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WP & D&H 4-6-6-4 steam locomotives

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WP & D&H 4-6-6-4 steam locomotives
Posted by IA and eastern on Wednesday, August 3, 2022 6:00 PM

Some people claim that were faults with the WP & D&H 4-6-6-4 steam locomotives. What was wrong with these locomotives? Gary

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Posted by Backshop on Wednesday, August 3, 2022 6:10 PM

What faults have you read about.  We can't (maybe) correct them if we don't know what some think they are.

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Posted by Flintlock76 on Wednesday, August 3, 2022 8:26 PM

I don't know anything about the WP's Challengers, but the only negative thing I've ever read about the D&H's Challengers was the spindly-looking pilots (cowcatchers) the locomotives were equipped with.  They just didn't match the brawny good looks of those 4-6-6-4's.  Aside from that as far as I know the D&H was perfectly satisfied with them, with no complaints.

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Posted by kgbw49 on Wednesday, August 3, 2022 10:13 PM

Interesting.

D&H had repeat orders up to forty.

https://www.railpictures.net/photo/58968/

WP had a single order of seven.

https://digital.denverlibrary.org/digital/collection/p15330coll22/id/44200

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Posted by Overmod on Thursday, August 4, 2022 8:29 AM

Frankly, without knowing who the "some people" are or were, and in what media they said or published it so we have some idea of where to look for something objective, the original post appears little better than trolling.

The only problem I remember with the D&H Challengers -- aside from the 'issues' common to Challengers in general -- had to do with the patent arrangement used to hold the valve-gear eccentric crank in place.  I can't get at the patent information now, but as I recall the 'object of the exercise' was to have a very lightweight crank, to reduce the need for overbalance especially in the forward engine, while maintaining very firm clamping, beyond what a typical bolted and keyed arrangement would provide.  The clamping was outboard, easily inspected and as easily adjusted when necessary.  However, I don't see it used on other, later projects that would surely have benefited, the 1948 second rebuilding of the (utterly awesome) C7NW H locomotives being one example.

If I recall correctly, the WP Challengers were WPB wartime power.  Unsurprisingly they didn't last very long once road-diesel order books were open again... it probably wouldn't have mattered no matter how free of mechanical faults they might have been.

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Posted by kgbw49 on Saturday, August 6, 2022 9:10 PM

Minor addition of data:

steamlocomotive.com lists the build year as 1938 for the seven Western Pacific Challengers

https://www.steamlocomotive.com/locobase.php?country=USA&wheel=4-6-6-4&railroad=wp#343

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Posted by Leo_Ames on Saturday, August 6, 2022 11:28 PM

Yeah, the Challengers were pre-war construction.

I've read that they considered 4-8-8-4's (Not Big Boys but rather an enlarged take on their successful 2-8-8-2's) until they experienced FT demostrators. They quickly ended future steam plans.

I assume those SP designed 4-8-4's late in the war only were accepted due to limits on FT production and wanting more power online asap for the invasion of Japan that thankfully never happened. I assume they were built for SP by Lima but got redirected by the WPB (Much like the six UP Challengers that ended up on the Rio Grande instead).

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Posted by kgbw49 on Sunday, August 7, 2022 8:43 AM

Yes, the 4-8-4s were SP GS-6 identical to SP 4460-4469.

WP added elephant ears after the fact to give them a more distinctive look from the SP GS-6, but they were GS-6 down to the 73 1/2 inch drivers.

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Posted by kgbw49 on Sunday, August 7, 2022 9:09 AM

And the WP 4-8-4s also had the SP skyline casing in addition to the elephant ears.

https://www.steamlocomotive.com/whyte/4-8-4/USA/photos/wp482-hechtkoff.jpg 

 

 

 

 

 

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Posted by BEAUSABRE on Sunday, August 7, 2022 9:57 AM

WP thought enough of them to send one to the 1948 Chicago Railroad Fair. Their operating territory was the isolated desert between Elko, NV and Salt Lake City, UT so they never got the railfan attention they perhaps deserved. 

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Posted by Erik_Mag on Sunday, August 7, 2022 1:24 PM

Leo_Ames

I assume those SP designed 4-8-4's late in the war only were accepted due to limits on FT production and wanting more power online asap for the invasion of Japan that thankfully never happened. I assume they were built for SP by Lima but got redirected by the WPB (Much like the six UP Challengers that ended up on the Rio Grande instead).

It's possible that the WP GS-6's were redirected SP orders, but I suspect that the WPB told Lima and WP to build the WP order to the Espee design to eliminate the extra manpower needed to produce a WP specific locomotive.

