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PRR 4-6-4

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PRR 4-6-4
Posted by oltmannd on Thursday, December 25, 2008 10:04 AM

A 4-6-4 on the PRR would be a P class, but they certainly wouldn't have let a 4-6-4 steam locomotive be called a Hudson anymore than the NYC would let a 4-8-2 be called a mountain. So, if you were the PRR, what would have called a 4-6-4?

How about a "Juniata"?

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Posted by ndbprr on Thursday, December 25, 2008 10:58 AM

It wouldn't necessarily have been called a P class.  The letteres were assigned in order of design and production so you jump from E to G to K from a 4-4-2 to a 4-6-0 to a 4-6-2.  I doubt the PRR would ever have had a 4-6-4 as they used 2 wheel trailing trucks up until the very last engines.  It was the borrowed J class engines of C&O design that got them into four wheel trailing trucks.  I don't recall an "O" class and it could have stood for "Oddball".

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Posted by feltonhill on Thursday, December 25, 2008 7:45 PM

 Which J class C&O loco did PRR borrow?  I recall they tested an N&W Class J in Dec 1944 but that was after the first two T1's and most of the J1 2-10-4's were on the road.

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Posted by tomikawaTT on Friday, December 26, 2008 10:37 AM

What was borrowed on the PRR J class was the C&O design - the War Production Board wouldn't let Altoona experiment with scarce steel and limited manpower resources, so mandated that Pennsy would have to build to a proven design.

IIRC, the 'borrowed' 2-10-4s were Santa Fe locos.

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Posted by oltmannd on Friday, December 26, 2008 9:56 PM

ndbprr

It wouldn't necessarily have been called a P class.  The letteres were assigned in order of design and production so you jump from E to G to K from a 4-4-2 to a 4-6-0 to a 4-6-2.  I doubt the PRR would ever have had a 4-6-4 as they used 2 wheel trailing trucks up until the very last engines.  It was the borrowed J class engines of C&O design that got them into four wheel trailing trucks.  I don't recall an "O" class and it could have stood for "Oddball".

Well, the PRR electrics followed their steam class numbers, e.g. DD-1s were 4-4-0s, GG-1s were 4-6-0s, P5s were 4-6-4s, the R1 was a 4-8-4.  So, I figured a 4-6-4 steam locomotive would be a P class.

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Posted by beaulieu on Friday, December 26, 2008 11:31 PM

tomikawaTT

What was borrowed on the PRR J class was the C&O design - the War Production Board wouldn't let Altoona experiment with scarce steel and limited manpower resources, so mandated that Pennsy would have to build to a proven design.

IIRC, the 'borrowed' 2-10-4s were Santa Fe locos.

Chuck

 

The borrowed 2-10-4s were C&O T-1 class locomotives, a product of the Van Sweringen Road's "Advisory Mechanical Committee", the same people who created the Nickle Plate Berkshires and all of the C&O's modern steamers.

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Posted by erikem on Saturday, December 27, 2008 12:48 AM

oltmannd

Well, the PRR electrics followed their steam class numbers, e.g. DD-1s were 4-4-0s, GG-1s were 4-6-0s, P5s were 4-6-4s, the R1 was a 4-8-4.  So, I figured a 4-6-4 steam locomotive would be a P class.

 

Sounds reasonable to me. A minor correction, the GG-1's were the equivalent of two 4-6-0's back to back, hence GG-1 as opposed to G1. Had the PRR bought some Challengers, they would have also been GG's (GG-2????). 

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Posted by daveklepper on Monday, December 29, 2008 4:51 AM

And I think you are correct.   A PRR Hudson would have been a P-something.   DD-1's were two 4-4-0's back to back, GG-1's were two 4-6-0's back to back.   The B-1 switchers were electric and the B-6's were steam (slope-back tenders, also used by Washington Union Terminal until the Alco's arrived), both 0-6-0's.   So you are  correct.

