Tandem Compound Poppet Valve Steam Engine Build, ala Cedge

[Brass_Machine]

 


That is all!

Eric


oh yeah!  <---- that too

[cedge]

Thanks everyone.

I'm taking my time, trying to get it right as I go along. The window technique itself is not my original idea, if I've given that mistaken impression. There is a German fellow who built a pair of engines, similar to these, and put up a build log on his web site. I've poached a number of his ideas even as I've added some of my own. That only seemed fair since he's poached one of my best animations for use as a signature image on his site.

Steve

[cedge]

I didn't get a lot done today, but what was accomplished tied up a few loose ends that were bugging me. The windows on the cross head guide are now filed and rounded to their final size and shape. They turned out to be a somewhat delicate feature that added a nice bit to flair the project. The second engine's guide will begin tomorrow and I'm hoping it will turn out even better than this one.


http://cedesign.net/steam/images/misc/multi-valve/build/guide-13.jpg

The rest of the progress was limited to getting the gland nuts made and fitted to the glands. These were turned from a 1/2 inch piece of hex brass that made it easy to make.... you got it.... hex nuts....(grin)


http://cedesign.net/steam/images/misc/multi-valve/build/gland-2.jpg

You'll notice the gland nuts are flat on the thread ends. When I drilled the holes to thread the gland body, I left the taper the end of the drill bit created. The flats will press the packing into the taper and against the piston rod as the gland nut is tightened. Since I used a 3/8 x 32 TPI this arrangement will allow me very fine adjustment to control how snug the packing is compressed. the nuts were drilled .010 over the size of the 3/16 piston rod. Since the gland was reamed to size, it will hold the rod concentric, negating the need to add additional friction points in the nuts.



http://cedesign.net/steam/images/misc/multi-valve/build/gland-1.jpg

Here are the two gland nuts were what had me a little worried about the length of the original spacer between the cylinders. They even added something to look at through the small windows. Looks like I'll need to center them up a bit before I'm done.



http://cedesign.net/steam/images/misc/multi-valve/build/gland-3.jpg

The strange silver looking string is the graphite impregnated material Zeusrekining shared with me during the Water Pressure Engine project. This stuff makes perfect stuffing for the glands and acts as a lubricant was well. It remains low friction even after it has seated and worn in. It's available from McMaster Carr as well as Smallparts.com.


http://cedesign.net/steam/images/misc/multi-valve/build/gland-4.jpg

Here are the pieces all fitted up and awaiting the stuffing.... among other things....(grin)


http://cedesign.net/steam/images/misc/multi-valve/build/gland-5.jpg

Steve

[MikeA]

Hi Steve,

As usual, I'm just catching up with this build and you continue to impress with both the quality of work and even more so, the ingenuity demonstrated in some of the procedures you use - almost makes it look easy!

Can hardly wait for the final product a la Cedge.

Best,
Mike

[cedge]

Bob
Thanks for the tip. I typically deburr holes with a countersink, which leaves a taper in the end of the hole.... so I guess I do add a bevel in the nut without really thinking about it. See what I mean by habitual things are difficult to document?

I'm trying to keep these two engines fairly close to the same level of completion, as I go along. That means that I have to consciously stop and assess what is falling behind on one or the other as I work my way through test fits and such. Today I managed to bring both engines to the same place and got a lot of small things accomplished.

The second crosshead guide is almost done, needing only a bit of hand work on the window and some cleaning and polish. It was a little tricker to make since the bead on the end of the cylinder was intentionally cut smaller than the rest of the ends by a full 1/8 inch. Lucky for me my calculations were right on and I didn't have to change the hole pattern to make it work.

While the engines are of the same basic design, I've decided to give them different details. The single cylinder version will have the piston rod exposed on both ends just to give it a bit more motion when running. The tandem engine now has a longer crosshead window which will hopefully allow me to use a novel oiler system. Other small  things will receive cosmetic differences as things progress.

