Good point.........

A steam locomotive is a glorious beast of a thing, and a monumental PITA at the same time.

Dan Mitchell ============

Oh pishaw! We all love to watch a steamer or more over ride behind one of them.

Have YOU ever actually WORKED on a real one? I have, and will again I hope ... not a lot, granted, but enough . ... And why pisaw? I LOVE steam locos, as my post indicated, But the ARE a PITA!

Dan Mitchell ============

Well, when you consider that it took steam locomotives over 100 years to get to the Big Boy, and it's only taking diesels 60-70 years to catch up, it doesn't seem that strange.

Your definitely right, Dan. Working in engine shops occasionally during the winter, one could see the headache the one "steamer" was compared to the fleet of diesels.

But... They are cool! (Like you also said)

--DW

Your comment made me wonder - one of the major reasons for the transition from steam to Diesel was the greater reliability and lower maintenance requirements. But I have never seen the fine print footnotes to say whether these were based on comparing one F-3 as "a locomotive", or a set 4 of them, to steam. The early Diesels did tend to be sold as 3 or 4 unit sets to match the HP of the bigger steam they were replacing, and only with time did the RRs begin to think of Diesels as modular power units to assemble to meet each train's tonnage requirements. Did GM (et al) pull a fast one with the statistics? Gary Q

"> > John "> "> Your comment made me wonder - one of the major reasons for the transition "> from steam to Diesel was the greater reliability and lower maintenance "> requirements. But I have never seen the fine print footnotes to say whether "> these were based on comparing one F-3 as "a locomotive", or a set 4 of them, "> to steam. The early Diesels did tend to be sold as 3 or 4 unit sets to "> match the HP of the bigger steam they were replacing, and only with time did "> the RRs begin to think of Diesels as modular power units to assemble to meet "> each train's tonnage requirements. Did GM (et al) pull a fast one with the "> statistics? Gary Q

The thing with the diesels is that they are made using the same principles as Henry Ford 'invented' for cars: mass produced on an assembly line. Steam engines tended to be 'hand built', with *each* instance being almost 'unique'. If something broke on a steam engine, a replacement part had to be hand made (I guess some parts were mass produced, but lots weren't). ALL of the parts of a diesel locomotive are mass produced. One can stock a warehouse of common replacement parts. Even if you had to replace one Steam engine with 3 or 4 F-3s, you still have lower maintenance requirements. Esp. if you have a couple of 'spare' F-3s that you can swap in. I don't think there was any sort of one-to-one mapping. Note that although it is possible to double (or triple) head steam engines, MU-ing diesels is a somewhat different thing, since with multiple steam engines you need one engineer per engine and the handling becomes 'tricky'. With MU-ed diesels, you only need a single engineer -- the control linkages (MU cables/hoses) take care of things in an 'automated' fashion -- it is more flexible to have a pile of interchangeable (identical) 1800HP locos that can be MU-ed to get whatever HP you need (in 1800HP increments), than have to have 4-5 classes of *unique* engines, each with a completely different set of spare parts and maintenance issues.

"> "> ">

\/ Robert Heller ||InterNet: snipped-for-privacy@cs.umass.edu

|| snipped-for-privacy@deepsoft.com /\FidoNet: 1:321/153

What's the "we" shit?

*I* for one have no liking for them.

Consider that you have a Big Boy putting out (for comparison) 6000 hp and a 4 unit F-3/7 set, also 6000 hp. Big boy craps out train stops. F unit craps out, train slows down, 2 units crap out train creeps to next terminal or siding.

"What is freedom of expression? Without the freedom to offend, it ceases to exist "

-Salman Rushdie

"Injustice anywhere is a threat to justice everywhere." -Martin Luther King

"A gentleman is a man who can disagree without being disagreeable." Anon

"Revolution in Politics is an abrupt change in the form of misgovernment." Ambrose Bierce

"I don't make jokes. I just watch the government and report the facts"

- Mark Twain

Proudly perverse, eh?

I disagree with this premise.

Steam might have had more absolute HP but they rarely had the opportunity to use it because most of their time was spent at lower than maximum driver rpm. A steam locmotive's functional HP is what it produces at it's median driver rpm. If you have a locomotive that produces 2000hp at 50mph but you use it 90% of the time at 5mph you really have a 200hp locomotive. The extra capacity is wasted and thus irrelevant.

A diesel doesn't need to match a steamer locomotive's maximum output. All it needs to do is match it's median output.

A model of a diesel that functioned the same way as a steam locomotive would be a a locomotive that had several seperate diesel/generators on a common frame and started with one running and to add or subtract more power you had to start and stop subsequent engine/generators.

In a single or twin engine diesel the HP is available NOW not in a few minutes when the wheels get up to maximum rpm.

You miss the point of the multi-engine second generation diesels: to reduce the perceived fixed cost of locomotive building blocks by using bigger blocks. An analogy would be the construction industry's use of a 2 by 10 as a floor joist instead of sistering two 2 by 8 next to each other.