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Posted by BEAUSABRE on Sunday, August 7, 2022 2:01 PM

From an earlier posting on another thread. "The WPB also decreed that 1) only established designs could be built 2) due to the time it took to set up and tear down jigs and fixtures, no small orders would be accepted. WP wanted six Northerns, so it had to accept its order being tacked on to a SP one. "Piggy-backing on the first of two Southern Pacific orders for its GS-6s was the Western Pacific, which took delivery of this sextet in 1943. The unit price was $206,655.""

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Posted by kgbw49 on Sunday, August 7, 2022 3:22 PM

BEAUSABRE, I always thought the WP Challengers had a little bit of the UP CSA-1 and CSA-2 Challenger in them, with the headlight on the pilot for WP instead of on the boiler for UP.

The ALCo boys upped the driver diameter 1" for WP and increased the boiler pressure 10 lbs and squeezed another ton or so of tractive effort out of the WP machines.

I would think the WP Challengers did not take a back seat to any other railroad's Challengers. The fact that they lasted until the end of steam on the WP while operating in the middle of the desert certainly has to say something about what WP thought of them. If for some reason steam had lasted on the WP later into the 1950s I am sure that the WP Challengers would have been in the mix right to the end.

Here is a CSA-2 for comparision with the WP M-100 above.

https://digital.denverlibrary.org/digital/collection/p15330coll22/id/56628

And another link to a picture of M-100 402 on a similar angle to the CSA-2.

https://www.wplives.com/archives/steam/4664/402.php

By the way, wplives.com has a great archive of WP steam of all classes. WP had some fine-looking examples of modern steam-powered locomotion.

 

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Posted by Leo_Ames on Sunday, August 7, 2022 3:59 PM

BEAUSABRE
From an earlier posting on another thread. "The WPB also decreed that 1) only established designs could be built 2) due to the time it took to set up and tear down jigs and fixtures, no small orders would be accepted. WP wanted six Northerns, so it had to accept its order being tacked on to a SP one. "Piggy-backing on the first of two Southern Pacific orders for its GS-6s was the Western Pacific, which took delivery of this sextet in 1943. The unit price was $206,655.""

I just pulled out Kalmbach's special issue dedicated to 4-8-4's that they published a decade ago. The story in it about Lima's various 4-8-4's from author Neil Carlson contradicts that.

That story says that Southern Pacific ordered 16 GS-6's in 1943, anticipating traffic increases as the war's focus shifted to the Pacific. These were essentially copies of the GS-2's with 73 1/2" drivers due to SP believing that the War Production Board wouldn't approve 80" drivered passenger engines.

But Southern Pacific didn't receive all 16 locomotives, with 6 redirected by the War Production Board to the Western Pacific that was also anticipating a traffic surge.

However, the story does say that the 8 Central of Georgia GS-6's were tacked on to the order by the War Production Board in lieu of requested Baldwin 4-8-4's, rather than being diverted from production intended for Southern Pacific. One of the few steam classes designed for oil-firing but converted to burn coal. They also lacked the skyline casing, booster engine, the conical nose, and had relatively small tenders due to turntable limitations.

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Posted by kgbw49 on Sunday, August 7, 2022 5:16 PM

Leo_Ames, thank you for that reminder of the C of G GS-6 locomotives. C of G got the biggest apple that could fit on the railroad!

Interesting how that GS-6 design, which was basically the GS-2 design without any skirting, turned into a "boomer" locomotive design!

WP also had a handful of ex-FEC 4-8-2 Mountains on the roster - finally working in territory that had actual mountains after all those years on what might have been (and might still be) the most water-level of all water-level routes.

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Posted by Pneudyne on Tuesday, August 9, 2022 2:47 AM

The D&H J-95 class 4-6-6-4 looks to have been a “refined” version of the original UP design.  Most of the basic dimensions were the same.  It had cast frames and a single-plane articulated joint (*), whereas the UP original had bar frames and a modified two-plane articulated joint, the modification being the addition of a friction damping mechanism for the pitch axis.  Nominal axle loading was higher, at 68 000 lb as compared with 65 000 lb.  And the front driver set had a slightly greater static loading than the rear set, to offset weight transfer on upgrades.  The front engine steam pipes conformed to the later Alco jack-knife-with-ball joints pattern.  (Perhaps the J-95 was the first application?

