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Discussion Starter #1
On RFD TV this morning nice vidio which brought a few questions to mind.
1) Attached to rear of smoke stack is a 1"? steam pipe what is it's purpose/function?
2) Why does it appear to be two separate feeds of smoke through the stack?
3) Can someone show and explain how the reversing mechanism work (Ralph) maybe. Idon't mean throw the lever in the cab and it goes the other way I would like to understand how that linkage operates.
I have an interest in steam and would really like to better understand.
Dave
 

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I can't speak specifically about the K4...

1. The extra pipe near the stack could be exhaust for the air compressor or dynamo or some other appliance.

2. Some engines had separate exhaust stands (blast pipes) for each side so the exhaust from one cylinder would not apply backpressure to the other one. Since two objects cannot occupy the same place in time or space they would show as slightly offset blasts up the stack.

3. The reverser lever alters which end of each cylinder steam is applied to as the wheel rotate. For one direction it would apply the steam a few degrees ahead of the rotation and for the other it would be a few degrees behind.

Take a look at this web site for some animations of various methods of making engines run.

http://www.keveney.com/Engines.html
 

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Discussion Starter #3
C.T. ,
Thanks for the reply it's a start.
On question 2 I know the steam exhaust through the stack along with the smoke, and your saying the offset feed from the cylinders just makes it appear to be two separate feeds of smoke. In a lot of videos when viewed closely (watch the smoke as it exits the stack) there appears to be a distinct division of the column almost like the stack has a divider in it. Is your explaination also the reason some loco's have two separate stack heads one behind the other?
On question 3 So the reverser lever when thrown actually alters the position of the valves in the cylinders? This is where I get confused and I haven't found any working diagrams to explain this also haven't had the chance to talk with any live steamers

Dave
 

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Posted By dltrains on 09/14/2008 7:32 AM
C.T. ,
Thanks for the reply it's a start.
On question 2 I know the steam exhaust through the stack along with the smoke, and your saying the offset feed from the cylinders just makes it appear to be two separate feeds of smoke. In a lot of videos when viewed closely (watch the smoke as it exits the stack) there appears to be a distinct division of the column almost like the stack has a divider in it. Is your explaination also the reason some loco's have two separate stack heads one behind the other?
On question 3 So the reverser lever when thrown actually alters the position of the valves in the cylinders? This is where I get confused and I haven't found any working diagrams to explain this also haven't had the chance to talk with any live steamers
Dave




I would have to find some photos to maybe explain it better, and right now my brain is befuddled with other problems and I can't remember where they all are. But, some engines even had two separate smokestacks to help keep the exhausts from providing backpressure to the other cylinder, but that wasn't common. Most engines had the exhaust from each cylinder fed to a common outlet aimed up the stack to provide the draft for the fire.


As for valve gear operation, I heartly recommend that you get some books about steam engines.

Here is a list that I included in my series of articles in "Steam In The Garden" Magazine last year about valve gear.

Classic American Locomotives
The 1909 Classic on Steam Locomotive Technology
By Charles McShane
Originally published in 1899 by Griffin & Winters.
The special contents of this edition are copyright
2003 by The Lyons Press
The Lyons Press
Guilford, Connecticut
An Imprint of The Globe Pequot Press
ISBN 1-59228-054-4

The Locomotive Up To Date (1906)
By Charles McShane
Copyright 1906, Griffin & Winters
New York Life Building, Chicago, Ill.
Republished by: Little River Locomotive Company
Townsend, Tennessee
1999

The above two books are actually the same book (I don't understand the date differences in the titles). The only difference being that the second one includes 15 pages of period advertisements for other books by Charles McShane, other publications by Griffin & Winters, locomotives from various well and lesser-known locomotive builders, and artificial limbs from George R. Fuller. (The latter possibly being witness to the danger of working on the railroad in the late 1800s.) I believe "Astragal Press" is presently selling one of these versions of this book (I think Astragal Press has a web site they sell from.)


