PRR T1 #5550 might be rebuilt from scratch!

I don't mean to get off topic, but watching that video..............jesus!!! For that engine, what a catastrophe!!!!!
 
I'll say that in any circumstacums, anything is possible. it be nice to see a t1 replica as well alongside with the NYC Hudson replica as well.

I wonder, why didn't the Pennsylvania railroad rebuild their t1s into streamlined 4-8-4s instead? it would be awesome.

Smash, from what I saw, that looks excessive. :eek:
 
I'll say that in any circumstacums, anything is possible. it be nice to see a t1 replica as well alongside with the NYC Hudson replica as well.

I wonder, why didn't the Pennsylvania railroad rebuild their t1s into streamlined 4-8-4s instead? it would be awesome.

Smash, from what I saw, that looks excessive. :eek:

Because the cylinders were cast integrally with the frame, and you just cant torch through that much metal, let alone bandsaw it. Also, you would need a larger pair of front cylinders, which once again, leads to an all-new frame. Expensive part to try, not to mention long time in the shop, when dieselization was pretty much decided.
CI-14467123230250091.jpg


Further, it would look pretty darn awkward trying to space the wheels out to take up the full frame to reduce pitching, but that would lead to longer heavier side rods and main rods, exactly what the PRR was trying to reduce. So therefore, a waste to convert to 4-8-4.
 
Because the cylinders were cast integrally with the frame, and you just cant torch through that much metal, let alone bandsaw it. Also, you would need a larger pair of front cylinders, which once again, leads to an all-new frame. Expensive part to try, not to mention long time in the shop, when dieselization was pretty much decided.
CI-14467123230250091.jpg


Further, it would look pretty darn awkward trying to space the wheels out to take up the full frame to reduce pitching, but that would lead to longer heavier side rods and main rods, exactly what the PRR was trying to reduce. So therefore, a waste to convert to 4-8-4.

They could've made the rods lightweighted, like the N&W j class, and the streamlined 4-8-4s in Australia look like the t1s, so think about it, imagine those two merged with the t1, and you got yourselves a pennsy lightweighted 4-8-4.

so there you go. hope this is understandable.
 
They could've made the rods lightweighted, like the N&W j class, and the streamlined 4-8-4s in Australia look like the t1s, so think about it, imagine those two merged with the t1, and you got yourselves a pennsy lightweighted 4-8-4.

so there you go. hope this is understandable.

1) What makes you think they didn't use lightweight rods in the first place?
2) The engine you refer to, the SAR 520, is altogether much smaller and sincerely incapable of performing the feats of magic the T1 was reputed of doing.
Consider driver diameter, tractive effort, general boiler areas, etc.

The N&W J was recorded at 111mph, and the UP FEF and NYC S1a were designed for and sustained 100mph. There are, however, unsubstantiated reports of 140mph in a T1. The SAR 520 only ever pegged 78mph with a design speed of 70.
 
1 or 2 T1's where equipped with boosters which helped eliminate low speed wheel slip and allowed for longer/heavier trains that they didn't normally run. (Note that the C&O should have tested these)

None the less crews with experience with the locomotive would not have problems with it and that's why it has a bad reputation, it's only as good as the crew operating it. But once it got through those growing pains there was really nothing wrong with them in their day-to-day operation. Also as previously stated, wheel slip indicators will help make it less of major issue early on.
 
The dream's not dead yet. Found this on the Facebook page "AltoonaWorks".

"June 24 at 7:30 PM, the T1 Trust will be making a presentation via teleconference to those in attendance at the NRHS Horseshoe Curve Chapter meeting. The event will be hosted by the Railroaders Memorial Museum in Altoona in their 3rd floor
lecture room. Attendance is open to the public. The T1 Trust's goal is to build a brand new PRR T1, the 5550. To learn more, visit their web sitehttp://prrt1steamlocomotivetrust.org/

Please note, the T1 trust is completely separate and independent of the NRHS, Altoona Railroaders Memorial Museum, PRR Technical & Historical Society, and of course, AltoonaWorks.info.
"

It would be amazing to see a real T1 running again, let alone even being built. It still doesn't seem very feasible though.
 
