The second video I posted above is of her first run out of Irondale to Chattanooga....she got moving pretty well, I'd say 60-65mph. And in the Hope well video "Queen of the Fleet" they were pacing her at over 75mph with Mr. Claytor at the throttle. No question the J's could haul the mail but if any steam were to break the century mark in this country the FRA would have kittens...and someones head.
As for the Mallards record there are some big differences between the Mallard and the 611, weight,BP,TE, piston size ect.
Too bad she's not around to be put to the test, and as suggested, it would
have to be VERY unofficial...say a night time run. But I say give me
some straight level track out in western Ohio, or Indiana, and give me PRR
5500 with Dick Graham at the throttle, and you'll have the REAL world
steam speed record! One twenty six is peanuts!
have to be VERY unofficial...say a night time run. But I say give me
some straight level track out in western Ohio, or Indiana, and give me PRR
5500 with Dick Graham at the throttle, and you'll have the REAL world
steam speed record! One twenty six is peanuts!
The PRR's one-time Ft. Wayne Div. speedway would need a serious re-building afore you take the 5500 out there to set speed records. As of now, you'd be lucky to see 40 mph with any engine. Sad.
quote:The rule of thumb is 1 MPH per inch of driving wheel diameter.
My understanding is that this is the OPTIMUM, ie, most efficient and smoothest operating, top speed.
Here's what happens when a steam locomotive reaches her "top end."
Uncontrolled slip
The engine stripped herself of all her running gear and rods, and cracked her cylinder saddle, among other damage and injuries caused.
Uncontrolled slip
The engine stripped herself of all her running gear and rods, and cracked her cylinder saddle, among other damage and injuries caused.
quote:I also wonder if having a quadrant-type reverse lever (instead of a screw) would have allowed the engineer to simply center the reverser and shut her down?
That wouldn't have mattered, since the engine will keep right on running with the gear "on center", due to the "lap & lead". Essentially the same effect as built in "initial timing advance" in the distributor of an internal combustion gasoline engine.
614 has gone REALLY fast before too...
What authenticated timings for 614 does anyone out there have? Thanks.
One other reason that the infamous "Blue Peter" slip went out of control is due to her design. It is an older locomotive with a single-valve dome throttle. The throttle controls the flow of steam INTO the superheaters. Once steam is admitted into the superheaters it has an unrestricted path to the cylinders.
This is opposite of the way a multiple-valve front end throttle works. With a front end throttle, the throttle valve is on the OUTPUT side of the superheaters. If the locomotive pulls water, the flow of steam can still be controlled by the throttle because it is controlling the OUTPUT of steam from the superheaters.
If a steam engine with a dome throttle pulls water, the superheaters act as a secondary boiler! Even if the engineer could have gotten the throttle closed, the slip would have continued for a while because once the water got past the throttle, the superheaters flashed it into steam and it flowed - unrestricted and uncontrolled - to the cylinders. This was one of the reasons that the front-end throttle came into use, because this dangerous situation could not develop with a front-end throttle design.
This is opposite of the way a multiple-valve front end throttle works. With a front end throttle, the throttle valve is on the OUTPUT side of the superheaters. If the locomotive pulls water, the flow of steam can still be controlled by the throttle because it is controlling the OUTPUT of steam from the superheaters.
If a steam engine with a dome throttle pulls water, the superheaters act as a secondary boiler! Even if the engineer could have gotten the throttle closed, the slip would have continued for a while because once the water got past the throttle, the superheaters flashed it into steam and it flowed - unrestricted and uncontrolled - to the cylinders. This was one of the reasons that the front-end throttle came into use, because this dangerous situation could not develop with a front-end throttle design.
None past the 79MPH speed limit from NJT, of course 
Bring back the Milwaukee Road and the Hiawatha F7s.
quote:"That wouldn't have mattered, since the engine will keep right on running with the gear "on center", due to the "lap & lead". Essentially the same effect as built in "initial timing advance" in the distributor of an internal combustion gasoline engine."
