Building Kozo's New Shay locomotive

Home Model Engine Machinist Forum

Help Support Home Model Engine Machinist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
very nice work , how long is this going to be ??
32 long but how hi and heavy??

Thanks! It is 32" long, 7.2" wide, and 10" tall. According to the book it should be about 55 pounds without water - already the frame/trucks are about 21 pounds. I am building it to the plans in Kozo's book, so it is 3 1/2" guage, though he also gives instructions for a larger version at the end of the book (my lathe/mill are not big enough to do the larger version, plus I dont know where I would put it!).
 
Got a start on the brake pads - in Kozo's book he shapes them from a large diameter disc of brass, angle undercuts the inside to match the taper on the wheels, then cuts them apart. In my case, I did not 1) have a piece of round bar 2.75" in diameter or 2) have a way to turn it without putting in the riser block on the lathe, or even 3) have a riser block for the compund slide.

So, using what I do have, I came up with an alternate method that probably took a little longer but got me to the same shapes in the end. What I did was take some offcuts of brass (left over from the journal boxes, when I cut the square stock down to rectangular), and mounted them on the rotary table with the mill vise on top. The ends of the brass were set to one side so that by turning the rotary table it would mill an arc that matched the outside diameter of the wheels. This was done with the table tilted 3 degrees so that the arc on the pads would also match the taper on the wheels. The aluminum block in the photos is there to raise the brass above the vise, so I did not cut into the vise jaws.
IMG_4524.JPG
Once the arc was milled in, I lowered the tilt table down to level again and milled in the recess behind the brake pad.
IMG_4525.JPG
Then the pad was cut from the larger block, and the back of the block milled to size, with a notch in it for where it will mount on the cross beam. The ends were also milled down to size and a 2-56 hole drilled/tapped in the corner for the brake hangers (not made yet).
IMG_4529.JPG
A test fit of the pad against one of the wheels (the spare one left over from the wheel construction) showed that the arc and angle all matched, so then I went into mass production mode and made the other 7 pads.
IMG_4530.JPG
IMG_4532.JPG
Then, took a length of bar stock, and milled it down to be an I-beam shape (I think in Europe you guys call it a RSJ shape?)
IMG_4536.JPG
Then, the pads were silver soldered onto the ends of the beams (at the right distance to match the wheel spacing - checked that about 5 times!) along with a small bracket in the middle that will hold the actuator linkage.
IMG_4539.JPG
 
Great looking shoes! Just proves that better/bigger/more tools don't make the craftsman. Using what you have to get the desired result is real craftsmanship. Keep it up! Looking awesome!
 
Thanks guys!

Got the brake hangers made - need 16 of the little links, and the thought of making them individually made me cough up some swarf, so dug out an old small-part trick and ganged them up. Started with a couple slices of off-cut bar stock (think these are left over from the journal boxes), and drilled through holes for the links in both,
IMG_4540.JPG
laid them on thier sides and milled a slot down each side to form the center of the links,
IMG_4542.JPG
then filed the ends round.
IMG_4543.JPG
At that point the two pieces had the proper shape in two directions, so it was just a matter of running them through the slitting saw to make the individual links. Got enough to make 9 from each before the blocks got too thin to hold for cutting.
IMG_4545.JPG
A little deburring later, and they were ready to screw onto the brake beams. The last photo shows one propped up in position - still need to make the pivot bars (just a short length of rod notched for e-clips. Wonder how many of those little buggers will fly across the room during installation...)
IMG_4546.JPG

Got some nice weather rolling in for the next week, time to get out the boats and go play on the water!
 
Okay - got the brake assemblies mounted, and the trucks painted. Below are some shots of it with the trucks/frame together. Some more parts still to go on the trucks (brake actuators, and lube/feedwater pumps), but they would have been in the way to paint, so they will be painted seperate and mounted as they are made.

Farther along than I thought I'd be by now, still amazing to see that I am only up to about page 54 of Kozo's build book, only another 200 to go! :eek:

DSC_1441.JPG

DSC_1411.JPG

DSC_1427.JPG

DSC_1413.JPG
 
A beautiful bit of work. Makes me want to get out to the shop and start on one myself.

Thayer
 
A beautiful bit of work. Makes me want to get out to the shop and start on one myself.

Thayer

Go ahead and start, you will have fun too! :D
 
Oh, I don't doubt it. The issue comes with all my other distractions, that pesky thing called a job, and my fiscal obligations to my family.
 
Got the rest of the levers/rods/etc for the brake actuators done and installed - really tricky figuring out what order to put it all in place, not much room to get nut drivers/wrenches in between all those struts.

