Jesse Livingston Rocking Valve Mill Engine

[Jasonb]

I was thinking teh same the other day, hope this is progressing unseen.

I have got quite a bit of this drawn out in metric though I have deviated from the Livingstone design and gone more towards the Filber and Stowell rocking valve saw mill engines.

I do know that Ramon has not been in the workshop so doubt his one has progressed

[Jim Nic]

I'd be very interested in your drawings if you get round to completing them Jason.  I'm keen on the rocker valve set up rather than Jesse Livingston's design for it's own sake and a clear set of drawings would be rather better than what I have now.  Having built your Jowitt I think this would be a popular with others too if you made them generally available.  (Not that I'm pushing, you understand)

However, it would still be good to know how Todd is getting on.

Jim

[tinglett]

Hi all...and yes I am still here!

This engine has taken a bit of a hiatus as I finished a couple woodworking projects as well as the following little distraction....





Nichols and Shepard gets credit for building it in 1923.   It's a 20hp and hopefully will be running in about a week.   Then I'll get back to the regularly scheduled program .   This rocking valve engine has sat neatly on my bench.  I plan to make the cylinder covers next and ideally will keep up a reasonable pace to keep everyone's interest.

On the plus side, no build log or photos have been missed!

Todd

[crueby]

Wow - thats a nice little toy!   

[b.lindsey]

Yeah...that would distract me too Todd!!  Hope we get to see it running as well.

Bill

[crueby]

Yeah...that would distract me too Todd!!  Hope we get to see it running as well.

Bill

Yeah, I'm in Rochester too, drive it over!!!  Oh, wait, one of the OTHER Rochesters.... Rats!

[Jim Nic]

Umm, yes.  I can see that one of those could take a man's thoughts off a model.    Thanks for keeping us informed and good luck with the "biggie".
Jim

[tinglett]

Cylinder Heads


Well, it's still steam season so I'll be distracted for a handful more weeks, but I did manage to get my shop back in order and knock out a couple of simple parts.  This time it's the cylinder heads.

The heads are suppose to match the diameter of the cylinder, but I thought I'd make them a bit proud of the surface on the chance that might look a little better.  Until I solder on the valve chest, I can chuck the cylinder with head and turn it down for a perfect fit if I change my mind.  Here I started on the front cylinder head, part C10, turning out a 1 inch boss that fits the cylinder bore.



I sliced it off with the bandsaw and had to face the back side.  Since the boss was 1 inch I could chuck it in a collet.  Very light cuts and no mishaps.  I suppose I should learn the trick of gluing it to a flat surface for these cases.



Finally I did a light trepanning operation on the front.  This was purely cosmetic and I went deep enough until I thought it looked good.   My depth was 15 thousandths and I see the print called for 31 thousandths.



Before drilling the bolt circles, I made the rear cylinder head, part C11, in a similar manner.  This part has a boss on each side.  The smaller diameter boss, but more protruding, fits the crosshead trunk and is 0.75 inch.   The larger diameter, but shallow, end fits the cylinder and is, of course, 1 inch like the front cylinder head.





Finally, the rear cylinder head had to be drilled and reamed to fit the piston rod.



I still need to thread the cross-head side of the rear head for the packing nut.   This is a 3/16-24 thread and I don't happen to have a tap for it.  It's an excuse to fill out my tap collection so I'll do that later.

Next it was a matter of drilling bolt circles to match the cylinder.   The front of the cylinder has a full circle (shown), while the back had a different layout due to the construction of the cross-head.



Finally, I decided the heads were a little too big so I trimmed back the diameter on the lathe.  This was easy because I could bolt them in place for the cut.   I did this by eye and matched the rear cylinder head to the same diameter.



Not too shabby!  The engine looks much better with the heads in place.



Sorry for so many pictures for so little work, but I have to make it look like I'm working somehow!   Hopefully this build will speed up in the next few weeks.

Todd

[Ye-Ole Steam Dude]

Beautiful work Todd, and I like the slightly over size heads.

Thomas

[b.lindsey]

Nice looking build so far Todd. Hope you can get back to it soon.

Bill

[tinglett]

Valve Chamber and Exhaust Port


I finally got back into the shop for some metalworking!  This weekend I made the valve chamber and exhaust port, both of which were a bit taxing for me as I haven't been doing this for some time and what little skills I have are already a bit rusty.

I started with a 1.25" sq bar of brass to form the valve chamber.  The valve chamber straddles the cylinder and needs a cove cut which I made with a boring head.  I haven't used this boring head much and figuring out how to adjust for the proper diameter was the first puzzle.  Since this part needed to be cut to fit the cylinder, I decided that "close" was good enough so I simply centered the mill over the edge of the stock using a center finder, moved X out to the 0.75" radius, installed the boring head and finally adjusted the bar to just nick the part.  This worked fine, but when testing I found the cut was slightly undersized.  But with a few more cuts I finally got a nice fit.



I used a stop as you could see in the previous photo.  While this may have helped hold the part for the boring bar, I really used it for the next operation which involved drilling a hole for the rotary valve in the side of the part.  I touched off zero on the curve as the part was placed in the previous photo, then flipped it sideways and dialed it back in X to where this hole needs to be.   Note that I also made some layout markings just to keep my head on straight.  As I did this, I ran into another puzzle.  I had carefully machined this block of brass per the prints, but found that the block was much too high (in X in this photo).   The error in the print is that it is dimensioned as 1-3/16ths, but it is really only 13/16ths.  Why fractions are used in the first place is beyond me.  The funny thing is that the photo in the book shows the same mistake.  The part looks exactly like mine .



