Standard 7mt 2-8-2 Mikado

Probably because of the restricted British load gauge profile which seriously limits the widths over cylinders, particularly low down. Note how cylinders on 9Fs are inclined up at a greater angle than other Standards for this very reason. This overall width restriction limits the clearances between rod centres and wheels given that bearings for connecting and coupling rods have to be fitted in, this in turn limits the amount of side play as to make the fitting of a Krauss-Helmholz rather pointless. Bear in mind that a 9F is only 8' - 10-1/2" over cylinders, compared with a DR Kriegslok BR 52 at about 9' - 10" (3 meters) and you'll see what I mean.

 

Brilliant ! thanks very much.
(ps theres only 1 copy left now

 

whilst not totally in keeping with the design wouldnt it be easier to use an ex barry 9f as the base of the design and re design it as a 2-8-2 using the 9 f boiler with new firebox end frames to take a trailing truck coppied from a britainia? i know that its not totally right but you would have in essence a 2-8-2 version of a 9f which is what the plan was and with the tire less middle driver problem removed ,you could have the heavy haulage capability without the engine being no good for main line if that was the plan

 

No prob. I bet you bought the twenty quid copy, not the fifty-six quid one!

 

The idea with the British standards is that they we re simple machines using the best existing (british) practice. The 9f was already the most radical departure from this.
Although the above might have increased route availability, there were already plenty of eight coupled engines available where this was a concern. This particular mod couldnt justify itself on fuel or maintenence savings ( the reasons behind the Crosti and geisl mods)and , in short, he didn't need to...

 

Probably cost. Also Riddles was (in)famous for wanting simplicity regardless of the performance cost. If it wasn't for the restricted UK loading gauge we could perhaps have borrowed a 2nd series 141R, a simple enough design but the quality of some of its design features would have given Riddles a fit. The performance of the loan machine would have given him another. We couldn't have afforded to buy them though even if we could have used them.

 

This is one ive toyed with quite a bit, (indeed if you wanted to make this hybrid you could probably even use the back end of a Bulleid) and at this point the bit thats most off putting is that it looks odd ( see 00 mockup earlier on this and thats not top be scoffed at) and its only got 5 Ft drivers.( Limited to 50mph) whereas with the true original design you did get 5ft 3's (5% difference, wow) maybe even possible to squeeze in 5ft 6's...
Im sure it could be made to work Martin but the raw materials themselves must be fairly tired and old... and how long would it last ?
I think the true appeal of the design apart from the unique wheel arrangement (what p2 ?) is the 'If only/ what if' factor: as a half way stage between two decent engines, the Brit and 9F, would you get the best of both worlds and get the 'Ultimate' mixed traffic engine...

 

The 2-8-2, if it had been built, would have been simply a Britannia with a different wheel arrangement. A 9F is not. So adapting a 9F would actually produce a further new design.

I think given the state of the ex-Barry 9F's that remain 'untouched' a new build would be a better bet if the intention is to try out the original design - however, if someone chooses to save one of the unwanted 9F's they might well aim at a 2-8-2 conversion as being more useful - could it have all flanged wheels and thus be 'mainlineable'?

 

By using the boiler and cylinders from an 9f wouldnt that reduce the ammount of money needed? after all, how much would a new boiler cost? compared to rebuilding an exsisting boiler thats got to be in reasonable condition when you think how short a life they had? that way you would only need new frames then theres the wheel size, isnt there a dispensation if the ballancing is better ,i believe that carnforths 8f can run at 75mrh because of this fact

 

Both the above correct, i tend to agree that a new build, given the no of existing or shareable patterns, is the most forward thinking:
even if the Mikado was the only one built (though two would be nice: Bond & Cox) the lives of our two brits, and or a new one and or a new Duke (Riddles) would become much more affordable/ feasible as a result.
The most expensive bit is going to be the boiler and theoretically you could marry an old 9f boiler with a clan firebox, (a bit under sized and you would need some porta style combustion mods to get enough energy out) or design a new firebox with more grate area and ashpan (as there would be room for it now) to suit. But once youve done all that (and at the risk of producing a something that needs a whole new draughting arrangement working out) , you are not much short of an all new steel boiler from Germany

Carnforths 8F is permitted to run at 50mph due to its 'improved' balancing. But If Tornado gets the regs re written to run at 90mph
then a new something with 5ft 3inch wheels, appropriately balanced should be allowed 70mph

 

My thoughts would be to build two 2-8-2's..