Here are the two engines as they sit a the moment. Sorry, but the things I accomplished over the past couple of days were simply repeats of things in previous posts. No one wants to see photos of all of the nearly 150 small holes the project has required so far....LOL

[shoey51]

  im still trying to work out how it works but I guess ill have to wait till the end of the thread

  lovely workmanship as always

[madjackghengis]

As I work to move my own project engine forward, with my best efforts barely maintaining the level of accuracy necessary, making parts two and three times sometimes, I watch in awe as Cedge off-handly it would seem, produces flourishes and curves on all his work, while seemingly effortlessly getting the accuracy necessary for a working engine.  I was in awe, reading through the build log for the "Cedge's Victorian engine", and watching it come out, a veritable work of art.  This build now will surely be another pair which meet that standard.  Look up "craftsman" in the dictionary, and Cedge's picture is right there, I swear it is mad jack

[cedge]

Jack
You're a silver tongued devil for sure....LOL. I'm not doing anything miraculous. I just don't share photos of my "extra" parts...(grin). Truth being told, I've made "extra" glands (2 ea) , spacers (2 ea) and cross head guides along the way (3 ea) . I'm also sure there will be more extra parts before this project is done.

I didn't really get comfortable with my machines until the Victorian project was under way. Somewhere in the early stages of the project,  I quit sweating over "process" and began to do it "my way". The whole project then became a lot of fun instead of being frustrating. I've come to believe that if you can visualize it, there has to be a way to build it. Others seem to manage these things long before I came along... I just had to figure out how they did it from the clues they left.

Take your time and think through the "process" before you attack metal. Once you've made the part in your head a few times, the machines tend to listen to you much better. I'm also fearless when it comes to asking questions or seeking advice. If it makes me feel like a dummy, it only hurts for a few minutes and then I'm not the dummy anymore. The only other tip is to stop listening when someone says "that won't work" or "you can't do that". as long as you don't know you can't.... you probably can.  Oh yeah... one other major tip... always wash your hands before you go pee.

Steve

PS.... the guy in the dictionary is a doppleganger....LOL  I'm listed under Studly Male

[madjackghengis]

Cedge, the truth is, I was a child, living in Europe as a Navy brat for my first five or so years, my mom felt it would be a criminal waste to be where history was, and not experience it live, so my sisters and I went everywhere you can go by bus, carrying sandwiches and water, and we saw all the ruins of Greece and Rome, as well as Venice and Barcelona, and I look at your engine work, knowing well the special features are artful flourishes, and they make your engine work personal, it carries your own mark, and were you building full size engines to do what a city needed to be done, yours would be recognizable, as, I would dare say, would most other craftsmen's, and we all leave our own mark in our own way.  I spent a lifetime working to a standard with the military being a large part of it, and am only starting to enjoy adding those "flourishes" in the past decade or so.  It has caused a new appreciation for the use of oxy-acetalyne, silver solder and brazing, as means of giving form to cold sharp corners and the like.  This forum is almost like being able to hang out with like minded people that I have wanted so long, but never experienced.  I'm following about six or seven builds, and getting a lot of ideas and inspiration from them.  It's good, because I've got lots of projects going, and need to get more finished.  You do a great job explicating your process and your purpose, and you make it all look easy.  I'm really looking forward to video of two engines running.  mad jack

[cedge]

The engines in this project are what are known as side rod style. This means there are cams on an independent shaft which runs down the side of the machine, rather than the more familiar steam chest / D valve system. It also means there has to be something to support the shaft and I've got to make them.

I've studied a quite number of photos of these little machines around the web and there are generally two ways to mount them. Some use the head bolts on the cylinders while others bolt up or are riveted to the exterior wall of the cylinder. After some consideration, I chose to go the latter route on at least one of these engines.

While I've been doing all that drilling, I've also been working through how to best duplicate some of the repetitive parts this project will require. It finally struck me, while running my pirated Crap O' Cad that there might be a simple way to do things. A simple sketch was undertaken and what began as a single arm drawing, soon became four. 


http://cedesign.net/steam/images/misc/multi-valve/build/arm-1.jpg

Once the brass was squared, the lay out was made using a center drill to locate the holes. I removed the moving jaw on my Phase II vice and bolted back on the end of the sliding body and clamped in a piece of scrap yard aluminum tooling plate I had laying on the shelf. This too was drilled at the center point and another hole was added to match the radius of the outer holes. The would become the pivot and locking points during the milling process. 

The metal strip you see is a piece of 0.01 inch shim stock that I use for locating the end mill. Run the end mill down until it just begins to "scratch" at the shim. You are now 0.01 inches above the work piece. Set your Z dial or DRO to zero, run it down an additional 0.01 and you are exactly at the surface level of your work. Reset the dial or DRO to zero once more and you're ready to go to work. The reason for doing the Zero thing twice is so if you miss the mark on the way to the surface, you have a place to begin again without going through the whole procedure.


http://cedesign.net/steam/images/misc/multi-valve/build/arm-2.jpg

Before we go any further, a small warning is in order. This is a hand controlled operation and requires you to work in relatively close proximity to a small very sharp cutting tool that cares not one whit if it is chewing on metal..... or on you. Awareness of where your hands and fingers are at all times is not to be taken lightly, even for a moment. If you aren't comfortable with the idea, please do not try it. You will do so at your own risk. It's a process that requires very small diameter tools (no larger than 3/16 here) and very light cuts. You'll also want to avoid making climbing cuts as if they were the plague. Climbing cuts WILL run away on you and do damage to the work piece and quite possibly..... YOU. DON'T DO IT!!.

