# Rotary valve twin steam engine



## max corrigan

This is my rendition of the rotary valve engine in plans, i would like to thank whoever posted them it is a great little engine and runs well
My version was made from scrap cast iron,stock material, and anything else that fitted the bill
Here are a couple of pictures, then i will try the vids
Regards Max

Ps looks like the two attachments are of the same picture sorry!


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## Maryak

Max,

That's one fine looking engine. :bow: :bow:

Best Regards
Bob


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## HS93

that looks great , what bore and stroke is it? 

where did you get the plans for it

thanks

peter


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## ironman

Beautiful finish on the parts. I built 2 of these. Even my sloppy first one runs great. 
Really like your intake and valve. Keep up the good work and pictures. Ironman


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## SAM in LA

The dark color with the polished brass looks really nice.

SAM


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## Philjoe5

Nice work Max. Great detail work. I like the black/brass combo. :bow:

Cheers,
Phil


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## Blogwitch

Can anyone help me in locating the plans for this engine please?

Bogs


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## max corrigan

A couple more pics 
Peter HS93 the bore is 9/16" and stroke is 7/16
John (bogs) and Peter the plans are under "Elmers Steam Engine Plans" open page scroll down to Steam Engine Plans" (not Steam Engine Plans 2) scroll down on right hand side you will see Rotary Valve Engine
let me know if you get them
I'm gonner try the video in seperate post having trouble getting files in one post that's the problem not understanding computers 
Regards Max.....


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## HS93

thank you for that I will have a look .

Peter


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## max corrigan

I hope this Vid comes out OK, i first ran the engine on air, but steam gives it another dimension, I think!
 The vid seems to show the engine running anti clockwise which is not the case, and the faster the revs the slower the valve linkage appears to move! very strange!
This engine can run at quite high revs, so much so, the grub screws i made (with slotted heads) flew out! hence the odd looking screws you might notice
i think i mentioned my bad steaming layout, you will see one exhaust blasting on the oiler which keeps it nice and hot! not quite the right idea idea :-[
There were no leaks on the engine other than the ends of the valve rod, which were as in the plan, i put oil grooves on the pistons "alla Stuarti used 0 rings under the manifold, and tel's method for sealing cylinder head ie PTFE tape twined around head studs, no gaskets, as i said no leaks most of the steam is coming from the safety vale on the boiler and the exhausts
I did do a spasmodic build arrangement as i went along with pics, but now it would be retrospect ??? but can attempt to post if anyone is interested 
Regards Max


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## Blogwitch

Many thanks for that Max.

Congratulations on a good runner.


John


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## ironman

Bogs, disregard my previous post, the likn is not right. Sorry bout that. It is as stated on John tom's site. 
good running little 2 cylinder. Be nice to have a reverser on it. Maybe you can do that and post it. Have a great day. Ironman


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## Aquarius21

Hi, I have barely begun to do my first build and it is of this engine. A lovely job done on yours!
Question. Where could one find plans on making a boiler like yours? thanks Quincy


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## rake60

Very nicely done Max! Thm:

Rick


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## arnoldb

Well done Max :bow:

Your "ostrich" sure has a reason to smile with it's head held high ;D

Regards, Arnold


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## max corrigan

Thanks everyone for your kind comments! it certainly gives a good feeling to be among such an illustrious bunch as you all are, and all the things i've learned from this site are invaluable for novice machinist like me
Aquarias21 i can't supply plans for the boiler as it is a Stuart boiler i bought on ebay a couple of years ago for less than half the price it would have cost from Stuart's if you look at the follow up engine on photbucket, you will see it harnessed to a Stuart mill engine that was my first build,
And good luck with your build of this engine, if you need help don't be afraid to ask, especially the valve rod! don't ask me how i know  i made three of them before i got it right
Arnold yes the ostrich does look happy, but he might replaced with this engine that will knock the smile off 'is kite 
Regards Max


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## BenPeake

I enjoyed watching your engine running - lots of movement. Bravo! Are you going to take up the reversing lever challenge?


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## max corrigan

BenPeake  said:
			
		

> I enjoyed watching your engine running - lots of movement. Bravo! Are you going to take up the reversing lever challenge?


Ben i did think of a reverser valve but could'nt find any plans! was also thinking of a whistle for some strange reason ???
Thanks for your comment Regards Max.............


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## Anatol

Hi all
Max,  you made a pretty engine.
I was looking at the original plans for this engine -then I saw this (old) thread.
Does anyone know which magazine (or book)  it was published in? Does anyone know  who designed it? Was it Verberg? Its very like the  Stuart Sirius (isn't it?), but with a Corliss type valve.
  Looking at the plans I was wondering about possible design changes.
1. could you put the flywheel between the cranks? I'm thinking of a flywheel in two halves, screw-clamped on the shaft.
2. why not make the valve crank  longer and dispense with the complex linkage?
3. why not have separate inlet and outlet ports? This would give more surface area on the valve shaft for sealing, and insulate inlet steam from the cooling exhaust.


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## adolfgalland

Anatol,   The plans for this engine were in the December 1961 Popular Science magazine. It starts on page 144 and was from a guy named Henry Frostick.

Gary


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## Anatol

Thanks Gary! I found it via google docs. 
I've been thinking a lot about this design. Can anyone explain to me why the valve linkage has to be so complex? Surely a longer crank, and/or shorter valve lever arm, would permit removal of the middle linkage?


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## adolfgalland

Anatol,  I am sure the center linkage could be removed rather easily if someone wanted to. Some of us say  ( The more movement the better ). When I did my version of the Rudy Kouhoupt beam engine from the Aug 1969 addition of Popular Mechanics I did the opposite of what your asking and added another linkage.       Gary


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## Anatol

adolfgalland said:


> I did the opposite of what your asking and added another linkage.       Gary



Hi Gary
did you do this for mechanical reasons or for aesthetic reasons?