One in as close to original form as possible, and using the same frames / boiler design to improve on it using modern technology and the last 40 years knowledge, ie. Giesel Ejector, Porta's suggested A1 enhancements, mechanical firing, maybe even computer managed boiler water levels and firing ? who knows maybe even a new "BR1L" ? tender.. (an 8 wheel extended water capacity creation .. and maybe examine carbon capture technology.. it's worth applying for a grant

 

The Polish PT47 class are quite a capable loco, I had the pleasure of a couple of hundred miles on the footplate last year at Wolzstyn. They are from a similar era to the BR Stds and were a passenger loco rather than mixed traffic but would make an interesting comparison with features mentioned prviously -mech stoker, large 8 wheel tender(although PT47-65 has a smaller 8wheel tender so it fits on the table at Wolzstyn)
The cabs and tenders are also reminiscent of the BR stds with the backsheet to enclose the cab and the raised coal space.

 

pt47 were introduced in 1947.
Hence the class number, there are a derivative of the pt31 class, which 54 had been built by 1939.
The DRG found them most agreeable, even better than their own BR 19 2-8-2and relocated most of the pt31's from Poland to the mountains in Austria, Czechoslovakia and Hungary as class BR 19.1 and ordered additional construction of the 56 further examples of the class, in preference to their own BR19 during the war.

After the war less than half remained in Poland, and even less operational. Some pt31's had even been regauged and based in Lvov, after the city was transferred to the Russians.
With such a shortage, and a few minor modifications, the pt47 was created.

The DR/DB BR 41 also owes much of it's design to the pt31 and Poles are rightly proud of their express mountain climber.

Today 2 pt31's remain in Poland. (the only mechanically complete one being in Chabowka).
1 pt47 was sold to OEGG (Austrian railway preservation group) and by by modifying the smoke deflectors and the central dome have effectively recreated an original form pt31, but as as OBB 919 class (post war Austrian BR19.1/pt31 classification). This worked a number of railtours for many years.

For comparision, pm36-2 (Wolsztyn operational) is a 4-6-2 experimental offering of the same pt31 design.

After seeing a few operational pt47s, the static pt31 and more recently seeing 41.018 and 41.360 in action... I am a firm fan of eastern european 2-8-2s.

 

I did realise that the PT was a little earlier than the BR Stds so maybe not quite the same era.

47-65 was a nice loco to drive and rode well. I did struggle getting coal to the front right corner of the box though having a redundant mech stoker in the way didnt help.

Seen in action here http://il.youtube.com/watch?v=f3gDVGMjBdA

 

Do you have any details on this Polish locos 'Spec' ?
I ve heard that aBulleid 2-8-2 design was reasonably advanced but, turned down by SR Permanent way. Are there any surviving drawings ?

 

OVSB's first proposal for what became the Merchant Navy class was a 2-8-2. Most of the books about his locos mention the proposal and the civil engineers' objections. I guess they'd heard about the problems with the P2...

 

According to Sean Day-Lewis's "Bulleid - Last Giant of Steam" pp 140 - 141, the Civil Engineer George Ellson was unhappy about the weight and disliked the idea of a leading pony truck, having been involved with the Sevenoaks disaster. He is said to have reluctantly agreed to Bulleid building two 2-8-2s for testing. Bulleid feared that such tests could go on for years, so cut his losses and opted for a Pacific.

 

Here's a link to the pt31 here

http://www.locomotives.com.pl/Express%20Steam%20Locomotives/Pt31.htm

I have attached some scale drawings here of the pt47, they are pretty much externally identical, apart from the Tender and some minor enhancements to the boiler and a more square smoke deflector...

http://www.interlok.info/Pt47.htm (to credit the source site).

 

a Bulleid 2-8-2 sound's quite interesting I'm curious what one would of looked like.

 

Re. the interlok.info page, can you tell me how much 1kN of tractive effort is in lbs?