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Discussion Starter · #21 ·
Machined the pedestal binders today. These hold the journal openings rigidly in alignment and prevent them from spreading open.

These took a surprisingly long time to make for what they are. I started with 3/16” square stainless stock and had to cut one side to 5/32. To keep the stock from warping I cut .015, then .01” then .005” flipping the material each time so it stress relieved evenly. Then milled to length. After that there were two machining operations. Even with CNC it still took about 4 hours to make these, even though there was maybe only 30 minutes of actual machining time.

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Discussion Starter · #22 ·
Got a good start on the cylinders this weekend.

I have about 5 different CAD models of these cylinders, each with a different manufacturing approach in mind. Ultimately I decided the safest route was to fabricate them from multiple pieces

In appearance and function they will still very closely resemble the prototype. I’ve left machining stock on all the critical surfaces, so once everything is silver soldered together I can approach it like a casting. Still lots of little pieces to make before i can take a torch to it.

Now the chassis sits low in the front quite a bit.... I think it’s time to make the rear cradle to balance it out.

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Wow, talk about a 'bit' of an alteration to the original, this is fantastic work more like making one from scratch. I do like the rear truck especially that looks great and of course everything else, keep the photo's coming.
Russell
 

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Discussion Starter · #24 ·
this is fantastic work more like making one from scratch.

Thank you very much! The chassis is admittedly pretty much a scratch build... I had some reservations about calling this project a kitbash, but after the chassis is done I'll be dipping more heavily into the kit.
 

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Discussion Starter · #25 ·
Finished up the other pieces: the exhaust steam passages and the rib down the middle of the cylinders. All that’s left is bending up tubing for the internal exhaust passageways, which will be the trickiest part. Some tight bends in there...

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Discussion Starter · #26 ·
Bent up the exhaust passages. An initial attempt to bend by hand with some heat made it obvious that the bends were too tight, so a form tool would be necessary. After cutting up and soldering the pieces together, they were very carefully bent into the final shape and test fit to make sure they would clear the bottom mating surface to the frame.

The form tool made the first steps quick and easy but this was still a slow and difficult process, at least for me. I seem to be better at cutting metal than bending it.

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Discussion Starter · #28 ·
pjpickard,

I made a special tool to get some of the bolts that are in tight corners, but I also purchased a set of small nut drivers form Wiha. The set includes a 2mm hex nut driver, which is almost exactly the same size at 5/64" (.0006" difference). So I've been using that for most of the work. The set also includes 1.5, 1.8, 2.5, 3, 3.5, and 4mm.
 

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Discussion Starter · #29 ·
The cylinders are all soldered together now. There is some leakage between the steam inlet and exhaust passageways, but it may seal up with a process that’s used to seal up porous castings. Going to give that a try.
Once everything is tightened up the final machining can begin.

Soldering these together was very unnerving for me. My only experience with silver soldering is pretty much limited to small fittings and details. Something this large with this many pieces was challenging.

Gauge pins come in handy for much more than checking hole sizes. Here I’m using one to locate the centerline of the steam chest.
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Discussion Starter · #30 ·
Progress has slowed a bit lately, but I managed to get the crosshead guide yokes cut out last night. The detail really popped after bead blasting them.

Earlier I mentioned that the link hanger castings didn’t shrink at all, making them too large to use. So I had them remade and this time I didn’t add any shrinkage factor... and they shrank! So now the new set is too small. I’m just going to machine them... will lose a bit of detail but what’s lost will be hidden anyway.

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Tony,
Is everything OK? I am having withdrawals because you have not posted in a long time.....
Best Regards
Noel
 
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