Noteable Steamers

[Murphy Siding]

QUOTE: Originally posted by futuremodal

Well, let's face facts. We're basically talking buggy whips here anyway. (Hmmm, cones and whips, you're right. It is Madonnaistic.)

But for posterity sake, I thing the best solution would be to go cab-forward, firebox up front supported by the lead truck, then the drivers (whatever combination), and thus no need for a trailing truck, so most of your weight is on the drivers, and the drivers can be as tall as desired. In retrospect, I'm kinda suprised some of the other roads with oil burning engines didn't adopt the cab forward principle, especially GN's Portland bound engines via SP&S, since the operating philosophy of GN was to put as much weight on the drivers as possible.

Now, a cab forward Hiawatha Hudson or a cab forward Challenger, that would have been something. But without the trailing truck, what would their designation have been?

Madonnaistic? You made that one up![:-,]. Now I'm pictureing Madonna w/cones, doing a rope-a-dope on a bicycle built for two. [}:)]

[Anonymous]

I suspect clearance issues and axle loading became more of a problem for many modern fast freight and passenger locos or the roads decided horsepower was more important than absolute weight on the drivers. A number of roads experimented with alloy steel boilers to increase strength and reduce weight. NYC Niagra's even had aluminum cabs and running boards. It also became common practice to move the air pumps to the pilot deck or to the front of the smokebox - even GN did this. Some SP locos had their feedwater heater pumps moved under the cab.

The earliest 4-4-0 and 4-6-0 road locos had a gap between the drivers because they have a 3 point suspension for a smoother ride. I've read that those simple GN and UP 2-8-8-0's were really rough on the crew at anything over 25mph.

[Anonymous]

Well, let's face facts. We're basically talking buggy whips here anyway. (Hmmm, cones and whips, you're right. It is Madonnaistic.)

But for posterity sake, I thing the best solution would be to go cab-forward, firebox up front supported by the lead truck, then the drivers (whatever combination), and thus no need for a trailing truck, so most of your weight is on the drivers, and the drivers can be as tall as desired. In retrospect, I'm kinda suprised some of the other roads with oil burning engines didn't adopt the cab forward principle, especially GN's Portland bound engines via SP&S, since the operating philosophy of GN was to put as much weight on the drivers as possible.

Now, a cab forward Hiawatha Hudson or a cab forward Challenger, that would have been something. But without the trailing truck, what would their designation have been?

[Murphy Siding]

You're talking cones now, and I'm thinking Madonna?[:-,]. I can now visualize what you're saying. Only part that still seems not to work would be the main rod angle. I think the rod would have to be in the same plane as the wheel face,or it would bind, I would think. The answe rof course would be to put the main (only) rod on each side out at the far east side of all 3 of the cone/crank pins. And the west side, of course. I think it would still waddle- it would just look like a Madonna wobble![:o)]

[Anonymous]

There is no inner rod. The main rod angles from cylinder to wheelset #1at the top of the cone, the next side rod from top of cone #1 to top of cone #2, etc.

However, you could have the frontal rods on the interior of the wheels, which would allow the far outer rods complete conage without interferance.

[Murphy Siding]

Arrrrggggg! My head hurts! I realize you drew it***backward. I just presumed you were left-handed.[;)]. If the crankpin extends EAST from wheel #2, it connects with the outter rod about 24" east of the wheel. If the crankpin is at 12:00 position, and I add a cone of metal for support, that cone would have the same diameter as the wheel-say 5' for example. Unfortunately, the crankpin can only connect to wheel #2 at it's own diameter. Any additional "cone" material would be in the way of the inner rod, that connects wheel#2 to wheel #1.
I have to go throw a kid in the tub.

Later

[Anonymous]

Actually, I drew it looking North, so it's actually on the "west" side of the wheel.[:-,]

Rather than me sending another quick draw, visualize it this way - take the driving wheel, add the 2' extended crankpin, then build a cone around the crankpin. The base of the cone will have a "sliver moon" (that's "sliver", not "silver"!) affect on the wheel when looked at in profile. This should have the effect of spreading the force of the rods around nearly the entire circumference of the wheel.