 The PRR did not need four-wheel trailing trucks to support large fireboxes, because of its excellent heavy track structure.   The PRR equivalent to the first Hudsons was the K-5, which was a good design, but was not built in quantity because of electrification .  The K-5 could perform as well as the J-1 Hudson.

The duplexes had four wheel trailing trucks, the T-1 and Q-1 and Q-2. 

 

The PRR J-1, was the C&O's 2-10-4 Lima design, but with the booster omitted.  It was a poor choice in many people's opinion, because the work it did could just as easily have been done by the old reliable 2-10-0's!   But the crews liked them because of more pay (heavier) and more comfort.

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Posted by feltonhill on Monday, December 29, 2008 6:37 AM

 PRR 2-10-4's had boosters as built.  Some may have been removed, although all photos I've seen indicate the presence of a booster.

I doubt the I1's could come close to duplicating the same goss ton-miles per train-hour that  J1 could generate.  We're comparing a 3,000 DBHP @ 25 mph loco with a 5,000 DBHP @ 40 mph loco (DBHP at rear of tender, not on Altoona test plant). 

Can't blame the crews.  Can you imagine enduring the rough ride of an I1 for an entire division?

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Posted by tpatrick on Monday, December 29, 2008 8:13 AM

beaulieu
The borrowed 2-10-4s were C&O T-1 class locomotives, a product of the Van Sweringen Road's "Advisory Mechanical Committee", the same people who created the Nickle Plate Berkshires and all of the C&O's modern steamers.

 

You are correct about the borrowed design of the PRR J class. But Chuck is correct, too, because PRR did borrow SF 2-10-4s to run on their Sandusky line. It all depends on how you apply the word "borrow." 

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Posted by selector on Monday, December 29, 2008 12:25 PM

There were two vesions of the J1.  At least one version had boosters.  The J1's produced nearly the tractive effort with their two cylinders that a UP Challenger did with four (not so for the NP's versions which were substantially more powerful).  I hardly think the J1 could be matched by a mere 2-10-0.

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Posted by The Dude With The Hair on Monday, December 29, 2008 3:05 PM

daveklepper


 The PRR did not need four-wheel trailing trucks to support large fireboxes, because of its excellent heavy track structure.   The PRR equivalent to the first Hudsons was the K-5, which was a good design, but was not built in quantity because of electrification .  The K-5 could perform as well as the J-1 Hudson.

 

 From what I read the performance of the K-5 was not satisfactory, or at least not enough to justify building more. They had power but lacked the factor of adhesion necessary to reliably apply that power to the rails. They weren't sure-footed like the K-4s were. If they'd put an extra pair of driving wheels on them to ensure better traction I'm sure they would have been excellent performers.

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Posted by daveklepper on Tuesday, December 30, 2008 5:06 AM

My understanding was that it (only one was built) was successful, and adhesion could have been improved by adjusting spring rates and equalization, but electrification and only electrification doomed the project by eliminating the need for more steam locomotives.  I guess it depends on whom we have heard!   The PRR J was a fine locomotive, but it was not used where its superior ton-miles per ton of coal performance could shine.   I understand it was mostly used in helper service, and did not have the opportunity to outperform a 2-10-0 in that particular service, being actually less economical to operate.  Why the PRR didn't exploit its capabilities better is a very good question.

I did not know that the PRR J was built with a booster.  In my experience the only ones I ever encountered must have had them removed at a maintenance shop visit.

 

Possible names of a PRR  ---and why didn't they give a T-1 a name?    Juniata for shure, but also Keystone, Apaplachian, Princeton, Liberty, Carneige, Brynmore, Norris, Gibbs, Atterbury

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Posted by feltonhill on Tuesday, December 30, 2008 6:17 AM

 There were two K5's - 5698 and 5699.  5698 was built with Walschaerts valve gear and 5699 had Caprotti poppet valves.  They were not successful and were eventually removed.  The only credible history I know of was written by Charlie Meyer in the Winter 1995 Keystone, pgs 13-30, published by PRRT&HS.  Their main problems seemed to center around poor steaming and drafting, probably interrelated.

