Building Kozo's New Shay locomotive

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Fine work, that has to be really satisfying to see it run. I sure hope you decide to come to Cabin Fever with it.

I've been considering it, but there is still so much not done on it before I can run it on the loco itself. Next year for sure!
 
WOOHOO!!! Outstanding!! :) Congrats on another milestone. She really sounds good. I can hear she's a bit lopy at low speed which is what you describe. Probably just some minor timing adjustments. But, at the higher speed she sounds great. Good Show!

Todd
 
WOOHOO!!! Outstanding!! :) Congrats on another milestone. She really sounds good. I can hear she's a bit lopy at low speed which is what you describe. Probably just some minor timing adjustments. But, at the higher speed she sounds great. Good Show!

Todd

Thanks! I figured out why my face was hurting - all that grinning!
 
Well, in between running the engine more times, got a start on the rest of the reverse gear linkage. The hangers are brass bearings that bolt to the front of the piston rod guide columns and hold the rod that connects all the reverse gear link arms. They started out a length of brass bar, and drilled/reamed holes for three hangers down its length.
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Next step was to drill the mount holes, measured off the centers of the bearing holes.
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Then flipped it over and milled out the bearing shapes in the tops.
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After cutting them apart and beveling over the corners of the bearings, they were all bolted up to the columns and the rod was test fit in them - a little adjustment on the positions and they were all set.
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Next up will be the crank arms...
 
Got going on the crank arms for the reverse gear linkages today. There are three identical arms, that connect to the slide links, and one at the end (slightly longer) that connects to the lever in the cab through a set of u-joint type links. I got all four out of one bar of stainless - as before drilled all the holes first, counting off turns on the table to space them correctly with some extra between arms for cutting room.
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Then, turned it on its side and drilled holes into the larger holes on the three shorter arms - these will be the starter holes for the cross pins that will hold them in place on the shaft.
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With all the holes drilled, it was time to taper the arms. Tried a different method this time - set the bar in the vise at an angle (used the tops of the holes from one link as a reference line), and used the fly cutter in a series of shallow cuts to form the taper. With the first side done, it looks like a shallow staircase. The steps end just short of the next links' large hole, where it will be cut and rounded later.
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With the second side done likewise, you can see the taper in each link. This method worked well, quicker than setting up a jig to bolt them to, but it is critical to make sure the piece cannot slip in the vise - it started to on the second side since I had missed a spot with a bur from the first side. Fortunately I caught it in time. In this picture the longer arm is on the left end.
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Then it was just a matter of sawing them apart, and rounding the ends on the disc sander table (lots of dips in water to keep them cool). The longer arm is on the right in this picture.
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Then it was time to solder up the long arm and one short one to form the crank. Kozo gives the measurements for a jig bar to give a right angle. A little spacer ring is between the two arms.
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With the end cranks soldered up, next photo shows a test fit on the rod - the other two arms are just slipped on right now, they will get pinned in proper position later. Still need to make a couple more small rings that hold the assembly in place on the hanger blocks.
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Last photo shows the rod/cranks in position on the engine for a test fit.
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Next up will be to make the other rings, and then the connector arms that go to the reverse gear slides...
 
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Almost done with the reverse gear pieces now - been a fun day in the shop. First off, got going on the connector links from the crank arms to the sliders.Three are needed, and the closest stock of stainless bar I have let me get two out at a time. So, drilled the end holes in a bar long enough for two sets.
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Then rotated it 90 in the vise, and milled the center sections out, first one side then the other.
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After some rounding of the ends on the disc sander, put the links in the bench vise and sawed them down the middle to make the two pair.
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Then, some cleanup filing, and it was time to test fit them on the cranks.
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Last parts to make were the 'chain' that connect the lever in the cab down to the larger end crank arm. These are square links, with holes 90 degrees offset in either end. Two are same length, center one is a little longer (don't know why, that is what the book calls for. Seems like three equal length ones would work too?). Started like many other parts by notching the end tongues in on the mill on a longer piece.
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Then drilled the holes in the tongues, and 90 rotated ones in the blocks.
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After cutting them apart and sawing in slots in the square ends (fine hacksaw blade and filed smooth), all were assembled. The upper end will go on the end of the reverse lever arm I made a while back, at same time as the throttle lever.
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Last shot shows the new parts test fit on the engine.
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I am going to hold off pinning the arms in place on the rod though - this is a good time to do the painting on the engine. I will degrease the outside of the brass parts, mask off the crank/conn-rods, then airbrush on the black paint like the rest of the loco has. I may use that opportunity to do some touchup on the cab parts that were a little thin the first coat, and also paint the steam/sand domes. Its getting heavy to move around now! After painting, back to parts like steam inlet, exhaust, whistle....!
 
While waiting for the current coat of paint to cure up on the engine, I decided to have some fun and skip ahead to make the whistle.
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Since the scale whistle size would be an ear-splitting high note, Kozo designed a larger whistle that tucks behind the engine and up against the boiler. Since it is a larger diameter and longer tube, the note is much lower.