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## Anatol

adolfgalland said:


> Anatol,   The plans for this engine were in the December 1961 Popular Science magazine. It starts on page 144 and was from a guy named Henry Frostick.
> 
> Gary



Gary
this link 
http://www.john-tom.com/MyPlans/Steam Engines/RotaryValveEngine.pdf
is the one I previously had for the identical text, not sure what magazine its from. 
but Frostick's name isn't on it. 
interesting


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## adolfgalland

Anatol,  I find quite often that when I make engines from someone's plans that I end up changing this or that like in the following photos. The original was from a guy named David Kerzel. Mine has a rotary valve rather than CO2 design  As for my beam engine I changed the linkage and a another thing or two just for the heck of it.    Gary


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## Anatol

adolfgalland said:


> Anatol,  I find quite often that when I make engines from someone's plans that I end up changing this or that like in the following photos. The original was from a guy named David Kerzel. Mine has a rotary valve rather than CO2 design  As for my beam engine I changed the linkage and a another thing or two just for the heck of it.    Gary
> 
> View attachment 101688
> View attachment 101689



Gary
I looked for plans to this Kerzel engine but could not find. Do you know where I can find?
I don't know anything about CO2 engines, Howard they different in operation from Steam/compressed air?
I'd like to know more about your  rotary valve
thanks


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## fcheslop

John tom
http://www.john-tom.com/html/SteamPlans3.html


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## adolfgalland

Anatol,  If you found David's plans on john-tom then you probably have seen how the co2 type engines work. If not the top of the piston has a pin which lifts a ball off a seat at TDC which gives it a shot of air to drive the piston down. In a rotary valve like mine part of the crankshaft has flats milled which line up with ports in the block to allow air in and out. Not sure if I explained that very well. One photo is of a version David's engine showing the pin and ball design. The other shows a rotary valve from Rudy Kouhoupt's  Radial 5.  I went with the rotary valve because you can run the engine on much less air pressure for a slow running engine.      Gary


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## Anatol

adolfgalland said:


> Anatol,  If you found David's plans on john-tom then you probably have seen how the co2 type engines work. If not the top of the piston has a pin which lifts a ball off a seat at TDC which gives it a shot of air to drive the piston down. In a rotary valve like mine part of the crankshaft has flats milled which line up with ports in the block to allow air in and out. Not sure if I explained that very well. One photo is of a version David's engine showing the pin and ball design. The other shows a rotary valve from Rudy Kouhoupt's  Radial 5.  I went with the rotary valve because you can run the engine on much less air pressure for a slow running engine.      Gary
> 
> View attachment 101987
> View attachment 101988



Thanks Gary

"the top of the piston has a pin which lifts a ball off a seat at TDC"

ah, so its a 'bash valve'. I've looked at lots of plans. I've noticed authors seldom give a basic technical summary and you halve to work it out from the drawings.  

"In a rotary valve like mine part of the crankshaft has flats milled which line up with ports in the block to allow air in and out."

So the crankshaft functions as the valve. I'd thought about this kind of solution, it certainly reduces moving parts. I wonder why one does not see it so often?

thanks again

"a rotary valve from Rudy Kouhoupt's  Radial 5."

Is this similar to the one you made? What are the downsides? How does it seal? How does it wear? What metals did you use for valve and seat? I see you used a delrin position, so presumably this is not designed to run on steam? 
thanks again.


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## terryp

Wow, nice looking engine. I am in the process of building the same engine and thought it would be the only one in the world! Not! If I can figure out how to post photos I will do so here. Soooooooo this is an Elmer engine?


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## adolfgalland

I think I kind of got this thread hijacked and I did not mean to. If I should stop adding to this thread would someone let me know.
Anatol,  Sometimes the rotary valve is part of the crank. In Rudy's case he called it ( the valve ) but I think of it as the rear half of the crank. On the twin cylinder that this thread featured I think of it as a camshaft with flats rather than lobes although the author said he filled the shaft rather than milled it. The seal is as good as you are at making a shaft a perfect fit in a bore. The materials can be different combinations. I typically use either steel/brass or brass/aluminum. My engines get very little running time and I would guess they have little to no wear. Did you mean to say Delrin piston. That engine is not mine but rather some other guys version of Dave's. I do use some of the high performance plastics for pistons on most of my engines because they are self lubricating but you do need to pay attention to their  coefficient of thermal expansion so your engine won't seize when the room temperature rises. Teflon has the best coefficient of friction but the worst for expansion. I do not run any engines on steam.
terryp,  If you are referring to the V-twin it is not a Elmer engine but rather David Kerzel's. Mine was copied from his plans but with many changes such as double scale, rotary valve, square cylinders and cylinders in line like a Harley rather than staggered like David's.       Gary


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## Anatol

Gary
"I think I kind of got this thread hijacked and I did not mean to. If I should stop adding to this thread would someone let me know."
I started a thread on rotary valves at
https://www.homemodelenginemachinist.com/threads/rotary-valves.30193/
we can continue the conversation there. 

"I do use some of the high performance plastics for pistons on most of my engines because they are self lubricating but you do need to pay attention to their coefficient of thermal expansion so your engine won't seize when the room temperature rises. Teflon has the best coefficient of friction but the worst for expansion."

right, and it gets squishy. 

" I do not run any engines on steam."

I'm planning to run on steam so my interest is in self-lubricating  non-hydroscopic materials with minimal thermal expansion. (I haven't found any yet


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