The Locomotive Up To Date
By Chas. McShane
Copyright 1899 by Chas. McShane
Revised by Chas. L. McShane
Copyright 1920 by Chas. McShane
GRIFFIN & WINTERS
New York Life Building, Chicago, Ill.
1923

This is the best edition of the above three books for technical information, but I know of no modern reprint of it. It must be noted that it is still a book from 1920, changes and improvements continued to occur in the industry, some of which may contradict the information presented. And an interesting note, in the earlier version of the book, Walschaerts’ Valve gear is mentioned as being extensively used on the Belgian State Railways “but probably will not receive much attention from locomotive builders beyond that kingdom�... a scant half page. Whereas, the revised edition devotes nearly 60 pages to the design. Book dealers may have copies of this edition; try Amazon.



Basic Steam Locomotive Maintenance
Developed by D.C. Buell
Copyright 1980 Simmons-Boardman Publishing
Company.
Simmons â€" Boardman Books, Inc.
1809 Capitol Avenue
Omaha, Nebraska 68102


Model Locomotive Valve Gears
By Martin Evans
Model and Allied Publications Limited
VALVE GEAR 5 - 90.indd 4 11/6/06 5:08:49 PM
13/35 Bridge Street, Hemel, Hempstead
Hertfordshire, England
Argus Books Ltd.
14 St James Road, Watford
Revised edition 1981
Copyright 1962, Model & Allied
Publications Limited
Printed in Great Britain by
Staples Printing Group
ISBN 0 85242 769 7
ISBN 0 85242 162 1


La Locomotive A Vapour
By Andre Chapelon
French edition copyright 1952 â€" the Estate of Andre Chapelon
Second French Edition, English Translation
George W. Carpenter C.Eng., M.I.Mech.E.
Copyright 2000 George W. Carpenter and contributors
ISBN 0 9536523 0 0
Published in Great Britain by
Camden Miniature Steam Service
Barrow Farm, Rode, Nr. Bath,
Somerset, BA3 6PS


Valve Gear Simulator
Charles J. Dockstader
P.O. Box 3111
California Valley, CA 93453-3111

This is not a “book� but is an excellent reference, none-the-less. It is a graphical computer program that will run on DOS or Windows based PCs. It can be used to design valve gear systems in any of over 3 dozen different types. It is also a great teaching tool for understanding the function and operation of the various types. If you enjoy watching the gear operate, it is just plain fun to watch! I know this is also available as a free download several places on the web (a quick search for "Dockstader" or "CharlieD" will find it).



Just to further the discussion here... The "valve" (in the valve gear) is used to distribute the steam to opposite ends of the power cylinder, to push the piston from one end to the other and back again. The "valve gear" is used to determine the timing of the valve and that timing determines which way the wheels rotate.

If the "Main Rod" (from the Piston in the Cylinder) to the Wheel, is at the BOTTOM of the wheel rotation then the piston will be at the mid point of the cylinder. Applying steam to the front of the Cylinder will push the Piston backward and that will cause the wheel to rotate to move the locomotive forward. If the steam were applied to the back of the Cylinder then the wheel would rotate the other way and the locomotive would move backward.

If the connection point is at the TOP of the wheel rotation and steam is applied to the front of the Cylinder, pushing the Piston backward, then the wheel will rotate to move the locomotive backward. And likewisee if steam is applied to the back of the Cylinder the Piston would be pushed forward, causing the wheel to rotate to move the locomotive forward.

It all depends on that timing of when steam is applied to which end of the Cylinder. The lever in the cab just moves some connection about 180 degrees from where it is so the timing is reversed to move the locomotive the other way. That "some connection" will vary based on the type of valve gear... Walschaerts’, Baker, Stephenson, Southern, etc., etc., etc.

It gets lots more complicated as you try to achieve better steam utilization (improving the gas mileage!). Every type of valve gear was designed to overcome some shortcomming of the other types, but introduced some other fly in the ointment, causing the next designer to get a better idea and a new valve gear is designed. They were still arguing over it when the Diseasel took over.
 

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Discussion Starter #5
C.T. ,

Thanks again. I'll not only check out the books on your list but also look for your article. Really do appreciate your time and info. I do believe I now have a better understanding of that reverser operation even though I tend to use the wrong terminology. Same goes for the stack configuration.
All the pics I've run across so far only show simple functions, i,e, bubbles for water lines for smoke path. Cut aways of the individual systems would be great and though you may find one or two there certainly aren't many.

Dave
 
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