When UK enthusiasts resurrected the unique 'Duke of Gloucester' BR Pacific, they found several flaws in the original design and construction. These were corrected in the refurbishment, with the result that a locomotive that was originally an unreliable steamer, disliked by crews, is now one of the most popular and powerful locos in preservation, seeing much mainline use. It seems very likely that a 21st Century T-1 would include similar improvements that would solve the original's problems, and wouldn't it be a wonderful thing to see?
 
I just figured something out you guys!:eek:


If they had made the boilers more heavier, then the weight itself would help the drivers grip the rails more easily and would help the engine move more easily as so.:p


I think that's why.
 
I meant NOT TOO heavy to damage the tracks, but just heavy enough so that the drivers can grip is all. :p
That could have helped, though I suppose it may cause some restrictions.
If anything, I'd just fit them with enlarged sandboxes and have only specially trained crews work them.
 
That could have helped, though I suppose it may cause some restrictions.
If anything, I'd just fit them with enlarged sandboxes and have only specially trained crews work them.

That could work. It can make the T1s more able to pick up speed.


I mean, if we can make a replica of a T1, then we ourselves can make a J1 as well.


Think about it, one of the 16 wheeled tenders survives, so it saves us the trouble of needing to build the tender as so. All we need to do is build a replica of the engine itself, restore the tender to good as new, hook them up, and VOLIA, a operating replica of a PRR J1. :D


What do you think? :p


Is it wrong of me to assume that you're talking about weight restrictions?
 
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What do you think? :p


Is it wrong of me to assume that you're talking about weight restrictions?
Weight restrictions were exactly what I was referring to. Although, a T1 would be restricted even further as a result of its rigid chassis. Lines with sharper curves are out of the question, so there are probably not many routes it would be able to run outside of the former PRR main lines they ran on.

The tender is only a small fraction of the work that would be needed to be done. But yes, we certainly have the ability to build a T1 replica. The main issue would be if it were financially possible. Not only to build; but to run, maintain, and insure as well. It would be an incredibly expensive venture.
 
You wouldn't have to add more weight, just remove wheels. Too much of the T1's weight was on the pilot and trailing truck. 25% of the weight was on each set of drivers, this meant that the TF was low. Adding more weight to the locomotive wouldn't do any thing as the weight is still on 4 set of wheels.

Picture this, remember when you where younger and you still had training wheels on your bike? And youd hit a patch of sand. No matter how much weight or jumping up and down you did, the tire still spun because the training wheels where holding you up. T1 had the same problem.

If they had built it as a 0-4-4-0, it would have been fine, or even a 2-4-4-2. This would have put more weight on the drivers and thus boosted the TF. But they didn't. And adding weight would be BAD. Yes, bad. How so? There comes a point with any thing that if you add more weight, you need more power to move it. If they made the locomotive heavier, it would have to work harder just to move it's self. Make it heavy enough and it wouldn't have enough power to move it's self.

Think of it as a shopping cart. It rolls nice and easy. But as you add stuff too it it gets harder and harder to push. Until you cant even get it to roll down hill. (Yes, mass can induce enough friction on the wheels bearings to prevent them from moving.)
 
You wouldn't have to add more weight, just remove wheels. Too much of the T1's weight was on the pilot and trailing truck. 25% of the weight was on each set of drivers, this meant that the TF was low. Adding more weight to the locomotive wouldn't do any thing as the weight is still on 4 set of wheels.

Picture this, remember when you where younger and you still had training wheels on your bike? And youd hit a patch of sand. No matter how much weight or jumping up and down you did, the tire still spun because the training wheels where holding you up. T1 had the same problem.