[Murphy Siding]

Crankpin-yes, that's the word I was looking for. Please explain the pyramid a little more. I picture that the crankpin on wheel #2 would have to connect to the "inner" rod just east of the wheel. The connection to the "outter" rod would be 24" further east. It seems to the crank pin would just that- a pin or peg. And yes, I did go back and read your explanation of the changes from the drawing. Conical wheels?

[Anonymous]

Murphy - I explained the changes from the drawing in a previous post. The drawing is exaggerated soley for the purpose of explaining the basics. You are not going to have a 2' long crankpin, rather you will have more like a pyramid or cone extending outward from the wheel, reason #1 to provide component strength, reason #2 to spread the dynamic force over more of the wheel, which should reduce rail pounding.

The second thing I mentioned is angling the main rod outward from the cylinder to the first wheel, and all wheels would be pyramided/coned outward by necessity. Otherwise the first side rod "tight" to the wheel would interfere with the conical wheel.

But as you say, a lot of engineering for what? I cannot answer the main question of whether having large diameter drivers, a large firebox, and no trailing truck to support it (e.g. more weight on drivers) is any advantage over any other steam designs.

[Murphy Siding]

QUOTE: Originally posted by Murphy Siding

QUOTE: Originally posted by futuremodal

QUOTE: Originally posted by Old Timer

Murphy Siding - the four-wheel trailer was necessary to carry the weight of the larger firebox.

This brings to mind a question left unanswered on the T1 thread. Remember the 4-6-0 locomotives? They had a "gap" between the second and third set of drivers to support the firebox. I have assumed that since larger fireboxes required more width than could be afforded between 4' 8.5" gauge, they had to abandon the idea of supporting the firebox with the drivers and relegate that requirement to a supporting truck under the firebox. The question I had is this: Why couldn't the drivers support a wider firebox by extending outward the connecting rods between the driving axle in front of the firebox and the driving axle behind the firebox? That way you have more weight being supported by the drivers (e.g. more traction) instead of a non-driving trailing truck, while still maintaining the advantage of the larger firebox.

For those interested, I received a drawing from Dave in the mail. I was just going to sketch how I saw it not working, but all I got was a drawing in an envelope with a return address! I'd feel kind of silly addressing a letter to "Dave Futuremodal" @xxxxxxxxx.....[;)]

Anyway: a desription based on Dave's drawing. For clarity, consider that the loco is on the tracks, facing north. Starting from the front- pilot wheels / #1 set driving wheels / #2 set driving wheels / 9' x 9' firebox, at axle height / #3 set of driving wheels. There would be 3 driving wheels on each track. On the east side: wheel #1 and Wheel #2 would be connected by a rod, just like 1000's of steamers have been built. The weird part: wheel #2 and wheel #3 would be connected by a rod that goes *around* the firebox. The rod connecting #1 and #2 would be connected as normal,just to the east side(outter side) of the wheels. The rod connecting #2 and #3 would be approximately 24" further east to clear the east side of the firebox. The west side would similar.

I see problems in building a steamer like this. I'll expand my thoughts later when I have time, and my fingers stop throbbing![:)]. Basically, I forsee these issues:

Shear & metal failure

contemporary engineering limitations

*waddling*

buildin a better mouse trap vs. re-inventing the wheel

Beyer-Garret (sp?) locomotives

Later

I'm back [:)]

Shear and metal failure : The rods on wheels #2 & #3 would be about 24" out (east in our example) from the wheel. By neccessity, there would have to be a *peg*(?) about 24" long attatched to wheel #2. That peg would have the rod from wheel #1 attatched to it near the wheel face. The rod from wheel #3 would be attatched to the peg at the east end of the peg. It's not hard to forsee the forces involved wearing on the peg and shearing it off where it meets wheel #2.