While my boring head was set for the cylinder radius, I set the valve chamber aside and worked on the exhaust port which also mounts to the cylinder.  The port is 11/16ths diameter (yes, fractions!) with a 1/4" hole for exhaust.  I turned and drilled it using my spiffy 5C collet chuck which I got from Santa last year .



And then it was back to the mill to machine the curve to fit the cylinder.  This time the stop was really just helping hold the part.  The stop was still in place so I used it.



Fitting the exhaust port to the cylinder turned out to be much more fiddly than I thought.  There will be a valve cover on the valve that may interfere with the exhaust port.  In the next photo you can imagine a valve cover in the valve chamber in the block I machined earlier and you can see how it may interfere.  I took the exhaust port back over to the mill to "raise" the bore a little higher (with respect to this photo), and eventually just turned the port to a bit smaller diameter to finish it off.   (By the way, it was incredibly fun to hold the parts and camera and push the button at the same time for this photo!)



Next I had to cut ports through the valve chamber.  And here is where I hit puzzle #3.  In looking at the spacing of the parts in the valve chamber, I realized they didn't match the cylinder ports!  Perhaps it was a good thing the print had a publication error in the dimension of the overall valve chamber size because I was now looking at dimensions like a hawk and probably would have overlooked this.  Looking at the part in the next photo you can see the lines I scribed for the ports.  The center is exhaust and, of course, lines up perfectly.  The two side ports are dimensioned as 3/32 away from the center port's edge for the valve chamber, yet they are 5/32 away on the cylinder.  Yikes!  It could be that the publisher misread a 3 for a 5, or maybe the original drawing had the spacing from the centerline.  I decided the valve chamber must be correct as the total overall distance between outer edges matched the valve chamber hole.  So I decided to cut the valve chamber per the print:





Then I went back to the cylinder and knocked off the inside edges of the ports at a 45 degree angle to form steam passages.



Next I flipped the valve chamber so it was oriented as it will sit on the cylinder and drilled an input passage straight down.  Note that I had used a bandsaw to finally trim off the excess material off the top.



Finally, a little RT work allowed me to cut the angles and round off the top.





And here we have two new parts, along with a slightly modified cylinder.  I think everything is going to line up now.



Next I need to machine a steam inlet cap that sits on top of the valve chamber.  This inline cap will serve as a flat mounting spot for the governor.  I also need to make a valve sleeve.  You may have wondered why I simply drilled the valve chamber rather than reaming for a valve, and this is because it is sleeved.  I was wondering why the heck it should have a sleeve, but I think it's because the sleeve can have much more precise slots cut as they can be cut straight into the sleeve rather than at goofy angles as I have inside the valve chamber.  But that's next time.

Thanks for looking!

Todd

[crueby]

Good to see you back at this one - some complex parts, very well done!!

 

[Flyboy Jim]

Good write-up and pictures.  That's an impressive part!

Jim

[b.lindsey]

Great to see more progress on this one Todd.

Bill

[tinglett]

The Steam Inlet and Soldering it Together


[Edit Dec 17...fix the photo urls]

Today the project goal was to make the steam inlet which sits on top of the rotary valve chamber, and then solder these bits together.

The steam inlet was pretty simple.   The valve chamber had to have its base machined as a curve to fit the cylinder in the last post, and this part was similar in that it needs to sit on the curved top of the valve chamber.   I made the valve chamber with an 11/32" radius per the plan, so this was a matter of starting with brass rod and using the boring bar to machine a match.



This was straightforward since I had done the similar operation a few days ago.  The bit of rod I had was oversize, so I took it to the lathe to turn it down to 11/16" as called for by the print.  Now this diameter is purely cosmetic, but I turned it accurately so I could use it in a collet to work the other end.



Here I've flipped the steam inlet around and put in a smaller collet and have already parted it off slightly overly long.  I thought it best to drill the 1/4" steam port from this end so I didn't have to deal with a curve causing centering issues.



Here's what the steam inlet looks like sitting on top of the valve chamber.



Here's my soldering setup.   I had to fiddle with the exhaust port which is being braced against the side of the cylinder with an old machinist's square.



I squashed some bits of solder to fit along the inner surfaces under the valve chamber so these spaces would seal up.  I figured that if I fed gobs of solder in there to do this, I'd most likely seal up all the ports.



Ok, my soldering skills aren't so hot  ... but it all stuck together good.  I used Stay-Brite soft solder for this job.  I was having trouble with the steam inlet port and perhaps overheated the flux.  You can see a gap that looks bigger than it was.  I decided to stop messing with it and resort to JB Weld for sealing up any remaining bits which turned out to be only in the inlet and outlet, but not in the valve chamber itself.



And finally, here it is after a little bit of cleanup.   Everything stayed aligned pretty well, except the steam inlet tilted ever so slightly to the back of the cylinder (which is in view in this photo).  I had left about 0.050" extra material on top, so I'll skim it off to level it perfectly when I drill the bolt holes for the governor. 



Thankfully, the ports all seem to have remained open.  Hopefully they sealed up between each other, and I'll attempt to test them once I've made the valve.   Next up, after cleaning up my messy solder job, will be the making of the valve sleeve and then the valve itself.  Then I'll put more bits back together and get a full family shot out here.

Todd