 

The higher steam pressure, 285 lbf/in² as compared with 255 lbf/in², did not fully offset the reduced cylinder diameter, 20.5 in as compared with 22 in.  (The net tractive effort ratio was 0.97.)  Given that the J-95 had a higher adhesive weight (406 500 lb) than the UP CSA-1 (386 000 lb), it looks as if D&H was concerned about the apparent potential slipperiness of 4-6-6-4 locomotives.  (Although a factor of adhesion of 4 was probably fine for x-8-8-y articulateds, something higher, maybe towards 4.5, was evidently preferable for the x-6-6-y type.)

 

The single-plane articulation joint necessitated that the front engine be equalized as a single unit, rather than in two sections, but otherwise the springing was similar, as were the lateral controls, which were one lateral motion device per engine unit short of the “full works” Alco/Blunt lever system.  (Maybe the later D&H builds were “full works”, as that was used on the 1943 D&H K-62 4-8-4.)

 

Both the “Railway Age” 1940 August 10 and :Railway Mechanical Engineer” 1940 September articles on the J-95 note that the crossheads were of the Laird types, arranged with the Becker design of wrist pin, removable from the outside.  The Becker device was covered in US patent 1599740 of 1926 September 14, filed 1924 September 30.

 

The WP M-100 class 4-6-6-4 might have been simply a somewhat heavier version of the UP CSA-1, although I haven’t seen a detailed technical treatment of it in the literature.  Adhesive weight was 416 000 lb, for an average axle loading of 69 500 lb.  The 265 lbf/in² boiler pressure slightly more than offset the 70 inch drivers, the net tractive effort ratio as compared with the CSA-1 being 1.02, against an adhesive weight ratio of 1.08.

 

Regarding the WP’s stillborn interest in 4-8-8-4 locomotives, there seem to be two versions of this story.  Virgil Staff, in his book “D-Day on the Western Pacific”, notes that in 1941 February the purchase of 10 such locomotives was contemplated for service over Wendover Hill, displacing the M-100 class 4-6-6-4s from that section.  It was said “Contacts were immediately made with the Union Pacific, and WP considered having its own order attached to that of the UP power then under construction.”  However, the WP had second thoughts, and instead opted for the EMD FT.  The book chapter in which this was recorded was “Knuckle Busters or Big Boys!”.  A WP variant might have been slightly heavier, as WP appeared to work to a 69 000 lb nominal axle loading, as compared with 67 500 lb for the UP.

 

Staff appears to have been quite meticulous with his research for the book, so what he said is more likely to have been gleaned from the WP records than inferred by him from less definite information.  But that said, it is possible that both stories are applicable.  As well as considering the UP design, WP might also have had a dialogue with Baldwin about a 4-8-8-4 derivative of its M-137-151 class 2-8-8-2.  (The DM&IR 2-8-8-4 of 1941 was also said to have been a derivative of the WP locomotive.)

 

 

(*)        The J-95 was, as far as I know, Alco’s first application of the single-plane articulated joint.  N&W had used it in 1936, on it’s a class 2-6-6-4.  After Alco, Lima used it on the 1941 C&O 2-6-6-6.  Baldwin was late though, with first use on the B&O EM-1 class 2-8-8-4 of 1944.  But then, somewhat surprisingly, it also used it on the final batch (1949?) of the C&O 2-6-6-2 Mallet, in conjunction with bar frames.  I recall seeing that type of locomotive at the Baltimore museum (in the late 1980s I think), and being very surprised when I had a close look at the running gear.

 

 

Cheers,

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Posted by Leo_Ames on Tuesday, August 9, 2022 4:21 AM

In wondering where I had read that about WP's interest in 4-8-8-4's, I looked around a few books on my shelf and then got on the internet.

This might be my source.

"Further indications of the impending demise of steam came when WP was in the market for new power, and considered ordering ten new 4-8-8-4 locomotives similar in design to its highly successful 251 class. Top management also evaluated data received from its extensive testing with Electro Motive FT’s GM103 and Santa Fe Nos. 101 and 103. The decision was made in favor of the diesel. Western Pacific would never see another new steam locomotive."

https://www.wplives.com/about-wp/motivepower/steam.php

Not only is there not much detail (although it implies that they'd of been an enlarged version of their successful 2-8-8-2's), but it's obviously not even correct.

Western Pacific ordered FT's of their own in 1941 after the tests referenced in that quote had happened and the six 4-8-4's showed up in 1943. So WP certainly would see another new steam locomotive after FT demonstrators had shown what they could do on the WP.

I'd stick with what Virgil Staff wrote.

 

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