To start, found a length of tubing the right size (it is copper rather than brass, but I dont thing that will matter much to the sound), and then cut a shoulder on a piece of rod to be a push fit in the tube end. This will form the base of the whistle.
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Then, on the remaining length, cut a shallow cap piece to plug the far end of the tube - this piece was soldered into the tube.
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Back to the base piece, drilled a hole through for the steam passage. This end of the hole will be plugged with a bolt. It does not go all the way through, but meets up with the slot to be cut in a couple steps.
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Drilled a hole in the side that met up with the lengthwise passage. The hole was enlarged at the opening to take the screw fitting which will take the steam tube from the whistle valve in the cab.
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Then cut the slot in the side that the steam passage leads to. From this slot, a thin cut was made to the end to form the opening into the tube. This cut was just 0.2mm deep, so it does not show in the photos.
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Then, cut the opening in the tube that makes the turbulance for the sound.
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With the screw fitting and a mounting flange silver soldered on, and the bolt plugging the steam passage opening in place, the whistle is complete.
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Only way I know to get a sound posted here was to do it as a video clip - boring blank view, but the sound comes through. I was just blowing through the screw fitting for this - volume is lower than it will be but you can hear the note.

[ame]https://www.youtube.com/watch?v=YTeTbavIFCw&feature=youtu.be[/ame]
 
Note - found out that the video settings on the whistle video were wrong, that is now fixed and should be working properly. Sorry!
 
and it's humorous, too. 50 Grades of Shay...

Good start on "50 Shays on a Grade"!!!

Charles, awsome pic. Did you take that down at Cass? Looks like thier #6 at the front. Any chance of getting a high res copy of it?

Chris
 
Good start on "50 Shays on a Grade"!!!

Charles, awsome pic. Did you take that down at Cass? Looks like thier #6 at the front. Any chance of getting a high res copy of it?

Chris


Not my picture in any way - Think I got it from Facebook with a meme across the bottom.....wish I had that much talent.
 
Not the same photo, but probably from the same day, railfan weekend at Cass in 2013:

https://500px.com/photo/72689331/triple-header-by-jason-lowe?from=user

Also found this - a video of when that shot was taken, there were actually 4 shays altogether, one was back a little bit. Great vids...

[ame]https://www.youtube.com/watch?v=jv0w0spsMTc#t=150[/ame]
 
Quite likely correct - about 45 seconds in...even the red Louvre on the roof is open
 
After getting the whistle made, I realized that it would save removing/reinstalling the engine an extra time to also make the whistle valve and piping, since that connects down behind the engine. Also, the whistle valve hole would need to be plugged to test the engine on air from the boiler anyway. So, on to the valve. For once I happened to have a piece of brass hex stock the right size, so chucked that up and turned down the end to fit into the steam manifold that sits on top of the boiler in the cab. The end was drilled/bored to form the seat for a ball bearing check valve.
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Then, flipped it around and drilled/bored out the other end for the valve stem and o-ring retainer.
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After silver soldering on a square block on top to hold the lever, and a threaded connector on the bottom for the outlet pipe, it looks like the third photo.
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Next part was the plug that goes in the front end of the valve - this holds it in the manifold, and also holds the return spring for the ball bearing.
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Last part to make was the actuating lever. It was rough hack-sawn from stainless, then milled/filed down to shape.
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Next photos show the parts all made, and then assembled.
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Just need to make the tubing nipples and union nuts, and it can be installed...
 
This afternoon I got the tubing fittings made and installed for the whistle/whistle valve assembly. Really glad I did this before installing the engine - would not have been room to get the whistle and its fittings in otherwise. Getting the tubing the right length and the union nuts started was a royal pain in the exhaust with so many other parts so close.

Anyway, the union nuts were simple to make - drilled a through hole a little larger than the tubing through a length of hex rod, and drilled/tapped the end, and parted it off.
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The tubing nipples are bronze, and were made by first through drilling a hole, and drilling a shallow hole the diameter of the tubing. This is where the fitting will be soldered onto the tube.
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Then, used the parting tool to narrow down a neck to match the hole in the fitting this will all screw onto. Parted it off, and silver soldered onto the tubing.
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Then, a bunch of fat-fingered assembly, and the whistle is in place under the steam bracket. It will be un-noticed behind the engine. A scale-sized dummy whistle will be in the normal place atop the boiler - this larger whistle has a much lower pitch, wont be as ear splitting as a scale size one would be. With that done, and now that the paint on the engine has cured up, back to assembling the reverse gear linkage onto the engine. Once that is done, I'll cut the stop slots in the reverse gear hand lever rails, and can test/tune the valve timings for both directions. Lots of little fiddly stuff! Once all that is done I'll post another video of it running - probably be a couple days given other events here this week...
 
