I'm starting to wonder if I'll be finished by Valentine's day

. We just got hit with 16" of new snow in a day and a half, on top of what we just got before, and temps and wind were miserable -- I plowed and shoveled twice -- it was blowing and the high for the day was -12C. This morning we awoke to -24C, and I had to shovel again because the big road plows had blocked the drive entrance and thrown snow 20 feet in.
Anyway, the shop is finally too cold to stand working for more than 5 minutes at a time. But to catch up verbally, at least, I made 3 different valves and 3 valve chambers so far, and drilled the exhaust ports. I've tried running the motor, and have made as much as 3 revolutions before it stops. The main problem has been the valve -- I was getting some leakage past BDC, which stopped her. I think the latest valve/chamber version is a definite improvement.
I also think the intake timing is too short for running on compressed air -- though it might be okay for steam. So I've been gradually delaying the cuttoff by filing the cam. The valve height is really critical too, and might need more trimming -- but that's easy to overdo -- as I have already, twice!
The flywheel is also on the small side -- in keeping with the style of high speed steam engine this one is reminiscent of -- but maybe too small. So I added another layer of pipe, brazed on, to increase diameter.
I think right now it's borderline wanting to run. I just need to figure out the valve and timing adjustments. I may need to make a new cam with more lift to get a better seal at BDC. And I may need to add a valve spring, then. Right now I'm just using feed pressure to keep the valve against the cam.
Anyway, I hope we get a little more warmth -- so far it's been a longer deep cold period than we've seen for years here. Plugging away on the engine a little at a time, anyway.