Contemporary engineering limitations: In the heyday of steam,there were no computers,or calculators, or adding machines or even ball point pens for that matter[:p]. It would have taken a long time with a slide rule to figure out how to keep the *outter* rods and the pegs in one piece.

"Waddling": All that weight swinging about at the outside edges of the design would have to cause some wicked shimmying! Think of Muhamed Ali sitting on the back seat of a bicycle built for two, doing a "rope a dope" boxing routine.

Mousetrap: There were a lot of easier ways to accompli***he same thing, without having to overcome engineering hurdles. The 2 or 4 wheel trailing truck to support the firebox, for example.

Beyer-Garret: I still haven't looked up the spelling. These I believe were British designs for meter guage track in Africa? Imagine a 4-2-firebox-2-4 locomotive, and you've got it.

In general: It probably would work. It probably wouldn't be worth the hassle. Oh well![:)]

[tree68]

Wow - lots to read here - should have picked up on it earlier!. I think the problem with extending the drivers comes down to two things - weight and strength. You can increase strength with a larger cross section, but that adds weight, which contributes to dynamic augment, as mentioned.

[nanaimo73]

QUOTE: Originally posted by Murphy Siding

Anyway: a desription based on Dave's drawing. For clarity, consider that the loco is on the tracks, facing north. Starting from the front- pilot wheels / #1 set driving wheels / #2 set driving wheels / 9' x 9' firebox, at axle height / #3 set of driving wheels. There would be 3 driving wheels on each track. On the east side: wheel #1 and Wheel #2 would be connected by a rod, just like 1000's of steamers have been built. The weird part: wheel #2 and wheel #3 would be connected by a rod that goes *around* the firebox. The rod connecting #1 and #2 would be connected as normal,just to the east side(outter side) of the wheels. The rod connecting #2 and #3 would be approximately 24" further east to clear the east side of the firebox. The west side would similar.

So wheel #2 would have open access to wheel #3 ?

[GN-Rick]

Murphy,
I have a great resource that has taught me a
huge amount about what makes steam locomotives
tick. It is a 1941 issue of the AAR's publication "Locomotive
Cyclopedia". It covers everything-from boilers, frames and
other major things down to piston ring packing and insulating
tape. I have learned so much by looking this over. If you can
find one-or another early year-grab it if you want to understand
steam.

[Murphy Siding]

QUOTE: Originally posted by futuremodal

QUOTE: Originally posted by Old Timer

Murphy Siding - the four-wheel trailer was necessary to carry the weight of the larger firebox.

This brings to mind a question left unanswered on the T1 thread. Remember the 4-6-0 locomotives? They had a "gap" between the second and third set of drivers to support the firebox. I have assumed that since larger fireboxes required more width than could be afforded between 4' 8.5" gauge, they had to abandon the idea of supporting the firebox with the drivers and relegate that requirement to a supporting truck under the firebox. The question I had is this: Why couldn't the drivers support a wider firebox by extending outward the connecting rods between the driving axle in front of the firebox and the driving axle behind the firebox? That way you have more weight being supported by the drivers (e.g. more traction) instead of a non-driving trailing truck, while still maintaining the advantage of the larger firebox.

For those interested, I received a drawing from Dave in the mail. I was just going to sketch how I saw it not working, but all I got was a drawing in an envelope with a return address! I'd feel kind of silly addressing a letter to "Dave Futuremodal" @xxxxxxxxx.....[;)]

Anyway: a desription based on Dave's drawing. For clarity, consider that the loco is on the tracks, facing north. Starting from the front- pilot wheels / #1 set driving wheels / #2 set driving wheels / 9' x 9' firebox, at axle height / #3 set of driving wheels. There would be 3 driving wheels on each track. On the east side: wheel #1 and Wheel #2 would be connected by a rod, just like 1000's of steamers have been built. The weird part: wheel #2 and wheel #3 would be connected by a rod that goes *around* the firebox. The rod connecting #1 and #2 would be connected as normal,just to the east side(outter side) of the wheels. The rod connecting #2 and #3 would be approximately 24" further east to clear the east side of the firebox. The west side would similar.