If they had built it as a 0-4-4-0, it would have been fine, or even a 2-4-4-2. This would have put more weight on the drivers and thus boosted the TF. But they didn't. And adding weight would be BAD. Yes, bad. How so? There comes a point with any thing that if you add more weight, you need more power to move it. If they made the locomotive heavier, it would have to work harder just to move it's self. Make it heavy enough and it wouldn't have enough power to move it's self.

Think of it as a shopping cart. It rolls nice and easy. But as you add stuff too it it gets harder and harder to push. Until you cant even get it to roll down hill. (Yes, mass can induce enough friction on the wheels bearings to prevent them from moving.)
Adding weight is a bad idea, just as is reducing weight. Look at the goals we want to accomplish: do we want total perfect replica, or a good operational locomotive that looks like a T1? IMO, just modify the springing and related rigging, that transfers more weight to the drivers and reduce boiler pressure. Hence, reduced TE with higher axle loading kills the slipping mostly and minimizes the required re-engineering.
 
Adding weight is a bad idea, just as is reducing weight. Look at the goals we want to accomplish: do we want total perfect replica, or a good operational locomotive that looks like a T1? IMO, just modify the springing and related rigging, that transfers more weight to the drivers and reduce boiler pressure. Hence, reduced TE with higher axle loading kills the slipping mostly and minimizes the required re-engineering.


But reduced TE is what the key problem with the T1's was. the weight was spread over too many wheels. Yes re-rigging the suspension would help. I would like to point out that I never said making it heavier would help, in fact, quite the opposite. As I said, weight was not the problem but how it was placed on the rails.

And remember, you want HIGH TE. TE means Tractive Effort after all. Lets break it down a bit and see why high TE is good and low TE is bad. Lets say we have a locomotive that weighs 1000 pounds. It has 4 wheels meaning that 250 lbs of weight is on each wheels. Add more wheels, lets say the locomotive has 8 wheels, but still is only 1000 lbs. Now we only have 125 lbs per wheel. That's less then what most people weigh. That means if you put a motor with 1000 HP on that, very little of the power is going to the rails to move the locomotive. Your chances of slipping will increase.

Now for steam locomotives, things get tricky. Like math tricky.

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  • t is tractive effort
  • c is a constant representing losses in pressure and friction; normally 0.85 is used
  • P is the boiler pressure
  • d is the piston diameter
  • s is the piston stroke
  • D is the wheel diameter


So lets build a simple steam locomotive, a 0-4-0. Lets say it has 24 in drivers, weights 3000 lbs, runs at 150 psi, has 7in pistons and 1 foot (12in) stroke

So we get 0.85x150x7^2x12/24=3125.75

SO we have a good TE, but because our locomotive only weighs 4000 lbs, once we start generating full power, and get our TE up above 3000 our wheels will start to slip. If we try to move a car weighing more then our locomotive, wheels will slip.

Lets fatten up our 0-4-0 to say, 9000 lbs. Now we have 2250 lbs of locomotive per wheel, and 3125.75lbs of TE. We can now move a little train, but are slightly underpowered.

Lets make our 0-4-0 a 2-4-0. That's 1500 lbs per wheel, and only 6000 lbs of weight on our drivers.

Lets boots the boiler PSI on our 2-4-0 to 250psi

0.85x250x7^2x12/24=5206.25

We still have 6000 lbs on the drivers, and plenty of TE to move a train.

Now lets make it a 2-4-2.

1125lbs per wheel and 4500lbs on the drivers, less then our TE. Meaning that if we open up the throttle all the way the wheels will slip.



Now what dose all this have to do with the T1?

Every thing, this was the key problem. Too much of its weight wasn't on the drivers.


Now the other thing I want to pick apart here. Redoing the suspension to redistribute the weight WOULD be a lot of engineering. Its not a matter of adjusting a spring here, tightening a bolt there. Lots of calculations would have to be made.


But considering that the locomotive wont be used as how it was originally intended, I dont think it would matter how they built it.
 
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