Once the tooling/ jig and such were complete the first cuts were made. As you can see, center pivot for center cuts, outer holes were the pivot points for their own radii. Since the dowel pins allow easy repositioning of the part, it's a fairly quick procedure to rotate or flip the work piece. Both sides were given the same treatment to create a mirrored effect. One quick note..... The final finished depth of cut on this part will be .0625. At this stage of things, I'm only cutting own to about 0.040. This gives me a chance to correct mistakes as well as play a bit with a couple of visual ideas that might become part of the final version. Thus the reason for the ball end cuts.


http://cedesign.net/steam/images/misc/multi-valve/build/arm-3.jpg

The phioto below shows the reason for the holes drilled at the 45° points. They are the pivots for the long cuts from one arm to the other, as well as for cutting the openings I'll soon add to the arms. Still not working to final dimension on any front. the Z is still at 0.040 and I'm working 0.020 from any of the final side cuts. If I screw up, I'm still going to be able to fix quite a lot of stupid...(grin)


http://cedesign.net/steam/images/misc/multi-valve/build/arm-10.jpg

Once I had a good visual grasp, I began to work toward the final design. The arms were freed along the long arcs, but the ends were left attached. The excess metal was removed along the edges as well as the surfaces. I'm still working above the final dimensions but things are moving quickly to the point where the final elevation and side cuts will be made. Both sides of the work piece are still getting identical cuts, so there is a lot of relocation happening between photos.


http://cedesign.net/steam/images/misc/multi-valve/build/arm-4.jpg


http://cedesign.net/steam/images/misc/multi-valve/build/arm-4.jpg

Here the final elevation was finally cut, leaving a thickness of 0.125 inches. Plenty to work with when it comes time to do the hand filing. The webs will be opened, so I've center drilled the ends of the opening with a #30 drill, which is just slightly larger than the 1/8 inch end mill I'm using. This will let me center the mill as well as giving me just a tiny bit of room to exit the cuts without crashing into metal I want to keep.


http://cedesign.net/steam/images/misc/multi-valve/build/arm-5.jpg

Here, the small openings are being cut in the web of the arms. These engines have a rather delicate appearnce when they are completed, so I'm avoiding having large flat areas for both the delicacy idea as well as being able to see through the parts.

Something not quite obvious.... The initial idea was to leave the inner "rim" intact and square the ends.  I began cutting and realized the cuts would be easier to make as a single arc, if I let the cutter run through the edge of the rim. Instead of a squared edge, the bases of the arms would flow right into the cylinder walls for a nice clean effect. I watch for small changes like this to add a bit of flourish. It also made the final separation much easier, since a single cut around the inner rim would free all four arms.


http://cedesign.net/steam/images/misc/multi-valve/build/arm-6.jpg

All cuts have now been made to final dimension. No fresh metal to work with if I screw up now, it'll take luck and hard work to correct things if anything goes pear shaped. The piece has been cleaned up a bit with fresh ball cuts to blend the corners and shape the ends of the arms. The final arm is waiting to be released from the spare metal and all is well. Here is a good time to make even lighter cuts than normal, just so the end mill doesn't get that last nasty bite at your work.


http://cedesign.net/steam/images/misc/multi-valve/build/arm-7.jpg

The part is now free of the original metal. I've heard it said that there is a part hiding within each piece of metal. All we have to do is remove everything that is not part and we get to liberate the part. You've just made that journey with me. My wife wandered through as I was making this photo and I almost lost the part to her. She now wants me to duplicate this stage of things in stainless steel so she can have one to wear on a chain. The hazards of metal machining are not all blood and stitches.....LOL


http://cedesign.net/steam/images/misc/multi-valve/build/arm-8.jpg

Here are the final parts, awaiting my hand and a small file. They are not nearly as rough as the camera makes them look. Between the sharp focus of the camera and the harsh light of my shop, the small machine nmarks look like the are of Grand Canyon scale. A little work with the needle files and these puppies will be ready to bolt to the tandem engine. Now if I can only come up with something a little different for the single cylinder.


http://cedesign.net/steam/images/misc/multi-valve/build/arm-9.jpg

Steve

[Bernd]

     


Bernd

[dsquire]

Cedge

A+++ and go to the head of the class. 

