Building Kozo's New Shay locomotive

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That's lookin beautiful!

Stay safe out there in the weather. Crazy winter in Western NY already.

Todd
 
Last couple fittings on the smokebox - the mounting lugs that attach the assembly to the frame. These will get a pair of links that drop down to the frame and allow the boiler to expand/contract with heating.

Started out with a pair of square bits of sheet brass, bent to match the curve of the boiler with pliers/vise. Then mounted them in the mill vise at the proper angel, and plunge cut with a 1/4" mill.
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Then took a 1/4" piece of brass rod, drilled into the ends on the lathe for the link bolts, and silver soldered them to the plates (distance betwen plates was just for the piece of rod handy, is not measured out for the boiler).
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With the rod cut in half to separate the plates, they were put in the lathe and the square ends turned round. Looking at the end of the rod the plates look round, since they are at an angle they appear oval from the side.
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Then put them in the mill vise with some scrap to hold them above the jaws, and drilled holes for mounting screws.
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With matching holes drilled/tapped in the smokebox, next few photos show the mounts in place.
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Last photo also shows the headlight bracket - simple piece made up from some sheet stock. This will hold the headlight, and also the ends of the handrails that run along the boiler. These will both be made later in the build.
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That finishes up the smokebox, about all I can do till the final boiler staybolt/front plate soldering/testing is done. Still looking like it will warm up (finally) this weekend, hope to work on that stuff then. Once the boiler front plate is soldered on, I can drill the last mount holes for the smokebox to hold it to the rest of the boiler. Also, will need to do some tweaking to the boiler support braces in the main frame - Kozo has you leave them a little tall to allow for any actual variations in the boiler. In my case I need to lower the tops of the supports a few millimeters to have the boiler sit where it should relative to the frame. At that point, it should really start looking like a locomotive - can't wait!
 
At last, weather is back to decent to work outside, got the staybolts soldered inside and out, plus filled the two leaks I knew about. Time to clean it up again, put in the plugs, and do one more fill/leak test. If it passes that I'll solder on the front plate tomorrow...
 
:wall: :redface2:
Let's see, how can I say this and not be too explicit: Politician-Poo! Swarf-Stuff!!

Did not get past the leak test. One spot on the back wall of the inner firebox seam leaks, fixed part of it but apparently it extended farther to on side. That needs some rework, plus two small spots on the conical section to middle section seam leaks. Not as suprised there, that was first big joint I did, and struggled with the smaller torch there. That one is easier to fix than the firebox. So, will take a shot at those tomorrow and test it again before attaching the front plate. Hopefully it works then!
 
Decent progress today. Got the leaks patched successfully, and got the front end plate soldered in finally! Give that a while to cool, and will check that for leaks. If okay, can prepare for the static test...
 
This morning I got the last of the known leaks reworked, and they passed the fill-with-water-and-watch-for-leaks test. Just tested the joints on the front plate, which I soldered on this afternoon, all is good! Major milestone - ready for static test on boiler. Passing THAT will be a huge step forward. I need to make a tube set to go from the pump to the boiler and a fitting for the pressure gauge first - had held off on that part not knowing if I would need them or not!

Happy Happy Happy!
*beer*

Oh, had one head-slap moment on the final leak test - I put in the plugs on the bushings at the front of the boiler, tipped it up on its front end, and put in a funnel in one of the backplate openings. Poured in some water, and WOW, did it come gushing out fast from the front end. What the heck! Cant have been that far off on the joints! Umm... took a closer look - I had poured the water into the hole that leads to the blast tube, which runs all the way down the boiler and straight out the other end. It is SUPPOSED to go right through. Whoops! :hDe: Moved the funnel to the water guage bushing, filled the boiler that way... Much better.
 
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A few photos of the boiler progress so far, while I am in process of making the fittings needed for the static pressure test. The brass cylinders to the left in the first photos are the boiler jackets, which wrap the middle and conical sections. On the real locos the jackets were an insulated layer around the boilers. In his book, Kozo mentions he left out the insulation to get the maximum volume of water in the boiler - the insulation is not as important on the model as on the real thing. Last two photos show it sitting in place on the frame.

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Got the fittings made to plug the bushings and provide connection to pump and pressure gauge. On first try for static test, found one pinhole on the top seam - looks like an air bubble, gave a teeny stream of water squirting across the sink, plus one outer staybolt head that seaps. Not bad, will redo those joints and try again (got other stuff needing to be done today, so will probably be a day).

One other issue, the thread sealant goop I tried is worthless, at least without a really long dry time. Going to go back to old standby teflon tape on second try. No good pressure testing and having the pump fitting leak! Anyone have other options for sealing threads?
 
Got those leaks fixed, and got the fittings sealed well. One leak is the o ring on the hand pump, have to fix that now. Did get up to about 120 psi even with the pump leak, which showed two more teeny pinholes. With the holiday here, will be a few days till I get back to it, but am making forward progress. Depending on the weather then I'll either work on the boiler or skip ahead to the cab.
 
