Four Valve Non-Releasing Steam Engine

[b.lindsey]

Wow Jerry, you got a lot done in a short amount of time and it looks fantastic. Will definitely be following along...this will make a fine model indeed!!!

Bill

[Jo]

Great start

Is that a 2" long cyclinder I spy on your drawing? Are you intending on posting your drawings as you go along so that we can follow you on your journey?

Jo

[Jo]

Guys,

I still have not worked out how to view pdf's from google ..... but I  found a very good extract from the book here:

http://www.wkinsler.com/technology/corliss/index.html

And some really good diagrams from the book:  http://www.wkinsler.com/technology/corliss/figures/index.html



Jo

[NickG]

Jerry, I agree, I think it'd look best with at least a 5" Flywheel. Nice work ...

Nick

[Captain Jerry]

Thanks for all of the replies.

The family continues to grow.  A wedding in Nov (grandson #4) will bring a new granddaughter-in-law.  Another wedding to follow shortly (grandson #1) will add another granddaughter-in-law if she answers the proposal affirmatively.

As to project progress, I have decided to postpone the arduous task or drilling and tapping in favor of making big pieces.  I may just glue them all together.  I may have mentioned previously my unrealistic fear of fasteners.

The next big piece is the crankcase and bearing stand.  I have not yet decided how I will handle the large radius curve on his piece.  I am thinking of using a hole saw followed by a boring head or flycutter to finished size.

Yes, Jo. That is a cylinder drawing under the pieces.  I have not posted drawings in the past for two reasons.  I have no training in proper drawing and dimension positioning.  I tend to produce working drawings from the 3D model with detail limited to the procedure at hand rather than a complete drawing with all detail and dimensions.  Here is an example of what I took to the shop for the general development of the cylinder.  Note that there are no bolt patterns and that some useful dimensions may need to be derived.

If I don't get to many complaints about this style, I will try to provide more examples.


If this drawing does not display, it may be a problem with Photobucket.  I have been fooling with it for over an hour with unreliable results. I will work on it tonight



If anyone wants more specific information that is shown, just ask.

That link that you posted is indeed a wealth of information.  It was previously posted by Arnold in the previous thread and I spent some late night hours with it.  It is at the top of my bookmark list and referred to often.

Thanks for watching.  Stay tuned. More to follow.

Jerry

[steamer]

I can see the pictures just fine Jerry....

Dave

[Captain Jerry]

I set out today to make this:



I was not sure how I was going to go about it.  I had already decided to make it in three pieces, front plate, bearing support, and base channel, and JB them together as one.  Milling the deep wide slot it the base channel was just a lot of heavy milling with a 3/8" end mill.  The question was how I would go about the large radius.  While I was thinking about it, I decided to change the design.  The Tangye style has two different radii.  This provides more support for the bearing support with a higher wall section on the bearing side and good access to the crank with an open side, so this is what it wound up with:





The sweeping curve was no problem at all.  I used a boring head in the X2 mill.  I set the radius of the cutter by eye.  The dimension is not critical.  With the part clamped in the vise, the spindle was centered appropriate bore center and the X an Y indicators zeroed.  Then I backed of in the Y axis until the boring too just touched the edge of the part.  I then made repeated cuts, rasing and lowering in the Z axis, moving the table in the Y in increments of about .030" per cut.  When the Y indicator reached Zero again, the boring head was replaced with an endmill and the long edge milled tangent to the curve.  The small radius was done in much the same way except that I used a 3/4" S&D drill bit instead of the boring head. 











I still need to profile the top edge of the front plate and work out the details of the bearing support. 

Stay tuned. More for tomorrow.

Jerry

[metalmad]

Looking very ship shape Captain
Pete

[swilliams]

Hey Jerry, I appreciate your drawings, they show what's going on just fine and really help with following what you're up to. I hope you keep posting them!

Steve

[gbritnell]

Hi Jerry,
It's coming along nicely and you're making quick progress. Rather than use JB weld (although I know it's good stuff) I would try to put some small screws in a few spots just for the added strength. They could be countersunk or counterbored a touch deeper and then filled with JB to give a casting look.
gbritnell

[KB]

Great strides Jerry!

I am always happy to see you "thinking" about an engine design, because I know it won't be long until it comes to reality. And here it is!

[Captain Jerry]

I took a few days off to do some other stuff but I got back to it yesterday.  I didn't have time to post anything last night but this is what I got done.



The bearing stand is worked out along with the cap.  I decided to go with a cast iron bushing instead of oilite or split brass.  It may not be proper but I have found that it gives very good performance and wear.  I have not bonded the three pieces of the crankcase together yet.  They will be screwed and glued as per George's suggestion above, thanks George.  I decided not to fix the position of the bearing stand on the base until I had worked out the lengths of the piston rod/conrod combination and I think I will make the crankshaft first as well.

Yesterday, I also worked out the piston, rod, and crosshead.

Piston - Cast iron:



Head - Rod end - Cast iron



Packing gland nut - Brass



Con Rod Fork End - Cast Iron



Everything except the crank end:



That's it for today, more tomorrow.

Jerry

[zeeprogrammer]

I'm really liking this engine Jerry. Nice work!

[cfellows]

Guess I've been too busy in the shop to notice this thread.  The Corliss engine has always been one of my favorite designs.  Yours looks like a particularly handsome example.  Very nice work, with work being the operative word!

Chuck

[Captain Jerry]

Chuck

Thanks for tuning in.  I understand that you have a few things going on in your shop as well.   This engine style has always appealed to me because it is so clearly obvious what it is to anyone who has an interest in steam engines.  BUT!! there is a lot of it that is not really very different from any other steam engine.  It has a piston moving in a cylinder, guided by a cross head in a guide with connecting rod turning a crank and a flywheel.   The only thing that is really different is the valve mechanism, and there is a whole lot of difference there.  I am going to take the simplest possible approach to this, hoping to create a working 4-valve mechanism driven by a single eccentric through a wrist plate mechanism.   

If it works out, and if I learn anything useful, this will be the first of a series.  There are many refinements that could be added but first, the basics.  Cylinder, piston, cross head, con rod, crank, flywheel.  I am almost there, but not quite yet.  Here the frame is bolted together and I am about ready to decide on a base plate so that I can setup the outboard bearing stand.  After that, I will get the pieces working smoothly before tackling the valves.




For those that see the Socket Head Cap Screws and cringe,  they are only a convenience for the anticipated assemble/tear down/assemble cycle to follow.  I intend to go to studs and nuts on final ( ) assembly.