I see problems in building a steamer like this. I'll expand my thoughts later when I have time, and my fingers stop throbbing![:)]. Basically, I forsee these issues:

Shear & metal failure

contemporary engineering limitations

*waddling*

buildin a better mouse trap vs. re-inventing the wheel

Beyer-Garret (sp?) locomotives

Later

[Murphy Siding]

QUOTE: Originally posted by GN-Rick

Firemen were absolutely necessary with a power stoker. As mentioned,
the fireman (and engineer) had to monitor boiler water level and ane
turn on the injector when needed to replenish. The fireman alse adjusted
the steam jets on the stoker to throw coal where desired in the firebox.
If you have ever noticed in a cab view, a cluster of 6 smallish valve
wheels in front of the fireman's seat arranged in an upside down
triangle, those are the jet controls for the stoker. Each jet blasts coal
from the firing table or distributing plate of the stoker in it's own individual
direction. How far open the valve is determines how powerful the
blast is and how far forward in the firebox the coal is thrown.
the controls are arranged like this:

Upper row:--------O---------O------------O
controlling: left rear main jet right rear
center row--------------O-----------O
controlling: left front right front
bottom:-----------------------O
controlling: center
The power stoker did not replace the fireman. It was a tool for him
to use in the performance of his job and made large steam locos
viable from a standpoint of being able to keep up with the demands
of coal while working hard. Hope this helps.

Yes, you answered my question. I couldn't quite visualize how the fireman could control the fire with a mechanical stokker. I had pictured it more as a pipe, with an on and off switch.

Thanks

[Gunns]

Hi All,
I'm biased toward big 4-8-4s, <Grin>
And ours is oil fired. Here is a comparison sit for 4-8-4s that are running or close to running.
http://www.sbrhs.org/484com.html
Gunns

[GN-Rick]

Firemen were absolutely necessary with a power stoker. As mentioned,
the fireman (and engineer) had to monitor boiler water level and ane
turn on the injector when needed to replenish. The fireman alse adjusted
the steam jets on the stoker to throw coal where desired in the firebox.
If you have ever noticed in a cab view, a cluster of 6 smallish valve
wheels in front of the fireman's seat arranged in an upside down
triangle, those are the jet controls for the stoker. Each jet blasts coal
from the firing table or distributing plate of the stoker in it's own individual
direction. How far open the valve is determines how powerful the
blast is and how far forward in the firebox the coal is thrown.
the controls are arranged like this:

Upper row:--------O---------O------------O
controlling: left rear main jet right rear
center row--------------O-----------O
controlling: left front right front
bottom:-----------------------O
controlling: center
The power stoker did not replace the fireman. It was a tool for him
to use in the performance of his job and made large steam locos
viable from a standpoint of being able to keep up with the demands
of coal while working hard. Hope this helps.

[Murphy Siding]

The automatic stoker made life easier for the fireman, but he was still neccessary then?

[bobwilcox]

QUOTE: Originally posted by Murphy Siding

Question about automatic stokers: I understood the fireman had to shovel the coal out of the tender, and into the fire box. He had to know how much coal to put in, and where on the grate to put it, as deemed neccesarry by running conditions. How did an automatic stokker replace the fireman? Did the stokker just bring the coal forward, and the fireman placed it on the grate? Or,did someone (the engineer?) just have to turn a lever?

I think the automatic stoker would throw the coal in an even pattern around the firebox. The fireman not only needed to make sure the stoker was working correctly he had to mind the water supply to the boiler. If the coal supply stops the locomotive runs out of steam and stops, if the water stops the locomotive ruptures it's crown sheet and explodes!

[Murphy Siding]

Question about automatic stokers: I understood the fireman had to shovel the coal out of the tender, and into the fire box. He had to know how much coal to put in, and where on the grate to put it, as deemed neccesarry by running conditions. How did an automatic stokker replace the fireman? Did the stokker just bring the coal forward, and the fireman placed it on the grate? Or,did someone (the engineer?) just have to turn a lever?