Hope you had a great Thanksgiving. Good to see you making more progress. Good luck with the hydro!

Todd
 
Hope you had a great Thanksgiving. Good to see you making more progress. Good luck with the hydro!

Todd
Thanks - Holiday went great (still is). Got some side projects to finish for birthday/christmas presents, then will get back to the boiler. I realized that the leak at the pump wasnt really a problem with the plunger, but that the check valve at the outlet must not be sealing right. Also, to make it easier to move the boiler around during the test, to see underneath it, etc, I am switching the hard copper tubing I connected the pump to the boiler, with a short length of air tool lead-in hose, which is flexible and has plenty of pressure rating.
The weather is cold/snowy again right now, going to warm up Sunday and Monday, so am planning on going back to work on it then. One by one knocking down the leaks.... Learning a lot this way, wish I could start over on the soldering with what I know now, but that would be WAY too much work!
 
SO close.... But not there yet. The new hose setup from the pump works great, and I got the few known leaks fixed. But, now that I can get the pressure up high, found that there are a couple more, and one known one did not get fully fixed. Sigh....
Pressure goes up to 160 psi+ easily, but with the couple seaping spots it drifts slowly down again, gets real slow down around 50. About a drop of water out every 6 to 10 seconds. Still some work to do on it. Good news is no movements or bulges anywhere. Kozo has it designed very well, just my sheet bending skills are not as good! The first couple seams I did are the worst offenders, which shows the learning curve.

Given the back and forth weather, which is normal for western New York state, think that I am going to skip ahead and work on the cab and tender during bad stretches and go back to the boiler during warmups, which usually happen every week or two till a real cold stretch in February. That way I can keep the progress going.

Onward!
 
Boilers are finicky creatures aren't they? ;) I'm sure you'll tackle it. Look forward to your continued progress.

Todd
 
Boilers are finicky creatures aren't they? ;) I'm sure you'll tackle it. Look forward to your continued progress.

Todd

They sure are! I'm off on a couple side projects for a couple days, getting some birthday/christmas presents made. Should be back at the engine soon...
 
Okay, back in the shop again! While waiting for the next batch of warm weather to arrive to do more boiler soldering work (we usually get a couple warm days every week or two this time of year, good thing too, or the snow would get really deep by end of winter seeing how we get anywhere from 60 to 160 inches a year!), I am going to skip ahead a chapter or so in the book and work on a simple/fun section, the cab and tender. The cab pieces are just soft soldered, so can do that work indoors. The few bits that are hard soldered are small, can use the little butane torch for those.

Started out with cutting the sheet brass for the roof/sides of the cab. The window openings get cut later on after the frames are in place, so for now just the outlines are cut.
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Then, cut the brass bar stock for the edging pieces, and milled the ends to square them up and take them to final length.
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Last photo shows these pieces laid out in place, ready to drill/tap for some small screws to hold them for soldering. Also, there are mounting holes to be drilled in them. Will get to that part later today probably. Got to get up to the range and get my bow sighted in before the winter leagues start, so may not get to soldering these pieces till tomorrow.... Nice to be back fabricating again - these pieces will change the look of the model really fast.
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Nice. I've been considering whether I could make a wooden cab for my A3.

Todd

It would get a lot of heat, especially the front wall where it wraps around the boiler. Panel inserts and coverings might be okay for detail.
 
It would get a lot of heat, especially the front wall where it wraps around the boiler. Panel inserts and coverings might be okay for detail.

That's true. There is no insulation between the boiler and jacket. And, there is no jacket in the cab at all.
 
Got the cab side frames drilled for mounting holes, and then screwed and soft soldered to the panels.
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After soldering on the extra panels that will make the window frames, filed off the screw heads flush with the panels. Second photo also shows the roof panel, bent to an arc and with the drip rails soldered on (hard to see in photo - they are angled up along the sides).
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With the side panels clamped onto the mill table (the frame bars hold the sheet off the table) I milled out the openings for the windows and insert panels. In the book Kozo saws them out, but I think this was aquicker and straighter way to do it. Next few photos show milling out the openings in the two side panels.
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Last photo shows the two sides with all openings made, ready for filing the edges nice and smooth. Next step will be to drill/tap the mounting holes for the insert panels, and add the window sill below....
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Today I got the inserts for the side panels cut, and the ones that simulate wood planking scored. Did that with a high speed rotary air tool (like a dentist drill - wonderful sound...) and a tiny (0.5mm) cylinder cutter run along a straightedge.
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Last three photos show the pieces after screwing the inserts into the left/right side panels, and the sides/roof propped up together to see how they look. Roof is not attached yet - that will get held by hinges from the front panel (not made yet - roof first, then scribe that curve to the front sheet).
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I like the look - really going to change the appearance of the loco in one step. Next will start on the front panel and the floor.... Weather is still lousy, so this is more fun that fussing with the boiler outside!
 

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