P2 Locomotive Company and related matters

No disrespect but we've gone through this ad infinitum on the ET thread. Do we have to go over old ground yet again on this thread? Let's celebrate the fact we're getting a P2.

 

Hence why I said "that's for another thread"...

 

Fascinating...I have learned something! Thank you

As for 163 in apple green - I was aware that it had happened very briefly. Nevertheless, I'd love to see her actually running in that guise, with a rake of teak coaches behind the tender. I can quite understand that, for marketing purposes, it is better for the A1SLT if her normal running number remains consistent as 60163. Nevertheless, if the LNER option were to, say, be offered for a photo-charter, I'd be very tempted!

 

The trust thinking is that as 60162 was built after Nationalisation the next in the series had it followed immediately would have carried the same livery, Apple Green with BRITISH RAILWAYS on the tender. It still looks great and perfectly realistic on a set of teaks whch would have remained so for some time after 1948

 

In all honesty, had a further batch of A1s appeared they would have most likely have been express blue, as per a number which were actually delivered in that livery. The apple green livery is technically therefore unlikely for any 60163: but how can you not use it when the class wore it so well? It represents the originals as much as it is its own locomotive, Tornado, and that's why I love it.

I'm in a tiny minority where one day - if only for a week, a month, or whatever - but temporarily I'd like the stovepipe chimney restored, a new smokebox door with the original style numberplate in the higher position (curly sixes and all) and the Darlington style of lining out on the tender, just to offer something that extra bit closer to the original engines. I totally respect the trust's desire to keep the "brand" and image of the loco consistent, so it'll probably never happen, but even so I'd love to see it...

 

Careful, I got flamed for daring to say the same thing about the P2

Dave

 

New smokebox door not necessary; just move the numberplate above the handrail.

 

Since I am feeling in a puckish mood, the question I would ask about No. 2007's future livery would be, "Doncaster green or Darlington green?"

Simon, for your pleasure,

Foxy

 

Love it. Everything looks good in apple green!

 

Also: Doncaster green. None of the P2s were painted in the darker Darlington shade. But then Tornado is Darlington built and also in Doncaster apple green, so a precedent was set there

 

Further progress has been made with the frames and the design of the frame stays. A huge amount of work has gone into the CAD designs, turning castings into fabrications, adapting them for different roles and stress testing them in virtual reality, all of which needs to be recorded and paper-trailed for the big railway. You can see an update here.

Foxy

 

Good to see from the linked piece that the fabricated stretcher CAD models appear to have full penetration welds, nice detailed modelling. Out of interest, what sort of inspection regime does a welded stretcher have to go through to gain acceptance for use on the main line? Mag particle, x-ray, whatever? I'm taking as read that the welders have to be coded for the joints in question.

 

Some very fine modelling there. I hope you put up some of the FEA FOS or Von Mises simulations at some point.

I don't have the official answer to this, but from what I have seen on other projects its usually B&W MPI. I would be surprised to see Radiographic for this...but I could be wrong.

 

As well as 'virtual' construction and design, work is forging ahead with patterns and castings, we now have a complete Kylchap pattern.

Foxy

 

Hey foxy, are you using the same geometry for the Kylchap as Tornado ? (im guessing that this is the same as Blue Peter ?)

 

I'm no expert but there is an agreed formula for calculating the proportions of a Kylchap assembly which may well be dependant on the cylinder size - can anyone help? Otherwise I'll try to get an answer.

Foxy

 

Hi, as far as I am aware there is no published calculation method for a Kylchap. Since Chapelon was still alive when they were
designed for BR there was no need. If someone needs a calculation, I would suggest using the methods in "The fire.." for sequentially positioned "chimney" systems. I tried once and it seemed to give usable results, however, never compared to real life data.
Kind regards
Jos Koopmans

 

Jos, I have a copy of "The fire.." Could you please direct me to which section of the book the calculations for sequential sections are in.
Thanks and Regards

 

I attended the project's presentation at the Festival of British Railway Modelling at Donny yesterday. It was well done and very interesting technically, such as the corners of the foundation ring being cast to stabilise stresses in that area, that the Lentz gear will have the USA Franklin modifications, and that the cylinders will be made a smaller internal diameter compensated by higher boiler pressure plus of fabricated steel to make them smaller than cast ones to meet NR platform edge to rail standards. Also the crank axle will be 10" diameter to hopefully avoid failures partially caused by the fact that an eight coupled loco is less likely to slip so you are putting more torque into the mechanism. They rejected the A4 front end as it would look like an A4 gone wrong(!), but the original design should lift the smoke sufficiently. A little bit of anti Thompson feeling came across, perhaps not surprisingly (and ignoring the fact that ET did what Gresley didn't and produced a large fleet of go anywhere mixed traffic locos) but overall very professional. You can view the progress at Darlington on every third Saturday.

The Doncaster P2 folk had a stand as well - but not on the same floor.

Dave

 

It is the Saunders Idealised theory page 461 for each of the separate parts of a Kylchap. There is a caveat because the output of the earlier stage is the input of the one under calculation. This is for the results of a momentum calculation only.
If dimensions are needed it is simpler: use the formula of Ell for a single chimney. If it is a 3-cylinder realise that the formula is biased because it treats 2/4 and 3-cylinder locomotives equally. Diminish to say 95% of the calculated diameter. The dimensions of the intermediate contraptions can be scaled from an existing Kylchap. If a double is needed one should realise that statistics tell us that each of the orifices of a double Kylchap had the area of the original simple single, so the blast area is doubled.
If I had a say I would simplify the Kylchap drastically. It carries the unproven claim that it sucks at all levels, so what? All entrances of a Kylchap have cones instead of a trumpet entrance with a radius and better entry coefficient. Furthermore, Goss proved around 1902 that all these intermediate tubes did not really gave an improved result. Above all, the double chimneys are an enigma, why not combine them
into a single oblong one? Would save friction from a diminished wall area.
Looking that way it evolves either in Giesl or Lempor alikes.
Kind regards
Jos Koopmans