[Murphy Siding]

QUOTE: Originally posted by futuremodal

QUOTE: Originally posted by timz

Okay, see if this is what you mean. The two trailing axles are maybe 15 feet apart (and so the trailing siderods are 15 ft long). The firebox is down at axle level? and it's maybe 8 feet wide? It's all ahead of the flange of the rear driver and behind the next-to-rear driver? And the pins on the two rear driving axles are lengthened so their siderods are farther out from the centerline of the engine, far enough to clear the firebox.

I guess the siderods ahead of the next-to-rear driver would be in the normal places, so the main rod could still be outboard of them? Or the main rods would always have to drive the leading axle?

Where would the engine's frame be, between the two rear drivers-- below the firebox? Don't forget we need an ashpan too.

Yes. Someone more interested in steam than I would have to fit in all the specs, I'm more interested in the trade off question - more weight on drivers vs more steam. GN rick pointed out the 2-8-8-0 of GN, which had smaller drivers supporting the firebox above, yet which still could run at near passenger speeds. But if the desire was for greater speeds via larger drivers while still keeping weight over the drivers and greater steaming requirements, would this oddball idea work?

Dave-got your drawing. It makes sense now. Give me a little time to study it.
Thanks

[Anonymous]

Regarding drivers underneath the firebox on modern locos, the type of coal used also affects what type of firebox can be used. UP fireboxes are long with lots of grate area, but relatively shallow, so it's possible to fit reasonably large drivers underneath. The Berkshire is usually talked about as being first, but the UP 4-12-2's had a large firebox with the last pair of 67" drivers beneath it. Challengers with 69" drivers were similar, while Big Boys had 2 pairs of 68" drivers beneath the firebox. The Allegheny and some other eastern locos needed much deeper fireboxes for the hotter burning coal they used, so the entire firebox had to be supported by a trailing truck.

[nanaimo73]

Sounds good to me. Thanks for the answer,I've been wondering about that for awhile.

[Anonymous]

Nanaimo73: You're talking about the drivers being quartered - in other words, the crankpins on one side being 90 degrees from those on the other. This is true of two-cylinder simple locomotives; three-cylinder engines had the three cranks 120 degrees apart (you only saw the outer ones; the middle one was, of course, between the frames).

Most railroads had the crankpins on the right side leading; in other words, when the pins on the right side were on the front dead center, the left side was on the top quarter; the left side therefore followed the right.

The PRR was the most notable exception to this rule; most of its engines used left hand lead.

There was a factor in the counterbalancing of a steam locomotive called "dynamic augment". This is the effect of piston thrusts on one side of the locomotive on the balancing on the opposite side. A peculiarity of this factor caused the side that had the lead (on most locomotives, the right side) to tend to pound the rail more than the other side.

Someone advanced the theory (since no one has put it into print as an actuality) that the PRR used left hand lead so that the left side would pound the rail more than the right side. Since the left side is the inside on multiple track, and the track structure is weaker on the outside, this would cause the hardest pounding to occur in the strongest area of the roadbed. PRR had more multiple track than most railroads.

This may be all wet, but it was advanced as a theory a good many years ago.

Old Timer

[Anonymous]

QUOTE: Originally posted by timz

Okay, see if this is what you mean. The two trailing axles are maybe 15 feet apart (and so the trailing siderods are 15 ft long). The firebox is down at axle level? and it's maybe 8 feet wide? It's all ahead of the flange of the rear driver and behind the next-to-rear driver? And the pins on the two rear driving axles are lengthened so their siderods are farther out from the centerline of the engine, far enough to clear the firebox.

I guess the siderods ahead of the next-to-rear driver would be in the normal places, so the main rod could still be outboard of them? Or the main rods would always have to drive the leading axle?

Where would the engine's frame be, between the two rear drivers-- below the firebox? Don't forget we need an ashpan too.

