USS Monitor Engine

[nlancaster]

I saw this incredible working model

USS Monitor Engine
[ame]http://www.youtube.com/watch?v=VWn8gQ9Ykpk[/ame]

and would love to build something like it some day, but I have a question.

It has 2 valves per cylinder and I wonder how this works. Most steam engines I have seen only have one sliding valve per cylinder and I understand how that works pretty well. Do these valves help the engine with efficancy? and are they needed to make it work or could a similer compact engine be built with only one sliding valve?

 

[steamer]

Welcome Nlancaster,

We are a friendly bunch, tell us about yourself ;D

I believe the owner of that engine is a forum member. He may comment, though that engine has recieved a great deal of press, so he may also stay quite.

There are several members here who could help you with your questions though.

I believe that engine has a riding cut-off.

Dave

 

[rake60]

Welcome to HMEM nlancaster.

Rick

 

[cobra428]

Hi nlancaster,
Welcome to the group wEc1. You sure have picked an ambitious project. I love that engine too. Unbelievably Beautifully. It's a good thing to aspire to. What part of the world are you in?
Tony

 

[nlancaster]

Well, about my self, I am currently building a CNC Routerhttp://cnczone.com/forums/showthread.php?t=44766 from scratch and hope to follow it up with a CNC mill and CNC lathe (not from scratch). Then start building some engines.

I designed this engine and a few others in solidworks, then lost the design to 2 hard drive failures at the same time.

 

[Maryak]

Hi nlancaster,
Welcome to our forum wEc1.

Best Regards
Bob

 

[PTsideshow]

Welcome, can't address your question directly but I will tell you that engine of the Monitor is probably not the best design to start copying off of as few were built and fewer people understood it at the time.
Rich the guy that built that model. Is currently working on a book about the model, and building the model.
Here is a couple of links to the threads on this forum about it Rich's other engines and the article in model engine magazine.
http://www.homemodelenginemachinist.com/index.php?topic=4848.msg49159#msg49159

http://www.homemodelenginemachinist.com/index.php?topic=3509.msg34864#msg34864

Since you didn't say where you are located at, Rich does make most of the major shows and displays his engines in the US.

One of the Village Press magazines also had a building article on how he did the cross over pipe, out of solid not cast pieces.

If you have a question about his engines, you can email him at the addy on his site. And he will get back to you, in a week or so!
glen

 

[nlancaster]

I live in Portland Oregon, and since the demise of PRIME I dont know of any big machinist shows in the NW.

I am not thinking of building an excat duplicate of the engine. Rich's engine is a work of art. I have always been curious about how different engines work and will probably try to build a version of this engine out of wood as an experiment. A large version. I am currently envisioning that it would be about 18inches accross.

I have figured out what the double valves are for on this engine. They control cutoff of steam to the cylinders allowing more expansion of the steam that is in the cylinders.

 

[PTsideshow]

Then this is the book you need it has great drawings and covers most of the modern engines of the time.http://www.astragalpress.com/modern_steam_engines.htm great books and good prices I have a number of the ones dealing with the gauges, whistles and other steam subjects.
glen

 

[hammers-n-nails]

i am by no means an expert on steam engineering because i am new to this hobby but from what reading ive done i have learned that varying the cutoff (the proportion of the stroke during which steam is bein admitted) rather than throttling the steam or reducing its pressure between the boiler and the cylinder is more efficient and reduces wire-drawing of the steam(not sure what the negative effect of this is). since it is not possible to vary the cutoff with a simple slide valve wthout also affecting the exaust opening and closure multiple valves must be employed, as you may kow a corliss engine will have an intake and an exaust valve at both ends of a cylinder for a total of 4. i think ive probably just told you a bunch of stuff you already know but if you need reading material you can go on google books and find alot of books from the 1890's-1920's about steam that have been scaned and can be read off the internet for free ive found it to be very useful in heling me to understand the designs and operation of steam engines. hope ive helped.

 

[Tin Falcon]

Then this is the book you need it has great drawings and covers most of the modern engines of the time.http://www.astragalpress.com/modern_steam_engines.htm great books and good prices I have a number of the ones dealing with the gauges, whistles and other steam subjects.
glen

or download a copy here:
http://www.archive.org/details/modernsteamengin00roserich
Tin

 

[ghart3]

nlancaster, There is the GEARS show in Portland.
Sept 19 and 20 this year.
Also there is the Portland Model Engineers which meets the second Saturday of the month. Also there is a CNC sub group of the PME that meets the first Saturday of the month.
http://216.197.127.227/index.html

 

[nlancaster]

I had completly forgot about GEARS. :

I would love to come to some of the meetings of PME. I have sent you a PM ghart3.

 

[ghart3]

Notification of the Portland Model Engineers meeting is sent out by email and on the Yahoo group portlandmodelengineers

Everybody interested in model engineering is welcome to attend. July's meeting has not been announced yet.

 

[Angsiglar]

I saw this incredible working model

USS Monitor Engine
http://www.youtube.com/watch?v=VWn8gQ9Ykpk

and would love to build something like it some day, but I have a question.

It has 2 valves per cylinder and I wonder how this works. Most steam engines I have seen only have one sliding valve per cylinder and I understand how that works pretty well. Do these valves help the engine with efficancy? and are they needed to make it work or could a similer compact engine be built with only one sliding valve?

The two slide valves ride one atop the other; one is for direction control (ahead-astern) and the other regulates cutoff. In Audels Engineers and Mechanics Guide, Vol. I, there is an explanation of this type of valve as well as a very detailed description of the valve gear and its control. Ericsson was obviously aware of this design (it was quite "new" at the time) and made some improvements. I helped the modeler, Rich Carlstedt, in researching the original engine and I certainly hope he produces the book. The model was about nine years in the maing and a good half of that time was spent in research. If not 100% accurate it is as close to that as is possible. If you are interested in any further info, I live in Portland, OR and may be able to help you - artemis "at" pcez.com