group wants to build new PRR T1

[miyakoji]

Some of you may be familiar with the A1 Steam Locomotive Trust's work to build 60163 Tornado, a newly-built Peppercorn class locomotive.  The result is fantastic.  In the US, a similar group has formed to build a new Pennsylvania Railroad T1, number 5550.  They estimate it will cost 10 million US dollars to build it.  I hope they're successful, I'm a bit surprised that not a single one of the originals was preserved, running or otherwise, all were scrapped.

 

 

http://en.wikipedia.org/wiki/PRR_T1

http://prrt1steamlocomotivetrust.org

http://en.wikipedia.org/wiki/LNER_Peppercorn_Class_A1_60163_Tornado

http://www.a1steam.com/

[katoftw]

Wow thanks for that.  Never knew this stuff was happening.  Was interesting to see the modern day changes like roof lines and tedner inturnal redesigns also went into it.  No more running through puddles scooping up water.

[miyakoji]

They have cast a driver (boxpok, a new word for me :)): https://en.wikipedia.org/wiki/File:The_T1_Trust_Boxpok_Driver.jpg

 

edit: There's video of the casting process.  No view of the wheel, though

 

 

Also, in the comments of that video there's a bit of discussion about the T1's anti-wheelslip capability.  I didn't know that steamers have traction control :)

Edited June 12, 2016 by miyakoji

[kvp]

Anti wheelslip in this case meant distributing the weight evenly. In case of the T1, the prototypes could lift their 4 drivers off the rails on rougher rails thanks to their rigid mounting. For the production run, they were equalized to the pony trucks, so the pony trucks couldn't take off too much weight and lift the drivers.

 

Alternative designs had the pony trucks mounted on the same moving frame as the drivers or in one case got rid of the ponies and used more drivers to have all weight on the drivers. Since for the T1 speed was more important than starting power, this unique unarticulated 4-4-4-4 design was used. I wonder though what do they plan for the poppet valves as the original design was prone to breaking at full speed.

[bikkuri bahn]

Not to disparage the efforts of the enthusiastic, but I find it ironic that money is being spent in a country to recreate a high speed steam locomotive (and a possible attempt at a speed record- where? NS restricts steam locomotives to 30mph on their track and preserved/heritage railroads aren't speedways), when same country is having difficulty in building an actual high speed rail line that transports ordinary people rather than railfans and people pining for the old days.

*btw, I have contributed money to a steam locomotive restoration (an ATSF 2900 class Northern type in Pueblo, CO), unfortunately, that attempt did not pan out. 

Edited June 13, 2016 by bikkuri bahn

[velotrain]

_{Tornado was started in 1994.  Materials and labor costs have increased quite a bit in the past two decades.}

 

_{Also - I'm quite sure there is a far wider public backing for railway projects in England - where there are many preserved lines, than in the U.S.}

 

_{This seems as likely to happen as Texas high speed rail.}

[tossedman]

They have cast a driver (boxpok, a new word for me :)): https://en.wikipedia.org/wiki/File:The_T1_Trust_Boxpok_Driver.jpg

 

edit: There's video of the casting process.  No view of the wheel, though

 

 

Also, in the comments of that video there's a bit of discussion about the T1's anti-wheelslip capability.  I didn't know that steamers have traction control :)

 

Now that looks like thirsty work! I need a beer just watching it.

[marknewton]

I didn't know that steamers have traction control :)

They do. It's otherwise known as the driver. :)

 

Over the years there have been a number of well-written, well-researched articles on the T1s published in the PRR historical society's journal. In my opinion they have debunked many of the myths surrounding their performance, and in particular their alleged propensity to slip uncontrollably. When driven by an inexperienced or less-than-competent engineman, any steam loco can slip badly. Practice, experience and skill of the crew are the most significant factors governing any steam locos performance.

 

Talking specifically about the T1s, I'd point out that between the regulator/throttle valves in the superheater header and the valve chests of the cylinders there's about thirty feet of large diameter steam delivery pipe. So even if the driver was very quick to react to a slip by closing the throttle, there's still a substantial volume of steam downstream of the throttle that will continue on its way to the cylinders. So arresting the slip becomes that much more difficult.

 

The same problem was evident on the Pennsy's freight duplex engines, the Q2s. To help minimise slipping they were fitted with a slip control device. It was an electro-pneumatically controlled butterfly valve in the steam delivery pipe downstream of the throttle. The idea being that it would detect the difference in speed between the two engine units if one slipped, and shut off steam to the engine slipping. Apparently when it worked it was effective enough, but they were unreliable and often failed. From memory a few T1s were also fitted with this device, but it was too little to late.