I don't know where the info came regarding the use of J1's in helper service.  I believe th the source may be questionable  Every photo I've seen where they were used (which is pretty much anywhere west of Altoona on the main lines) shows a J1 or two up front and an I1 or two pushing when required.  I've never seen or heard of J1's being regularly used as helpers, except as part of a double header north out of Columbus.  They are generally acknowledged as one of the most successful locomotives PRR ever had.

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Posted by daveklepper on Wednesday, December 31, 2008 2:51 AM

J's:  I respect your sources as more auhoritive than what I heard.   Possibly the hoggers I heard were talking about use of the Pennsy J's after most road power was diesel and the J's had been demoted, but they didn't tell me that.  

 

K-5's:  However, the source that told me that the K-5 project was dropped only because of electrification and for no other reason was reliable.  The main point is that if the track structure can take the weight, and for many years the heavierst rail in use in North America was found only on the PRR, there is not necessarily an advantage in using a four-wheel trailer truck as compared with a two-wheel.   Note that the "Apex of the Atlantics" Kalmach book says the PRR dropped a super Atlantic project for the same reason.   Hopefully someday there will be companion K4 book, and I think the locomotive deserves it.   Then, all information on the K-5 development and its termination will be at hand.   One of the K-5's received modifications, forget what they were, as was used successfuly for a number of years.  Possibliy that is why I had forgotton about the one that was retired early.

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Posted by dknelson on Sunday, January 4, 2009 6:35 PM

The Milwaukee Road, which actually had steam 4-6-4s, did not refer to them as Hudsons but rather as "Baltics."  I seem to recall there was European precedent.

Perhaps the Pennsy would have used that same terminology as it would both avoid referring to their NYC rival and also avoid making it clear they were avoiding referring to the NYC. 

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Posted by wjstix on Tuesday, January 6, 2009 10:38 AM

Keep in mind the nicknames of various engine types were just that - nicknames, often unofficial. There was no government agency regulating it or anything.Smile,Wink, & Grin

Yes a few railroads like NYC promoted use of certain nicknames for some of their engines, and some railroads tried to give different nicknames to certain types of engines (like the Milwaukee's failed attempt to get "Baltic" to catch on for 4-6-4's, or southern railroads calling 4-8-4's "Dixies" instead of "Northerns"), but others didn't really care. I suspect if the PRR had 4-6-4's they wouldn't have nicknamed them anything.

In any case, most working railroaders referred to their road's engines by their letter-class designation or their number series, not by their nicknames. I believe UP guys called the railroad's 4-8-4's "800's" for example, based on the engine's number series.

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Posted by JonathanS on Monday, January 19, 2009 8:38 AM

oltmannd

ndbprr

It wouldn't necessarily have been called a P class.  The letteres were assigned in order of design and production so you jump from E to G to K from a 4-4-2 to a 4-6-0 to a 4-6-2.  I doubt the PRR would ever have had a 4-6-4 as they used 2 wheel trailing trucks up until the very last engines.  It was the borrowed J class engines of C&O design that got them into four wheel trailing trucks.  I don't recall an "O" class and it could have stood for "Oddball".

Well, the PRR electrics followed their steam class numbers, e.g. DD-1s were 4-4-0s, GG-1s were 4-6-0s, P5s were 4-6-4s, the R1 was a 4-8-4.  So, I figured a 4-6-4 steam locomotive would be a P class.

You are certainly correct.  The Pennsy had 2-8-2 steam and electric locomotives that were both considered L classes.  Additionally, they had steam and electric 0-6-0 locomotives and both were B classes.

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Posted by tomikawaTT on Monday, January 19, 2009 1:02 PM

JonathanS

oltmannd

ndbprr

It wouldn't necessarily have been called a P class.  The letteres were assigned in order of design and production so you jump from E to G to K from a 4-4-2 to a 4-6-0 to a 4-6-2.  I doubt the PRR would ever have had a 4-6-4 as they used 2 wheel trailing trucks up until the very last engines.  It was the borrowed J class engines of C&O design that got them into four wheel trailing trucks.  I don't recall an "O" class and it could have stood for "Oddball".