Got some plugs in for the water inlets, and hooked up the compressor to the boiler to test the whistle installation. Found a couple minor leaks in the snifter and throttle valve, have to sort those out - you can hear the hisses in the video. Here is a quick video of the whistle now that it is installed. You can see the whistle itself in the lower right corner - it is the round tube with the fittings on the left end.

[ame]https://www.youtube.com/watch?v=E-OZ0uaZKbY&feature=youtu.be[/ame]

Also got the reverse gear rod/arms installed, plus made the first part of the steam inlet pipe. Still need to make the elbow that takes it to the boiler steam outlet fitting. Below is a shot of those.
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I'd love to bring the engine to Cabin Fever if I can get enough together in time. Lots of progress the last couple days - just got the reverse gear links all pinned, and ran a test of it in forward and reverse. All went well, was some clatter that I traced to the center con-rods' locknut, which worked loose, plus the valve eccentrics rattle against each other a hair, but that is not a functional problem. I tracked down the leaks in the throttle and snifter, so that part is done. Still have some more pipe fittings to make so I can run it in the loco, and a biggie is working out a carry box that I can strap it down in the car with. If things keep on well this week, looks like I will be making reservations to hit the show! There will be no tender/water tank behind the cab (might make a cardboard cutout to show where it will be). Need to find out from you guys what the air hookup details are at the show so I can have that ready too - quick disconnects? 1/4-npt male/female, what? If I make it, I'll bring the loco, my double beam, and the marine triple engine.

Anyway, here is the running video - part way in, I shift the reverse link down to middle to stop it, then over to the other end to reverse it. It does run nice and slow at around 10 or 12 psi (at least according to the little gauge on the compressor). ;D

[ame]https://www.youtube.com/watch?v=TvP8KS-DThs&feature=youtu.be[/ame]
 
The last couple days I've gotten some more painting done on the engine and on the steam domes, plus reworked some gaskets that were leaking a bit.

Also took some time to install the CNC ready bearing/adapter sets on the mill. I am not switching to CNC, but these parts from Sherline solve a problem with their machines that have bugged me for a LONG time. They have a nice anti-backlash adjustment for the leadscrews, but the tables are held to the leadscrews in part by the handwheels. Not a bad way, as long as there is a way to adjust the pretension on that connection. But, there is NOT. They use a small grub screw through the handwheel into the end bar on the leadscrew. That screw never holds position that long, so you are constantly readjusting the fit, since the play builds up to a horrible level. With the CNC fittings, they used proper ball bearing thrust bearings, with a preload adjustment from the leadscrew. All I had to do was to make a little connector bar and plate to take the place of the stepper motor, and am back in business without all the play in the tables. Why they dont switch all thier machines to a setup like this is baffling - costly to rework old machines, but new ones could be done that way pretty easy. Okay, end of rant!!

Now, on to the steam pipe and exhaust pipe fittings. For both, there is an elbow fitting needed to turn the pipes into the boiler. They start out as a short length of hex bar stock, with a smaller hole drilled through and a larger one bored halfway through, all done with the four-jaw chuck on the lathe.
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Then, the bar was turned lengthwise in the 3-jaw, and the shape turned in for one arm of the final fitting.
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Then, a crossbar was made to fit the holes in the first bar, and to form the part of the fitting going off at 90 degrees to the first bar. The third picture shows the parts for both the steam and the exhaust elbows ready for silver soldering.
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Then, naturally, they were silver soldered together...
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and the hex and round extension parts of the bar used to chuck it up in the lathe for drilling/tapping the ends of the elbows (next three photos).
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The last photo shows the fittings all drilled/tapped, and ready to cut off/round over the upper and right parts of the fittings. Out of time for that today, will pick up on it tomorrow...
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Still going on the steam and exhaust pipes. I got the elbows trimmed down and filed the corners round. First photo shows the pipework so far.
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To get the pipes fitted to length, was finally time to install the engine for the (hopefully) last time. Turned out I needed to trim the slots a little in the engine cover, then I could start installing pipes. Next two photos show the engine in, and the steam pipe fit.
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Fourth photo shows the exhaust pipe fit. It is an inner piece of tubing, wrapped in insulation, and an outer larger tube cover. The elbow connects to a short length of tubing in the smokebox that directs the exhaust up the stack.
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Last part for the steam tube is the cover. In the real thing it would be an insulating wrap. In the book, Kozo shows to make a dummy cover out of wood, so I went down to the carving bench a cut s groove in two pieces of wood with a ball end rotary bit. The two halves are glued on, when set I'll trim and fair the outside to shape and install it.
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While fitting the engine, I found that the chain links for the reverse gear mechanism came up a little short, so I am going to remake the center link a little longer. Then I'll be able to cut the slots in the lever rack for the forward full/60%, and reverse full/60% positions. Once that is done, I'll start work on some riser blocks to fit under the truck frames. These will raise the wheels off the track slightly, so I can test run the engine on air without the loco leaving the room without me - that would be embarrising!
 

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