Shop Notes 1/20 - Steam Engine Build, final stretch edition

Synopsis: I've been working on a steam engine casting kit this past month, finally coming to the last few components before I can actually run it😛

The majority of the work is done, with the bulk of the remainder work having to deal with the valve and eccentric (sets the timing and shuttles steam back and forth in the cylinder).

I had roughly finished the valve bore, but opted to finish with a reamer to save a couple hours of targeted polishing/sanding in the bore.   Using a boring bar tends to result in a more 'scratchy' surface that's harder to finish.

Not my proudest setup, but it worked like a hot damn.  Fast and accurate.

My first time using the pin reamer to secure the crank wheels to the shaft.   It's not in the print, but I figured I'd rather have it secured so that it will never ever slip, and also be relatively easy to disassemble if needed.

Whole process was pretty simple, and the end of the pins were cut and sanded flush using a dremel wheel.

Onto the valve....

This took several passes to get the valve to fit in the 'barrel', but it ended up a nice running fit.

The valve exhaust was fairly straightforward.  Made the main dimensions on the lathe, then used the 'super glue trick' to secure+indicate the part on the mill so the mounting holes could be drilled accurately.

Lower valve was a little bit trickier due to the threading but still didn't take too long.  Helluva lot faster than the one I mad last year (probably took a day to do just one of these)

Here's the lower valve assembly *almost finished.  Just needs the packing nut on the bottom

The 'packing nut' is usually filled with usually graphite or teflon yarn used to seal the rod completely against steam pressure and prevent leaks.  Usually it takes a little tweaking in the beginning to get a good seal while also limiting friction.

Status:

All remaining is to machine the eccentric (cam that opens+closes the valve at the appropriate timing) and hinge/rod to link it to the valve.

If things go well, I might be able to do a rough dry run tomorrow.🥳

Hope you enjoyed.  Stay tuned for tomorrow and this weekend where we'll finally start to see it running.🤠🤞