Cheers 

Don

[Stilldrillin]

 

 

 

David D

[madjackghengis]

Cedge, that is beautiful work, I just have to wonder if your wife has any idea of the difference there is between machining brass or bronze, and machining stainless.  I found your method of setting the "touch off" of the end mill interesting, I was taught to use a cigarette paper, and bring the cutter to just hold the paper, and move the cutter till the paper moves with slight friction, and having exactly a thousandth after that.  The old guys in the shop said it was too easy to put pressure on a feeler gauge and not know it, but impossible with the paper.  Obviously you haven't let it interfere with your skills, just a curious difference in experience.  I think you are making the project art, by ensuring all that open space, and all the visibility.  It makes a world of difference, even if it does impact a bit on the time it takes.  I end up working with stainless on a regular basis, and some of them will literally reach out and grab a chunk of flesh and rip it out of your hand while you are being dutifully careful.  I can't wait for the video of the first engine, or for that matter, the second one either.    mad jack

[cedge]

Jack...
I'm smarter than that. I put her on the list of "to do's" and then I'll let time take its toll on her memory.  It'll still be there on the list but it isn't going to move very much. If her memory doesn't fade quickly, I can show always her it's still there....... when I get to it. .....LOL.  A wise friend told me that his shop existed only to keep him entertained and occupied until he's called to a higher place. I had to agree with his definition. Time has no real meaning in such a place, so if it takes 1 minute or 12 hours, it's just what it takes to get it right.

I've used the paper trick as well, but the shim stock is just easier to keep right there on the machine. It has a small nest just above the quill's fine movement dial. I've never really noticed any problems with it, but I work by feel. The minute can feel the end mill scratching the metal, I reset the DRO. Since the scratching doesn't leave any visual mark, I figure it's somewhere around .0001 - .0002 plus, or minus. I might use that level of tolerance for marking out, but would need a much more rigid machine to actually mill in that nether region.

I finally found something that will produce a nastier ribbon than stainless. I recently played with a marine grade of cupro-nickel which is still in the bronze family. Wicked stuff. If it isn't making razor spirals of death, it yields millions of microscopic needles that can penetrate nearly any substance known to man. I'm eventually going to use it for an engine project, but I'm not in a hurry.....LOL  The stuff makes 304 stainless look user friendly.

Steve

[Divided he ad]

Well, I thought you were going to produce something stunning, special and innovative Steve.....






Holy 5417!!!     It seams I was correct 



Gotta love the way the mind figures all this stuff out ehh?   




Most impressed/dumbfounded/flabbergasted    ( take your pick...   )








Ralph.

[cedge]

Thanks Ralph.... I'll choose flabbergasted..... LOL

I spent today sitting on the back deck in the sun with a small file and four small pieces of brass in hand. I decided to take it easy, after having broken a rib (the short floating one at the bottom of the left rib cage) over the weekend.  Standing in front of the mill just didn't have a lot of appeal for, some reason. I did manage to get most of the tool marks removed as I hand shaped the pieces. Unfortunately, this turn of events is likely to slow my progress for a few days. I'll get to a few minor items, but I'm going to give the next push some delay to let some of the soreness diminish.  Anyway.... here is what the pieces look like with a bit of hand work and a spot of polish. they'll still need a minor modification to the bases, but they do fit nicely.


http://cedesign.net/steam/images/misc/multi-valve/build/arm-11.jpg

Steve



 

[Bernd]

Amasing what a back porch and bit of sunlight can produce.

A can or bottle of your favorite beverage would have gone along nicely with that filing job and may have helped alleviate the pain a bit. 

Bernd

[cedge]

Bernd....
Trust me.... the favored beverage idea was a serious consideration later in the day. If I hadn't been removing very tiny spots of metal by then, I just might have succumbed to the temptation. No telling what I'd have had to correct tomorrow....LOL

Steve

[madjackghengis]

Jack...
I'm smarter than that. I put her on the list of "to do's" and then I'll let time take its toll on her memory.  It'll still be there on the list but it isn't going to move very much. If her memory doesn't fade quickly, I can show always her it's still there....... when I get to it. .....LOL.  A wise friend told me that his shop existed only to keep him entertained and occupied until he's called to a higher place. I had to agree with his definition. Time has no real meaning in such a place, so if it takes 1 minute or 12 hours, it's just what it takes to get it right.

