Pennsy T1

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Pennsy T1
Posted by Lithonia Operator on Tuesday, July 16, 2019 6:51 AM

I know virtually nothing about the state of railway preservation in the early 50s.

Still, I find it mind-boggling that not a single T1 was preserved, not even one for static display somewhere.

Was PRR perhaps at odds with the preservation community? Was there something political in this?

I find it odd that there was no group or individual that could pay PRR more than the scrap value of just one, and just store it until such time that money could be raised to at least spiff one up cosmetically.

Frankly, it seems like PRR would have outright donated at least one to a museum. (For Pete’s sake!)

It‘s such a tragedy none were saved. Unbelievable.

BTW, how many of you folks think that T1 group will successfully build a new one? Seems like pie in the sky to me ...

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Posted by Overmod on Tuesday, July 16, 2019 7:39 AM

We have threads discussing this.

I still find it incredible that an organization like the Railroadians weren't given the opportunity to purchase the S1 for the $35,000-odd that was the nominal scrap value, especially since there was so much internal support in the PRR organization to preserve the locomotive.  (Remember that PRR had expended crazy money on this locomotive, in part for reasons suspiciously similar to those that would be used in development of the BCR coal turbine).

The situation with the T1s was different.  In order to build the 'batch' PRR thought desirable when the order was placed, a very significant equipment trust obligation was incurred.  For one of the T1s to be preserved, the whole of its debt would have to be paid, likely at 100 cents on the dollar, and an attempt to ask the bankers about this might raise the spectre of having to pay off the trust early on all the other engines.  Meanwhile of course PRR had this enormous amount outstanding precisely at the time it wanted to obtain expensive first-generation diesels, often from builders who were unaccustomed or unable to provide GM-style financial assistance.  Personally, I don't find it surprising under these conditions that the locomotives became perceived as dogs, had their improvement program curtailed in 1948 just as fixes for the common issues were developed, couldn't find any homes on the secondary market for what PRR would have to charge for them (those of you who have had to sell a car still being 'paid for' may appreciate this a little more) -- and that an accelerated retirement and scrapping as 'utter failures' was an expedient way for everyone to get the trust requirement relieved early.

The point here is that only a railroad or a bank had the kind of money necessary to actually take title to a T1 under these conditions, and not unsurprisingly no one who could command that kind of money wanted to buy into a 'failure', no matter how cool the thing looked.

The T1 Trust has been at the 'takeoff point' for some time regarding actual construction of the locomotive -- significant parts of the job actually being done as far as proof of concept and recovery of the technological knowledge and skill needed for fabrication.  These and assembly of the necessary drawings are the major 'uncertainties' in the project ... and of course are all substantially complete.  The same is true for the testing and operational support necessary to maintain the 'asset' once it has been constructed, something most folks planning 'replicas' don't give much more than thought to.  Personally I don't think this will have to wait for the current shoestringing of financing and construction that puts operability as far out as 2030, but of course time will tell.

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Posted by Overmod on Tuesday, July 16, 2019 7:58 AM


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Posted by Paul Milenkovic on Tuesday, July 16, 2019 8:19 AM


The "financials" of the PRR are a refreshingly original insight into why the T1s were regarded as "failures."

The one quibble I would have with that is that the "successful" passenger steam engines of the late era -- Niagara and N&W J -- were not simply locomotives.  They were part of an overall system that maintained them.

Back on the Allegheny 2-6-6-6 thread, the glib response was offered that "steam was too expensive to maintain."  Well, there were instances where this was the case, just as there were instances of where improperly balanced steam engines were operated at speeds that kinked up miles of track.  But N&W steam operations were a sterling example where maintenance was considered part of the whole package of running steam economically and N&W had innovative locomotive design features and maintenance operations making their locomotives cost effective.  An effective maintenance operations was part of the New York Central getting high utilization out of their Niagaras although maybe cost-wise they weren't at the level of N&W who had developed it to an art?

The maintenance infrastructure (along with crew training and everything else) associated with the T1 appeared to be haphazard, and that ties into the theory regarding PRR being under financial strain.  If someone comes along and says, "my granddad worked in the PRR shops and who are you calling haphazard", I am not talking about the skill and dedication of PRR workers, I am talking about high-level management and planning.

But, there are some nagging details about the T1.  The Type A oscillating cam valve gear, I have read, took major disassembly of the locomotive to repair, especially the gear for the rear engine set.  If the "tweaks" to the T1 would have included replacing the gear on every engine with Type B rotary gear which was said to be much less problematic, then yes, I agree it was only the financials ruining the historical reputation of the locomotive.  Still, there were aspects of "detail design" that had problems.