Yes. Someone more interested in steam than I would have to fit in all the specs, I'm more interested in the trade off question - more weight on drivers vs more steam. GN rick pointed out the 2-8-8-0 of GN, which had smaller drivers supporting the firebox above, yet which still could run at near passenger speeds. But if the desire was for greater speeds via larger drivers while still keeping weight over the drivers and greater steaming requirements, would this oddball idea work?

[timz]

Okay, see if this is what you mean. The two trailing axles are maybe 15 feet apart (and so the trailing siderods are 15 ft long). The firebox is down at axle level? and it's maybe 8 feet wide? It's all ahead of the flange of the rear driver and behind the next-to-rear driver? And the pins on the two rear driving axles are lengthened so their siderods are farther out from the centerline of the engine, far enough to clear the firebox.

I guess the siderods ahead of the next-to-rear driver would be in the normal places, so the main rod could still be outboard of them? Or the main rods would always have to drive the leading axle?

Where would the engine's frame be, between the two rear drivers-- below the firebox? Don't forget we need an ashpan too.

[Anonymous]

QUOTE: Originally posted by timz

"Why couldn't the drivers support a wider firebox by extending outward the connecting rods between the driving axle in front of the firebox and the driving axle behind the firebox? That way you have more weight being supported by the drivers (e.g. more traction) instead of a non-driving trailing truck, while still maintaining the advantage of the larger firebox."

Hmm... you're proposing the rear driver would be 20 or 30 feet behind the driver ahead of it, with 20-30-ft side rods? And a firebox that's less than 4 ft wide, and 20-30 feet long?

Or is your firebox to be above the drivers, not between them? If it's above the drivers, why are the siderods a problem?

Hmmm. "20 or 30 feet"? I was thinking 8 to 9 square feet of firebox space, so with 6 foot drivers that's about 15 feet of side rod extended widthwise a few feet each side. By comparison, the main rod of a 4-8-4 with 80" drivers looks to be about 10 feet long. Would another 5 feet make such a 15' side rod untendable? I don't know. My guess is that it depends on the ultimate trade off - namely more weight on drivers for more tractive effort but with possibly unwieldy and too heavy side rods vs the larger fireboxes supported on trailing trucks for greater steaming but less weight on drivers.

Note to Murphy - in my drawing I should have adapted the main rods from the cylinders running at a slight angle from the cylinder to the first driver, with the connecting pin replaced by a larger " half-pyramid" shaped connection, with a greater surface area of the drivers being the "base" of the half-pyramid (convex to the axle center) and the top of the half pyramid the side rod connection.

[Murphy Siding]

QUOTE: Originally posted by timz

"Why couldn't the drivers support a wider firebox by extending outward the connecting rods between the driving axle in front of the firebox and the driving axle behind the firebox? That way you have more weight being supported by the drivers (e.g. more traction) instead of a non-driving trailing truck, while still maintaining the advantage of the larger firebox."

Hmm... you're proposing the rear driver would be 20 or 30 feet behind the driver ahead of it, with 20-30-ft side rods? And a firebox that's less than 4 ft wide, and 20-30 feet long?

Or is your firebox to be above the drivers, not between them? If it's above the drivers, why are the siderods a problem?

I had the same problem visualiizing the question. futuremodal is mailing me a drawing. I'll let you know what I find out.

[espeefoamer]

QUOTE: Originally posted by Murphy Siding

I've mentioned that steam locomotives didn't do much for me,but I have been doing quite a bit of railroad reading recently-so they might grow on me.[:)]

In the steam era, it appeared that nearly every railroad had almost custom designed engines, specifically for it's route. I'm familiar with some of the more famous ones:Big Boy, Challenger,Berkshire,J-1(? N&W), and a few others. What are some of the other well known types that other railroads had? And can you explain to this *diesel* fan what the signifigance of the type was? I still have a hard time seeing the difference between two similar types.

Thanks!

You should chase or ride a few steam fantrips.You will be hooked for life[:)].I used to feel the same way about steam that you do until I first saw the freedom train and chased it for two days[:p].