesn't actually seem to be the aim of the project and as such I'm not sure how keen I would be to support a new build, that essentially sounds as though it will be a new design, and a fairly radical departure from the original.- I cant help but think that this would likely end up as a larger 5AT masquerading as a heritage loco, and this idea doesn't sit quite right to me!


As regards the debate on Thompson-Gresley-Peppercorn, Thompsons pacific creations are not the prettiest machines but who are we to say about their performance? All I can surmise about them is that unlike the Castles/A4s/Coronations etc which were raved about, they surely cant have been 'all that' otherwise surely it would have been documented in a similar vain at the time.

Anyhow, thats my threepennies worth!

Chris

 

Agree on all fronts. The heart says a P2 would be nice, but the head says probably better to create something of more practical use. Green Arrow is not going to run again because of the cylinder block, so maybe better to have a replica V2 than a new P2. Or a B17 which would be of similar capacity, but someone is already working on that.

 

There's bit of a difference between a freight 2 - 8 - 2 and a passenger one - the P1 class had 5ft 2 in drivers (as the K4) instead of the 6 ft 2 in of the P2 and the fixed wheelbase was 18ft 6in against 19ft 6in of the P2. Personally I'd be fascinated to see a P1 (basically an A1/A3 with smaller wheels - can anyone say newbuild A3 using common parts?) but I doubt there would be the interest.

It's true that if sufficient people are prepared to fund a hybrid Mikado, why not, but then it isn't a P2 if significant changes are made beyond those made in service.

Perhaps the 5AT should be reconfigured as a mixed traffic mikado - a P1/P2 synthesis (without the sad attempts to make it look modern)

 

Hang on, I'm getting confused. You ask if these 'improvements' are really necessary, then you list them and go on to justify them? Also there seems to be an intimation in your and other posts that there will be many other changes that will result in something that bears little resemblance to Gresley's P2? The mods that you mentioned won't affect the outward appearance to any significant degree, and the Caprotti gear only slightly. So what are these other more controversial mods? I'm not aware of any such proposals. The only detail I can think of that might pose a problem would be the feed heater and pump if not fitted, but that was removed later anyway, so its omission could be considered valid.

 

Sorry Sheff, I haven't made myself very clear. I wrote in response to the idea a bissel truck would be considered, aired earlier in the thread, and I - personally - think that would change the look of the front end too much.

I do think Caprotti valve gear is a logical and sound development.

 

I suggest we await the outcome of the dynamic modelling before setting too many hares running and turning people off before the project's even got the green light. Current intention I believe is the later design V2 truck IF it passes the simulation.

 

Fair enough Sheff, my apologies once again.

 

Re the Ongar Finnish 2-8-2, surely not beyond the bounds of possibility to dismantle it, close up the frames and shorten the axles (probably new ones needed) by 3-1/2" to convert it to standard gauge? Subject to its overall condition, that is.

 

Erm, that's Atlantic singular, not Atlantics. There was only one sleeve valve Atlantic, and it was the Leader testbed - your post rather implies it (they...) were a design in their own right.

But let's not get a thread about the P2 onto the relative merits of OVSB! Though it is interesting that however he polarises opinion and whatever he did in rebuilding Maunsell's designs, there doesn't seem to be anywhere near as much heat and light as is generated by the Thomson / Gresley / Peppercorn saga.

Tom

 

I believe the NVR looked at doing just that but they deemed it not cost effective.

 

Bulleid's modifications to the Nelsons transformed their performance so it would hard to argue against the changes he made. Plus it wasn't a wholesale rebuilding a la 4470 and the locos looked much the same post modification as pre modification. Equally the mods he made to some of the Arthurs and Schools were just front end changes and not major rebuilds.

 

But the whole thing is too big for the UK loading gauge - IIRC only the NVR & GCR can take Berne Gauge stock...

Anyway, back OT - I look forward to hearing the results of the simulations that are being done. Once there is a 'yea' then we can move forward. The alternative, of course, is a 'no' - let's not go there...

 

Ha ha - instant 7 page thread - just add wibble

 

If its a no then we go back to the 'what next ? ' debate
Is everyone keen for another Peppercorn A1 ?
Newbuild V2 ? HUSH HUSH ?

 

I'd agree with you on a newbuild V2, but what about a K3?