The 'lap and lead' or "combination" lever used with Walchaert and Baker valve gears.
quote:is it an art to get the engine exhaust square on a steamer, You hear many with the I think I can sound but I know the 765 is now very square.
Sounds like you are confusing out of quarter with whether the valves are set properly. As usual, it is difficult to understand your typing, sentence structure, and punctuation/capital letters.
There are two aspects to setting steam locomotive valves correctly.
One is the valve TIMING, which can be affected by the quartering of the drive wheels and the valve gear settings. If the rhythm of the exhausts beats is not perfectly even (there may be a longer pause between two beats, or two beats hit closer together than the others) then the valves are said to be out of TIME.
If one (or more) exhausts are noticeably louder or softer than the others, then the valve POSITION is not right. One of the valves is too far forward or back from the correct center position where it should be.
I guess you could say that it is an art to get the valves on a steamer set perfectly. However there are very precise measuring points in the valve gear that can be observed to determine how to adjust things to make it right. "Trailing" the valves is the procedure used to measure exactly where the valves are as they move through a power stroke. Trailing the valves is a procedure where a dead steam locomotive is slowly moved (by another locomotive) through one revolution of the drive wheels with an apparatus attached to the valves that makes marks on a card that shows the position of the valve throughout the stroke. By reading those cards and taking measurements on the card and the valve involved, a mechanic can quickly see whether the valves are in the right position throughout the stroke and whether the valve gear is moving them properly. Knowing what adjustments are needed in the valve gear to make things right is where the "art" comes into play.
It's like the guy who takes his car to a mechanic because it is idling roughly. The mechanic opens the hood, takes out a screwdriver, adjusts the idle mixture and the car smooths right out. He closes the hood and says to the driver, "That will be ten dollars." The driver says, "TEN DOLLARS! All you did was turn a screw! It didn't take you 30 seconds to do that!" To which the mechanic calmly replied, "It's only 50 cents for turning the screw. The other $9.50 is for knowing which screw to turn, which way and how far."
Same for setting the valve gear on a steamer. The really GOOD guys, like Robert Franzen, the guy who set the valves on the 765, know which adjustment to make, which way to adjust it and how far it should go.
One is the valve TIMING, which can be affected by the quartering of the drive wheels and the valve gear settings. If the rhythm of the exhausts beats is not perfectly even (there may be a longer pause between two beats, or two beats hit closer together than the others) then the valves are said to be out of TIME.
If one (or more) exhausts are noticeably louder or softer than the others, then the valve POSITION is not right. One of the valves is too far forward or back from the correct center position where it should be.
I guess you could say that it is an art to get the valves on a steamer set perfectly. However there are very precise measuring points in the valve gear that can be observed to determine how to adjust things to make it right. "Trailing" the valves is the procedure used to measure exactly where the valves are as they move through a power stroke. Trailing the valves is a procedure where a dead steam locomotive is slowly moved (by another locomotive) through one revolution of the drive wheels with an apparatus attached to the valves that makes marks on a card that shows the position of the valve throughout the stroke. By reading those cards and taking measurements on the card and the valve involved, a mechanic can quickly see whether the valves are in the right position throughout the stroke and whether the valve gear is moving them properly. Knowing what adjustments are needed in the valve gear to make things right is where the "art" comes into play.
It's like the guy who takes his car to a mechanic because it is idling roughly. The mechanic opens the hood, takes out a screwdriver, adjusts the idle mixture and the car smooths right out. He closes the hood and says to the driver, "That will be ten dollars." The driver says, "TEN DOLLARS! All you did was turn a screw! It didn't take you 30 seconds to do that!" To which the mechanic calmly replied, "It's only 50 cents for turning the screw. The other $9.50 is for knowing which screw to turn, which way and how far."
Same for setting the valve gear on a steamer. The really GOOD guys, like Robert Franzen, the guy who set the valves on the 765, know which adjustment to make, which way to adjust it and how far it should go.
Love the steam debates and fascinating info!
Thanks Rich, always love your detailed answers.