Started out with a couple of sets of pivots for the cranks, which were milled out of some 1/4" square bar.
IMG_4547.JPG
Then went into mass production mode on the 22 clevis ends that were needed - gang drilled the cross holes for all of them on one bar, with the holes far enough apart to account for the part plus thickness of the slitting saw.
IMG_4549.JPG
Then sawed in the slot in the end, one at a time, cut them apart, and drilled/tapped the hole in the end for the rod.
IMG_4552.JPG
Made up a set of crank bars,
IMG_4548.JPG
and test assembled everything. The long crank rod and the last clevis mount on the lower bolster of the truck, and the outside cranks pivot on the I-beam holding the brake shoes. When the brakes are activated, it draws everything up tight against the wheels. When I was looking at the plans, it took a while to visualize how it all works.
IMG_4554.JPG
A coat of paint, and a bunch of fiddling to get it all assembled, and it all looks good. I need to go back and touch up the paint in some places where I scraped it up during assembly.
IMG_4557.JPG
While waiting for paint to dry, I got a start on the lubricator pump housing, which is driven from one of the eccentrics on the axles, and pumps oil up to the steam chests on the engine. Some small brass screws are there to hold it all for soldering, they will be filed off after the silver soldering is done....
IMG_4555.JPG
 
I got the lubricator pump housing silver soldered up and milled to shape - your basic little box, with a sliding lid. This pump is driven off an eccentric on one of the axles, and will send oil to the three steam chests. The pump bodies screw into the bottom of the box, and will have a spring loaded steel ball to act as a check valve.

The pump bodies were turned down from some hex rod, with a thread to go into the box and a protruding rod to hold the return springs for the plungers (made later).
IMG_4561.JPG
After turning one end of the bodies, a piece of round bar was chucked up and drilled/threaded to act as a holder while turning the other ends of the bodies. To make sure it all stayed concentric, the holder was left in place till all three were done. The other end of the bodies were drilled in a sequence of sizes to form seats for the check valve balls inside, and finally tapped for the spring holders (made below).
IMG_4566.JPG
Last on the bodies was to cross drill a number 60 hole at the end of the threads to make an inlet for the oil - this hole winds up just on the inside edge of the bottom of the box. Nearly missed this step - Kozo does not mention it in the text, was wondering how the oil intake worked for a while and finally spotted this hole in one of the diagrams. Been a few cases like this from the book - the text is sparse in a lot of places - he tells you once how to do a procedure, then assumes you will remember things for the next time around. That is fine, but in places where he goes into great detail in the text on part of a piece he says nothing about the other portions. Still, better than having plans with no text!
IMG_4571.JPG
Fourth photo shows the progress so far, with two of the bodies screwed into the box. The sliding lid of the box is visible at the upper right - the hole in it is to provide a finger grip. The flange with two holes at the top of the photo is the mounting plate for bolting the pump to the upper crossbar of the truck.
IMG_4572.JPG
Next up was to make the spring holders, which hold the springs for the steel ball check valve. They are made from a smaller hex bar (8mm), and were threaded one end, drilled for the OD of the spring, and then through drilled #60 for the oil passage.
IMG_4576.JPG
The holders were then turned around, and held in the chuck using one of the pump bodies - the area of the hex remaining at that point was too small to hold securly in the chuck. The second end was turned down and threaded.
IMG_4579.JPG
The last two photos show the pump body assemblies test fitted to the box. The steel rod through the box is the axle that the pump eccentrics (3 lobes, one per pump body) will fit onto. Lot of stuff to fit into a little box!
IMG_4582.JPG
IMG_4584.JPG
 
Beautiful work. I'm not a locomotive guy, but just admiring the machining. Couple questions

- is the extensive brass use prescribed in the original Kozo design, or you are opting over steel for particular machining/silver soldering reasons?

- your frame painting looks so great. When you described as below, what is 'grill paint' & how did you reduce it? Is it a 2-component catalysed paint or single stage/ambient cure?

I used some satin-finish high temperature grill paint, thinned down and airbrushed on. Below are some pictures of it sitting out in the sun to cure up
 
Beautiful work. I'm not a locomotive guy, but just admiring the machining. Couple questions

- is the extensive brass use prescribed in the original Kozo design, or you are opting over steel for particular machining/silver soldering reasons?

- your frame painting looks so great. When you described as below, what is 'grill paint' & how did you reduce it? Is it a 2-component catalysed paint or single stage/ambient cure?

I used some satin-finish high temperature grill paint, thinned down and airbrushed on. Below are some pictures of it sitting out in the sun to cure up

Hi Peter,

Kozo uses mostly brass for structure in his book for the 3/4":1' version, some steel for axels/wheels/cranks/etc, and copper/bronze for the boiler. At that scale it is plenty strong, and very easy to machine. I did swap steel for the frame rails for lower cost, but am sticking to brass for everything else. I was able to get some good bargains on the larger brass from Yarde Metals Drop Zone, where they sell offcuts at a discount. He may also have picked it to add weight for traction. In the 1 1/2" scale version at the back of the book he calls out more items in steel. With my smaller machines and no coolant spray the brass is more easily worked and easier on my cutters.

For paint, I am using rustoleum grill paint, thinned down about 50% and applied with an airbrush. Gives me great control on placement, about a 1/4" spread pattern, and it goes on thin with a matte texture. Later on the white lettering will be applied same way, through a self adhesive plastic template. I use a printable plastic film for painting and also to make templates for relief carving and scrimshaw patterns. Usually use the airbrush on my carvings, first time use on engines was this one - spray can gives too big a pattern to get into all the details on the trucks/frame.