Well, the PRR electrics followed their steam class numbers, e.g. DD-1s were 4-4-0s, GG-1s were 4-6-0s, P5s were 4-6-4s, the R1 was a 4-8-4.  So, I figured a 4-6-4 steam locomotive would be a P class.

You are certainly correct.  The Pennsy had 2-8-2 steam and electric locomotives that were both considered L classes.  Additionally, they had steam and electric 0-6-0 locomotives and both were B classes.

Have to contradict ndbprr.  The PRR letter designations for locomotive classes were, in fact, logical and based on wheel arrangement.  See the table on page 5 of Westcott's Steam Locomotives.  The logic was skewed (Taking the sequence: J = 2-6-2, K = 4-6-2, L = 2-8-2, M = 4-8-2, it appears that the determinant was a 2-wheel trailing truck.) but Pennsy always marched to their own drummer.  The PRR O-1 class was a not very successful 2-Bo-2 electric.  If there had been a steam 4-6-4 with a keystone number plate it would indeed have been a P-something (P-6 if built after the P-5 class electrics.)  As for 4-wheel trailing trucks, the letter system broke down when they were introduced on the (second) J, Q and T designated locos.

Logically (PRR skewed logic) a PRR 4-8-4 would have been a class R, between the 4-6-4 P and 6-8-6 S classes.  They could have done a lot worse than simply copying the N&W J - but then, Pennsy wouldn't have had ANY outside designs if the USRA hadn't forced them to take a couple!

Chuck

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Posted by JimValle on Tuesday, January 20, 2009 4:59 PM

Chuck's comment is interesting.  The Pennsy actually did "borrow" a N&W J class 4-8-4 for testing.  They liked it pretty well but were put off by the 70" drivers.  They wanted an engine that could maintain 100 plus MPH between Crestline and Chicago and believed that this mandated an 80" driver.  The N&W J could do 100 but that kind of speed would mean a lot more wear and tear on both the track and the engine than an 80" drivered engine would experience.  As for avoiding four wheeled trailing trucks, the Pennsy relied on the superior steaming qualities of its Belpiaire boilers which furnished more steam on less grate area than the more common radial types.  The Belpiaire boiler was the real secret of the K4's and M1's success as road engines. Anyway, a lot of folks have questioned the value of the 4-6-4 wheel arrangement.  Why invest in this type when for just a little more expense you could add one more diving axle and have a dual purpose Northern instead of this passenger traffic only race horse.

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Posted by locoi1sa on Tuesday, January 20, 2009 5:54 PM

 The PRR being practicle about its road engines did not like more non drivered wheels under locos. Front and rear trucks were put on for stability and high speed manuvers and took valuable weight from the drivers. Any thing rated for 50 mph and above got 4 wheel or 6 wheel lead trucks and trailing trucks and anything below fifty got a single axle lead truck. The M1 was a dual service loco got the 4 wheel lead truck. The I1, L1, and J1 were drag freights set for 35 mph got 2 wheel fronts. The C&O T1 which was copied by the pennsy got the 4 wheel trailing truck due to the booster whether they got them or were removed later. The J1 was copied so well when they first were built with a cast frame with a designe fault seen on the original C&O T1. Then came the J1a with steel fabricated frame. The book Black Gold Black Diamonds tells the story of the J.

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Posted by jeremygharrison on Wednesday, January 21, 2009 6:48 AM

tomikawaTT

<snip>  If there had been a steam 4-6-4 with a keystone number plate it would indeed have been a P-something (P-6 if built after the P-5 class electrics.)  As for 4-wheel trailing trucks, the letter system broke down when they were introduced on the (second) J, Q and T designated locos.