If GM "killed the electric car", what am I doing standing next to an EV-1, a half a block from the WSOR tracks?
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Posted by Overmod on Tuesday, July 16, 2019 11:51 AM

There are a number of issues you bring up that are rich subjects for discussion.  I will give you my opinion on these based on the research that's been done so far.

PRR, although most definitely both 'privy to' and able to use without royalty the maintenance systems developed by N&W, kept their steam maintenance relatively slipshod, and this extended right through the 'leased' ATSF locomotives on ore runs in the mid-Fifties.  In an era where well-classified, washed, 2" gas coal was touted as an important part of true steam 'economy', PRR went more and more to what appeared to be mine-run lower-rank cheap stuff, and paid the cost for the low price.  We've already gone into the problems with training and maintenance for sophisticated equipment (there's a parallel for Baldwin diesel injectors and the like when those started to come on the property) and I have little doubt that this was responsible for quite a few T1 'problems', even before it started becoming expedient to have problems...

The type A gear was something of a scam to begin with, since poppets don't really behave the way long-lap long-travel piston valves do, and they don't respond proportionally to SHM valve-gear adjustment as well, even if the cams are ground to facilitate proper unshrouding at short cutoff.  (There are ways around this with some complex mechanism in the followers, but this wasn't tried on PRR and I am frankly glad.)

Now, remember for a moment that the type A gear involves two "boxes".  The first, which was where most of the maintenance trouble developed, was the little 'stunted Walschaerts' that took the derived drive from the crossheads and performed the 'cutoff' adjustment.  The second, which is the awful thing upended and stuck in front of the T1 rear engine in an inaccessible state, was the 'nightmare box' that derived the actual motion to be imparted to the valve stems (the valves being closed not desmodromically, but purely by springs as in an automobile engine -- this being one of the great Things Having To Be Changed to keep the engines running with minimal valve bounce and fracture ... but we've discussed that already).  Supposedly the actual cambox was sealed, didn't really leak all that much, and had very little wear in normal service... I suspect much the opposite might have been true when a valve broke or seized or locked in service, but no one seems to have documented this (certainly no one from Franklin is likely to have!)

The RC that was installed on 5500 is interesting because it was bridged to use the type A valve arrangement (as seen on the Franklin company 'shield') with a rotary-cam setup -- that is why it is called type "B-2".  In my opinion it would have been relatively easy to install on more of the production T1s, certainly at less cost than the heroic "T1a" cylinder modifications.  As an aside, the job required to adapt actual Franklin contemporary type B (or "C") would have involved very similar 'surgery' to the cylinder castings, with the added joy of more Franklin proprietary valves and mechanism as seen on ATSF 3752 and discussed by Vernon Smith.

The immediate issue that I'd be asking is whether Franklin would waive royalties on the RC conversion parts and spares since the type A had proven problematic.  The second issue would be to look carefully at whether the type B-2 solved any of the problems with facilitated high-speed slipping that the OC gear had, most particularly the "140mph" slipping that contemporary engineers claim to have observed (probably from devices recording driver rotational speed, and obviously not from either the Jones-Motrola speedometer, which only went to 100, or from handheld timing of mileposts).  We can then get into all the fun involved with spherical followers on a hardened variable cam when (1) there may be valve bounce and shock reflected back into the follower contact, and (2) parts of the cutoff profile see much more frequent and rapid use than others.  Problems with this in immediate postwar British practice I expect; for it to affect American practice indicates there were problems indeed with the state-of-the-art metallurgy, at least at any cost-effective price point.  Certainly by type D Franklin, like the Brits, had moved to line-contact stepped cams and all the problems those impose on performance, and while of course 'economy' was a distinctly secondary design concern on the Vulcan 2-8-0 conversions, you see some care in the patent application to note how what is basically fancy wiredrawing produces water-rate economies in "automatic" operation... now tell me how well this would work on a T1 fired in anger.

I don't think you can attribute much of the PRR troubles to 'financial strain' as much as to somewhat inadequate, and certainly poorly-prioritizing, leadership.  Beyond that I don't care to go, as most of the principals are dead and couldn't either explain or defend themselves.  Much of what was done appears 'penny wise and pound foolish' in ways that can't really be justified expediently by lowest daily expense, and in a sense PRR lacked the steam requirement and volume that justified NYC's and N&W's different approaches to systematic maintenance for high spot availability.  (It is difficult for me to imagine folks at Shaffer's Crossing in air-conditioned asbestos-lined reflective suits climbing in and out of fireboxes on engines in steam with small hammers, for example.)

Thing is that NYC Niagaras, with all their optimized maintenance and well-implemented design, were gone not a half-decade after the T1s.  Which to me says much more about the dying-off of excuses for high-speed steam locomotives than anything about turning them quickly or utilizing them for longer nonstop running.

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