 

A more practical approach to the problem was to fit liners to the cylinders to reduce their bore, thereby reducing the engine's tractive effort and improving the factor of adhesion. It was effective, but again too late to make a difference.

 

I've often thought about the T1s. In my view they were a design with tremendous potential, but they were built at the wrong time for the wrong railroad. As an engineman I think running one would have been a tremendous experience - challenging no doubt, but satisfying if you were to master it.

 

Cheers,

 

Mark.

[kvp]

A reliable way to limit a slip is to fit mechanical speed measurement on the first driver and the last non powered wheel before it. If the difference exceeds a preset value on a differential arm, the arm actuates two valves to shut off (or proportionally limit) steam at the cylinders. This lets an unexperienced driver or one that is remotely controlling from a driving car control the throttle without checking for slip. (useful for push-pull or multiple unit operation)

 

For the PRR T1-s, i read that when they changed the driver equalisation on the production locomotives to depend on the nearest non powered trucks instead of between the two driver groups (similar to mallets) they became easier to drive and could also provide higher starting force.

[brill27mcb]

From videos I have watched, it seemed to generally be the front set of drivers that slipped, and usually on leaving a station. I can also see how if one set slips, it can over-stress and "break" the traction of the second set and can set off an unstable dynamic on the whole engine until things get settled down again.

 

I agree, the T1 articles in PRR T&HS "The Keystone" are very well done, although almost a crusade/obsession of the author's. The one I found most interesting was the one with multiple engineer/fireman stories about top speeds that eclipsed Britain's Mallard "world record" for steam speed. Of course, the T1 speeds won't be considered "official" because they were not purposely staged events with British train-timers aboard with their stopwatches and track charts.

 

Rich K.

[kevsmiththai]

Tornado was just the tip of the iceberg in the U.K

 

 

Flushed with the success of the LNER Peppercorn A1 pacific 'Tornado' and the two replica Great Western broad gauge locos 'Iron Duke' and 'Firefly' groups up and down the country are now steaming ahead (If you'll pardon the pun) on the following amazing list of projects
 

• Baldwin Lyn 2-4-2T 762 Baldwin 2-4-2T Lyn
• BR Standard Class 2 2-6-2T 84030 project
• BR Standard Class 3 2-6-2T project
• BR Standard Class 3 2-6-0 77021 project
• BR Standard Class 6 4-6-2 72010 Hengist project
• GCR Class 2 (LNER Class D7) 4-4-0 567 project
• GER Class H88 (LNER Class D16/2) 4-4-0 8783 Phoenix project
• GER Class M15 (LNER Class F5) 2-4-2T 67218 project
• GWR County 4-6-0 1014 County of Glamorgan project
• GWR Saint 4-6-0 2999 Lady of Legend project
• GWR 4709 2-8-0 project
• GWR 6800 Class 4-6-0 Betton Grange project
• LB&SCR H2 class 4-4-2 project
• LMS-Patriot Project 4-6-0 5551 The Unknown Warrior
• LNER Class B17 4-6-0 61662 Manchester United project
• LNER Class B17 4-6-0 'Sandringham' project
• LNER Class P2 2-8-2 2001 Cock O' the North project
• LNER Class P2 2-8-2 2007 Prince of Wales project
• LNWR George the Fifth Class 4-4-0 project
• NER Class O (LNER Class G5) 0-4-4T

Obviously some are more advanced than others but many of these locos are making considerable progress

In addition another group is planning a recreation of the pioneer LMS Co-Co diesel electric 10000!

 

Some of these locos are being redesigned from the original to have space for the TPWS and GSMR electronics to allow full main line running

 

The Patriot 4-6-0 'Unknown Warrior'

 

 

Standard tank

 

 

GWR County 4-6-0

 

 

With the huge growth of revenue of preserved steam lines and the willingness in the U.k to run main line steam on the network the business case for many of these new builds is sound. The skills base to produce these locomotives is also growing and specialised foundries, machine shops and boiler making firms are working flat out to keep up with demand.

 

Current progress, as of a couple of weeks ago is.

 

2-4-2T Lynn has had wheels and axleboxes trial fitted at Alan Keef's works and has a target date for steaming in may 2017

 

Unknown Warrior was having its cylinder liners fitted  and boiler work ongoing

 

County of Glamorgans tender is well advanced

 

the 47XXX group only need £18,000 raised to complete all of the work on the wheelsets

 

The G5 group now have a complete smokebox to display

 

The P2 'Prince of Wales' mikado group have now raised 44% of the £5 million needed and has virtually completed the unique smokebox arrangement and the frames are having the stays and hornblocks fitted

 

I'll keep you posted on progress as they carry on

 

Kev