slippery T-1

[Convicted One]

I was checking out this video of the old Pennsey T-1s in action, and was taken by surprise the way the front drive wheel set just breaks loose while the rear set maintains traction

Look at around 2:56 in the timeline.

[selector]

The T1 wasn't any more slippery than any other steamer whose throttle was cracked open too much by the hogger.  Yes, it was observed that the front engine spun more often than the rear, so there may be "something" to it, but the better engineers didn't seem to think the engine was any worse than any other.  It just took a knowing and deft hand.

There are several threads dealing with tractive efforts.  Here is one that may interest you.

http://cs.trains.com/forums/379603/ShowPost.aspx

Cheers.

-Crandell

[Convicted One]

Thanks, the discussion your link to is certainly interesting.

I've often read that a point of dissatisfaction with the T-1 s was that they had poor traction, And I'd never really understood "how" their traction was a problem.

Seeing on this video, with one set of drivers speeding while the other set remained in traction, gives me perspective on what the other complaints might be based on

i wonder if the engineer had seperate controls for the one set of drivers, versus the other, or if they shared a common throttle?

[selector]

Yes, on one of the sites I have been to (fallenflags, or maybe the PRR Historical Society's own archives...can't recall) they have an image of the backhead of a T1, and it clearly shows two separate throttles.  I don't know enough to say with confidence that every locomotive with two or more engines under it had a throttle dedicated to each engine, but it certainly wouldn't surprise me to learn that most did.  Maybe an expert will pipe up.

-Crandell

[feltonhill]

First - Watch more than one T1 video.  There are more out there than the one you refer to.  One shows a T1 climbing the approach to the Miss. River bridge out of St Louis, sand flying and never missing a beat. Another shows the one engine slipping while the other doesn't, with the sand dust indicating only one engine has working sanders. Guess which one. 

Second - Watch the video of UP 3985 on Clinchfield.  First the front engine slips then the rear, almost at stall speed on a very difficult S-curve.  So its not unusual for one engine of a 4-cylinder simple loco to slip while the other doesn't.   Joint control over two independent engine sets adds an extra challenge (pun intended) for the engineer.

Can't be more specific about the video titles because I'm on the road.  Can check my library when I get home.

 The T1 had one throttle, front end like most modern steam locos, not two.  Where did you see the backhead photo?  There are several cab photos available in books.  I may have the one you saw and can possibly identify the second lever you're referring to.

Thanks for the reference to the 2005 thread.  Both Old Timer and I tried to put our best info into that discussion. I've kept digging into the T1's performance in the ensuing 3 years,and am in no mood to retract a word of what I wrote in 2005. 

[selector]

It looks like you are quite right, feltonhill.  Here is the link http://crestlineprr.com/t1backhead.html

What I thought I recalled from my rather poor memory was that nearly identical device to the right of the throttle, further forward, right of the dial.  I could visualize that, not having seen the photo for many months, and felt I had seen two.  Nope, just the one as you have said.

Thanks for piping up...I felt confident we'd hear from you.

-Crandell

[Convicted One]

First - Watch more than one T1 video.  There are more out there than the one you refer to.  One shows a T1 climbing the approach to the Miss. River bridge out of St Louis, sand flying and never missing a beat. Another shows the one engine slipping while the other doesn't, with the sand dust indicating only one engine has working sanders. Guess which one. 

 

 

The additional insight you offer is appreciated.  Do you have any  links to color photos or videos of the T-1?

I was really surprised to see an animated T-1 in the  2004 children's movie "Lemony Snicket's Series of unfortunate events"  (look towards the very end of the  video)

[wjstix]

Ya that wasn't that uncommon. I've seen video of UP challengers doing the same thing (in a WB Video production IIRC).

I don't know if it would be less common (or impossible?) with a true Mallet, where the exhaust from one set of cylinders is sent to power the other set of cylinders??

[J. Edgar]

ive read quite a few first person stories from old  imers....and the suggestion ive gotten is the T-1 was indeed "slippery" when starting....as far as 1 engine slipping more i would assume the front engine slips more account slightly less weight....the firebox with double sheets, water, and tons of coal must weigh much more then the smokebox with just smoke in it...and most if not all the motion pictures ive seen of "dual-engined" steam locomotives the front always seems to slip more then the rear

[tomikawaTT]

Bill Withuhn published the opinion that the T-1 would have been a much better locomotive if the two separate sets of drivers had been linked together (by rodding or gearing.)  Not only would the two-axle slip have been tamed, but dynamic augment would have been eliminated by rigging the rod timing so the pistons would have been traveling in opposite directions.  Unfortunately, it didn't happen.

Not only could Mallets slip, they tended to have the driver sets slip alternately.  If one engine slipped, that would upset the steam pressure balance and cause the OTHER engine to start slipping while simultaneously reducing the first engine's available power and allowing it to regain its grip.  The final development of the N&W Y-6b was the lead(Pb)-loading of the front engine to curb its tendency to slip.