I've used the paper trick as well, but the shim stock is just easier to keep right there on the machine. It has a small nest just above the quill's fine movement dial. I've never really noticed any problems with it, but I work by feel. The minute can feel the end mill scratching the metal, I reset the DRO. Since the scratching doesn't leave any visual mark, I figure it's somewhere around .0001 - .0002 plus, or minus. I might use that level of tolerance for marking out, but would need a much more rigid machine to actually mill in that nether region.

I finally found something that will produce a nastier ribbon than stainless. I recently played with a marine grade of cupro-nickel which is still in the bronze family. Wicked stuff. If it isn't making razor spirals of death, it yields millions of microscopic needles that can penetrate nearly any substance known to man. I'm eventually going to use it for an engine project, but I'm not in a hurry.....LOL  The stuff makes 304 stainless look user friendly.

Steve

I figured you'd had the experience and just chose the other way, for those with a keen sense of touch it doesn't really matter, it's the attention that does the trick.  I've run into that cupro-nickel you're talking about, the last machine shop I worked in specialized in boat shafts, repairing, straightening, and replacing with new, and I have to agree, that stuff makes stainless child's play.  That is a fine looking pair of stanchions you've got filed and sitting on the cylinder, they fit the image of the rest of the work right nicely.  That rib thing will go away before you know it, and you'll be standing in front of the mill in no time.  Damn shame a bit of silver solder won't fix such things so easily.  I'm looking forward to seeing it either standing up, or laying down, with a con rod and a crank attached.  mad jack

[cedge]

Jack....
The rib thing was not on my to do list and it's annoying me somewhat to not have the stands underway. The silver solder wasn't an option on another front. I've got to turn the round stubs down in the next few moves, but they are going to be needed to locate the stanchions properly.  With the stanchions being permanently mounted the stubs can't be turned down.  One of those chicken and egg moments.

It's not too far from the con rod and crank fitting. Once I've got everything mounted on stands, I can work from elevation to fit them. Then it'll be time to begin the valve work and such. I'll have to admit the project has moved along more quickly than expected.... especially when compared to the Victorian engine. Those items will slow things down a bit. I've refused to set any deadlines for completing these, so I'm not working under the gun, as I was last season. Thank the gods, this project shouldn't require all the spastic gyrations the little IC engine needed at start up.

Steve 

[Baldrocker]

Cedge
The problem with this post is I have to immediately rush to the
shed and try the thecniques you show, leading to many late late
nights, seriously p!@#ng off SHMBOO. Please please keep going.
br

[cedge]

Roger BR... we'll try to keep her fully p*ssed off for the duration....LOL. Now then.... what are you going to do with your 4 little stanchions?....(grin)

Steve

[madjackghengis]

Jack....
The rib thing was not on my to do list and it's annoying me somewhat to not have the stands underway. The silver solder wasn't an option on another front. I've got to turn the round stubs down in the next few moves, but they are going to be needed to locate the stanchions properly.  With the stanchions being permanently mounted the stubs can't be turned down.  One of those chicken and egg moments.

It's not too far from the con rod and crank fitting. Once I've got everything mounted on stands, I can work from elevation to fit them. Then it'll be time to begin the valve work and such. I'll have to admit the project has moved along more quickly than expected.... especially when compared to the Victorian engine. Those items will slow things down a bit. I've refused to set any deadlines for completing these, so I'm not working under the gun, as I was last season. Thank the gods, this project shouldn't require all the spastic gyrations the little IC engine needed at start up.

Steve 

Steve, I wasn't suggesting the silver solder for the stanchions, but for the rib   I know you've got to get everything lined up before you can use it on the engine.  I made it through my first year I can remember without breaking a bone last year, after I made a resolution, which happened right after I broke four or five bones in my foot, a few fingers, and a rib all in one year.  Of course a month after I'd made it a year, I broke another finger, so things are back to normal, if still breaking bones is normal after fifty. mad jack

[zeusrekning]

Steve, beautiful work. It is truly a shame we never had you in the manufacturing industry.

I do have to give the modders here some insider info; when I visit Steve's shop there are many "extra" parts laying around. Possibly a misplaced hole or even a change of artistic design. But I've yet to see a part stuck in the wall. In my opinion he does very well at learning from his mistakes and not letting it get to him. I think that is the biggest hurdle for most of us. If I make a bad part, I continue to hold onto that and let it burden me moving forward.

Again, awesome work man.
 


Tim