Chris
 
Last edited:
Brake rigging and pump look great. I like how you approached the brake rigging machining.

Todd
 
Got most of the rest of the lube pump done (waiting on an order of a bunch of sizes of steel balls for check valves, and viton rings for pistons/shafts/etc for the rest of the engine). The pump plungers are simple shafts with discs silver soldered up at the tops, to ride on the cams.
IMG_4587.JPG
For the eccentric straps, was about to dig out some flat bar stock, when I noticed that Kozo milled his down out of discs of brass - I happened to have a piece just big enough left over from making the bevel gears, and split it down with a parting tool on the lathe to make two discs, one for each pump strap.
IMG_4592.JPG
Before sawing the disc into two halves for top/bottom of the strap, I milled in some flats and drilled/tapped for the bolts that will hold the straps together. Doing it now meant that the two halves would line up correctly.
IMG_4594.JPG
Then sawed the disc in two (not in the center, since there is a protrusion on one side to attach the conn-rod) with a slitting saw.
IMG_4595.JPG
With the two halves screwed back together and held in the 4-jaw (one jaw turned around to give clearance to the lathe bed), I bored out the centers to match the eccentric diameter (the eccentrics were made along with the wheels, and are already on the axles).
IMG_4599.JPG
Then moved to the mill, and held the strap from the inside with the 3-jaw on the rotary table, and milled the arcs on the outside, leaving the bolt extensions and the con-rod flange. Kozo did this without a rotary table (dont think he has one, never saw it in the books). He held the strap on a vertical post, and did a whole lot of plunge cuts, moving the strap a little around the post between cuts. Much faster with the table, though end result is the same.
IMG_4600.JPG
Last step was to slot the attachment flange with a slitting saw.
IMG_4604.JPG
Last photo is the pump assembly on the left, and the eccentric strap for the feedwater pump on the right. That pump and the hand-pump come next.
IMG_4608.JPG
After that, the real fun begins - the boiler! Gulp. :hDe:
 
I can't believe you're that close to the boiler already! Those eccentrics look great.

Todd
 
Got a start on the second axle pump, the boiler feedwater pump (there will also be a manual pump used to fill boiler and also to do hydrostatic tests).

This one is pretty straightforward turning so far - I noticed that so far on this build the vast majority of it has been mill work, very little lathe time, opposite of most of my projects.

The pump consists of two bars joined in a T shape, with check valves at each end of the crossbar for inlet/outlet, and a slide that will move up the body of the T to move the water. So far, have the parts made
IMG_4610.JPG
and test fit ready to silver solder together (burned my fingertips on a hot offcut from the plate, so taking a day before getting out the torch. Turned out to be a perfect detector for a slitting saw blade going dull - that sucker got HOT very fast rubbing on the brass, though it cut okay. The blade, a cheap one, had worn down the set of the teeth enough to rub. The plate is C260 cartridge brass, which did not help. This is about the last of the 260 brass sheet I had, be glad when that stuff is gone - much prefer the C360 alloy for everything. Wont buy it again if I have a choice!).
IMG_4609.JPG

The flanges on the base plate are screwed in place for soldering, after soldering the base plate gets trimmed down to final dimensions and the screws heads filed off.
 
Nice looking parts there. :)

Todd

Thanks - just got back from a trip to Cass, West Virginia. There is a state park there that has 5 operating Shay engines, an operating Hiesler, and a Climax that is under restoration. They take trains up the old logging rail up the mountain there (up to 4700 feet) - fantastic place for steam engine junkies! The track is so windy that from one car or two back you get a nearly straight side view of the engine, and the grades go up past 9 percent. I am starting to get a ton of photos off the cameras, will be uploading some of them later on today.... Here is one to get started,
DSC_2608a.JPG
plus this one is a shot of my boiler all done - didnt it come out great?
DSC_2289a.JPG
Okay, busted - it is one of thiers in the shop - might be the one from the Climax engine.
 
Here are links to some videos from Cass of the trips on the Heisler and Shay engines. Great incentive to keep working on my model! Also took a ton of detail photos of thier engines for reference. Thier website is:

http://www.cassrailroad.com/

If you are anywhere near West Virginia, I highly recommend taking a trip over there to see/ride. I dont know of anywhere else with that many Shay's still operating regularly.
[SIZE=-1]
[ame]https://www.youtube.com/watch?v=D56DUJAcATs[/ame]

[ame]https://www.youtube.com/watch?v=ufAkbULIt1s[/ame]

[ame]https://www.youtube.com/watch?v=XBnOhObSslg[/ame]

[ame]https://www.youtube.com/watch?v=bcxlyrVsUxY[/ame]

[ame]https://www.youtube.com/watch?v=V7uNDmel9U8[/ame]

[ame]https://www.youtube.com/watch?v=FEts5HV71xM[/ame]

[ame]https://www.youtube.com/watch?v=p8rhUcCYV80[/ame]

[ame]https://www.youtube.com/watch?v=7YkqtPhkNus[/ame]



[/SIZE]
 

Latest posts

Back
Top