Chuck

[KCSfan]

I'd just like to ditto what both Selector and Feltonhill have previously stated about the myth that the T-1's were slippery. The following is a quote from a reply I posted some time ago on another forum.

"While I have no first hand knowledge of the T-1, I have had Pennsy enginemen tell me they were "slippery". Any engine will slip if the tractive effort generated at the cylinders exceeds the frictional force" (adhesion) "between the drivers and rail. What I think they meant was the T-1's were more prone to slip than the K-4 Pacifics they were used to running. This translates into the T-1's having a more critical relationship" (than the K-4's) "between the weight on their drivers and the power generated at their cylinders."

The problem was that many enginemen operated the T-1's the way they had the K-4's they were used to running. You could no more do this than you could run a 4-8-4 the same way you would run a 4-4-0. The T-1's could walk away with 25 heavyweight cars without a slip if the engineman used sand and a "light" hand on the throttle until the train got up to about 20 mph. 

The problem was compounded if a T-1 was sent out with one of its two sets of sanders not working properly. Feltonhill alludes to this in referring to the video of the T-1 leaving St. Louis with one set of drivers slipping due to no sand.

Mark

 

 

 

[Convicted One]

just for kicks, I found a couple color photos of the T-1, and thought I'd share

 

http://img228.imageshack.us/img228/3282/t12bqt2.jpg

http://img117.imageshack.us/img117/2014/t1biggbccvy6.jpg

[selector]

There are also some nice images at http://www.rr-fallenflags.org/prr/prr-loco.html

Scroll down to the type and find several images.  Also, images of its cousins, the Q's.

My favourite image, if it is a proper link, is the follwing: http://www.fortunecity.com/meltingpot/finland/1060/t_6110.html

 

[Convicted One]

All good photos, but the last one you list IS very good,.  thanks.

Hate to seem like a giddy nostalgist, but it truly is a shame that not even one of those old beauts  found a safe home, for posterity.But then again I recognize the economics at the moment had to be a driving factor.

Just out of curiousity, I wonder just how much $$  the RR would realize  from a scrapper for such a loco? are we talking about tens of thousands, typically, or much more?

[selector]

I would guess that, at the time, it would be more like hundreds of dollars....like 2-3 hundred dollars.  There was no incentive for recycling like there is today, so no grants or government inducements to recycle materials...it was strictly business, and the business had to pay workers enough to keep them somewhat loyal to the enterprise, plus the owner wanted something.  I would guess, then, that there wasn't a lot to show for the scrapping from the Pennsy/Penn Central's balance book point of view, except that as a flagging corporation it needed everything, even hundreds of dollars.

It would take three or four men working 8 hours each about two to three weeks to break up a tender and engine...or something of that order?  If they earned $3/hr in 1955/56 (I'm just guessing) you can understand how iffy the margins are going to be...it's a wonder the Penn Central didn't pay to have them scrapped instead of receiving scrap value.

This is all just my attempt at ball-parking.  Maybe I should be over at the next field?

[DSO17]

     It seems to me that back in the 1960s steam locomotives had a scrap value in the several thousand dollar range, maybe $4000 - $8000 or so. I don't think it would take more than a couple days for a few men to cut one up with large torches. Back then nobody would have worried about lead paint, asbestos, etc. Just my impression from way back when - don't have any numbers to back it up. Kind of a depressing topic.

[Texas Zepher]

Reading with interest. Know nothing about the T-1 but what I've read here, let me guess, the T-1 had rollerbearings on both the axles and the driving rods?

[feltonhill]

The T1s had roller bearing everything - rods, drivers, lead and trailer truck, tender trucks.  During the Altoona tests, their machinery efficiency was very high (can't find the exact number right now) which indicated low internal resistance.

There have been many articles in the PRRT&HS magazine, The Keystone, the N&WHS magazine, The Arrow, and C&OHS magazine, C&O History, in the past five years or so covering all aspects of the T1 both on PRR and tests conducted on C&O (1946) and N&W (1948).  Back issues are available separately from COHS and PRRT&HS, but not NWHS at this point.

The text of the C&OHS article can be found at 

findarticles.com 

but lack of photos and graphics make it harder to understand.  Nonetheless, it's a free site, and will give you an idea of the information and level of detail you can find on theses locos.

[Texas Zepher]

The T1s had roller bearing everything - rods, drivers, lead and trailer truck, tender trucks.

I figured as much.  The NP Z-6s were purchased 1/2 with friction bearings and 1/2 with roller bearing everything.....   The second half were slippery locomotives. However slippery and all, they were so much more efficient that the NP sent the first set back to be refitted.

[timz]

The T1s had roller bearing everything - rods, drivers, lead and trailer truck, tender trucks.

The NP Z-6s were purchased 1/2 with friction bearings and 1/2 with roller bearing everything...

Like he said, "roller bearing everything" would include the rods.

[feltonhill]

And no 4-6-6-4 had roller bearing rods (along with everything else).  The last five N&W Class A's were unique in that position, as far as articulated freight power was concerned. 

It seems that if PRR could have put roller bearings on the bell, whistle and headlight of the T1, they would have done so!!!