Logically (PRR skewed logic) a PRR 4-8-4 would have been a class R, between the 4-6-4 P and 6-8-6 S classes.  They could have done a lot worse than simply copying the N&W J - but then, Pennsy wouldn't have had ANY outside designs if the USRA hadn't forced them to take a couple!

Chuck



Was there not an R-1 4-8-4 (2-Do-2) electric?

What happened to classes P-1 to P-4? Were they still born projects, or what? (If the P-5's were indeed the first Pennsy 4-6-4's, why weren't they P-1?)

Given that (AIUI) the Pennsy owned the N&W, there seems to have remarkably little interchange of ideas between Roanoke and Altoona, when one might have expected many designs to have been common.

And, yes, the 'standard' name or the 4-6-4 wheel arrangement over here (England) is Baltic. 

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Posted by daveklepper on Thursday, January 22, 2009 1:32 PM

Both the PRR and the N&W were run by very independently mnded people, and the PRR saw the N&W as a cash cow and didn't want to interfere in a continual supply of new cash.

 

Yes. there was one electric R-1 4-8-4 ot 2-D-2 if you insist.   It was built at the same time as "Rivets", the original prototype GG-1, and compared with it.   It lasted until well after WW-II and was frequently seen on the Lehigh Valley Hunter Tower-Penn Station-Sunnyside moves, and also to Soth Amboy on the New York and Long Branch Jersey Shore trains.

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Posted by CSSHEGEWISCH on Friday, January 23, 2009 7:16 AM

The PRR R1 was built at the same time as the first GG1 as an alternate design for the replacement of the P5 in passenger service.  The R1 was originally numbered 4800 and the GG1 was 4899.  A series of tests was run in which the GG1 was deemed to be the better design and was selected as PRR's standard passenger electric locomotive.  The GG1 was renumbered to 4800 and the R1 was renumbered to 4899, and later to 4999.

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Posted by The Dude With The Hair on Friday, January 23, 2009 9:06 AM

 I wonder how much redesign work it would take to put 80 inch drivers on a N&W J class...and if you did, would it take too much away from that locomotives performance on grades...Just a random thought.

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Posted by feltonhill on Friday, January 23, 2009 3:56 PM

 ATSF 2900 class would be about the best approximation.  They have similar (but not identical) size boilers to a J, and 80" drivers.  A big problem is sufficient clearance between the drivers and the main boiler course at the combustion chamber.

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Posted by Stoop Davy Dave on Friday, January 23, 2009 5:20 PM

 "and why didn't they give a T-1 a name?  "

It's just as well I wasn't running the show. 

There's no way I could've resisted calling it the "Flash Gordon."

 

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Posted by CSSHEGEWISCH on Saturday, January 24, 2009 6:50 AM

Stoop Davy Dave

 "and why didn't they give a T-1 a name?  "

It's just as well I wasn't running the show. 

There's no way I could've resisted calling it the "Flash Gordon."

 

The first two T1's (6110 and 6111) were referred to by Altoona shop forces as "Buck Rogers" and "Flash Gordon".

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Posted by wjstix on Tuesday, January 27, 2009 12:36 PM

The Dude With The Hair

 I wonder how much redesign work it would take to put 80 inch drivers on a N&W J class...and if you did, would it take too much away from that locomotives performance on grades...Just a random thought.

It probably would be impossible, the drive wheels are probably only a few inches apart at the flanges / tires. I know some NYC 4-8-2's  were designed to have larger drivers added later, so their drivers had larger-than-normal spacing.

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Posted by The Dude With The Hair on Tuesday, January 27, 2009 11:05 PM

 I know it wouldn't be as simple as just slapping new drivers on it and being done with it. You'd have to at the very least make the engine longer and taller to fit the wheels under it. I just wondered because none of the other 4-8-4s (to my knowledge) had the same boiler pressure and such as the J-class, so I guess I wondered what you'd get if you slapped a J's boiler and cylinders on a bigger (though just as well balanced) set of drivers.

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