Eric

Dan Mitchell said:

"Only today are INDIVIDUAL Diesels reaching the same power levels at was routine in steam days. It just couldn't be done with the technology of the 40's,

50's, and 60's. The attempt to do so, back then, lead to huge electro-mechanical monstrosities with multiple engines and abominable reliability (Centipedes, U50B & U50C locos, C855's, etc.). Even EMD got

sucked into this mess, with the DD-35 and DDA40X models. Even the twin engined passenger Diesels like the EMD E-units were proportionally troublesome. All are long gone, except for museums and a very few still

in special service (executive trains, etc.). "

Why yes I have worked on a couple as a matter of fact, 4449 for one when I lived in the Portland Oregon area. It was for the American freedom train, and Peggy the little shay that is now on display at the Oregon Forestry center. I was in her gutts (4449) in the boiler and shoveled crap out of the tender where people used it as a toilet, loads of fun. I did a tiny bit of work on SP&S 700 as well. I considered it to be a labor of love.

John

Will Rogers said that.

"It's easy being a humorist when you've got the whole government working for you."

----Will Rogers

What I want to know is who said:

It ain't what a man knows that gets him in trouble. It's what he thinks he knows, but don't".

CH

The torque available at any speed is dependant on the pressure of the steam reaching the cylinders. The steam inlets to the cylinders are restricted, however well designed they are and normally this restriction begins to have an effect at about

20% of maximum speed. 2000hp at 50 mph is going to be more like 4-500 hp at 5mph.

Your limitation is of course the current the traction motors can carry, whereas with a steamloco the limitation is tractive effort/wheel slip.

If you want to make a realistic comparison between steam and Diesel capabilities you would have to compare a steam loco with a bogie mounted chassis or a 1930 rigid frame Diesel.

On Sat, 12 Mar 2005 04:32:37 UTC, Robert Heller wrote: 2000

When a steamer came into the shops it pretty much had to go out with what it brought in, i.e. frame, cylinders, boiler, etc. There were a lot of appliances that could be swapped up to and including tenders but they were still each pretty much one off. Other parts such as pistons, rods and similar stuff could be replaced but they would have to be fitted to that particular loco.

On the other hand a diesel rarely went out with what it brought in apart from the basic structure. It got a rebuilt engine, generator, trucks etc. The railroad had a rotating inventory. As an engine was pulled out it was rebuilt and held for the next unit coming into the shops. The same with the other parts. This was true for the big roads, the smaller ones couldn't afford the luxury of having engine parts like that sitting around.

It ain't what a man knows that gets him in trouble. It's what he thinks he knows, but don't".

His wife?

On Sat, 12 Mar 2005 00:32:30 UTC, "Geezer" wrote: 2000

All you have to do to verify the maintenance stuff is to review what needed to be done with steam. When a coal burner came into the terminal it had to have its ashes dumped, its fire cleaned and restarted, the boiler appliances checked for function and leaks then get refueled, rewatered and turned. All a lot more effort than turning a diesel. Oil burners were simpler.

Boiler maintenance was a constant headache. Remember that a steam locomotive is really a very large bomb. If that boiler blows the damage is significant. As a result boilers were checked often. Staybolts were checked every fifteen days which required a man getting into the firebox and banging on them. That meant dropping the fire and letting the boiler cool down. If a certain number of bolts were broken they had to be replaced which meant removing the jacket and the lagging, removing the broken bolts, installing the new ones, relagging the boiler and replacing the jacket. In addition the boilers had to be washed regularly to preserve the ability to steam. On the Espee the boilers were washed at the time the staybolts were checked. The boiler would also be washed down if it was foaming. Piping to the feedwater heater was critical and no leaks were allowed, more inspection and possible work.

On top of this there was the large mass of reciprocating machinery pounding the track and consequently the drivers and the running gear. Drivers had to be turned frequently because the longer rigid wheelbase of a steamer caused more driver wear than on a diesel. Tires could be turned in place some of the time. The brake heads were removed and replaced with cutters. The eccentric rods were taken down and the loco pulled along a track while air was applied to the brake system to engage the cutters. Again on the Espee Sacramento division engines needed tire turnings every 45 to 50 days while Shasta division engines needed tire turnings every 30 days. It was not a rare occurrence. You don't even want to know what was involved when tires could not be turned in place.

On a diesel that needed wheel turning the bad truck was removed and a replacement installed. The bad truck went through a renewal of whatever was necessary.

In addition to the above was the matter of water quality. It is interesting that it was the desert areas of the western roads that were dieselized first. Getting good water was always a problem so water treatment plants were set up where practical or chemicals were added to the boiler water when water was taken on. This really did become a headache for the railroads.

When it came to maintenance the diesels were much more economical no matter how many units you counted.

Not to be argumentative, but all that business about comparing steam and diesel is really academic, and not much good for anything. It's not that you are wrong, or correct either way. Empirical data is very absolute with regards to the diesel's ability to best steam. If it was not, then you would see a railroad world ruled by steam. The fact is, you do not. Someday, something will come along that renders diesel-electric obsolete, or perhaps that will render the whole philosophy of rail transport obsolete. That's just the way it is.

CH

Steve,

Because real Model Railroaders do not play with diesel locomotives. :) Bruce