OK, So I’d Make a Lousy War Correspondent
"We now take you to our correspondent in War-Torn Wherever, Benjamin Hutchins. Benjamin, what’s going on there?"
"Well, Bob, uh… not a lot, right now. But the locals tell me things were cuh-razy around here a month ago! Boy howdy!"
I think what makes me a lackluster blogger is the same thing that’s always made me a poor diarist and an indifferent correspondent: I don’t feel justified in posting or writing to someone unless I’ve got something interesting to report, and often I have a hard time feeling like I do. This is particularly true at the height of the semester, when it’s basically "Well, uh… went to class, did some homework, went to the next class and turned it in."
Still, the semester’s just about over now (there’s only finals week next week, and by an odd coincidence only one of my classes this semester even has a final),and there have been a few interesting developments to report.
Taking the most recent first, the final engine tests in MET 107 were conducted today. As you may recall, at the start of the semesters we were split up into teams of six and given a list of required parts (and the prints from which to make them), with the ultimate goal of building a single-cylinder pneumatic engine by the semester’s end. On the prints it’s called a steam engine, but since we didn’t actually have a boiler handy (for safety reasons), we drove ours with compressed air. We all got together in the machine shop this afternoon and ran our engines while Prof. Anderson timed them with a strobe. (An engine that didn’t run would have constituted a major grade deduction.)
The team I was on, Team 2, went into the competition pretty confident.
Fig. 1 Team 2. From left: author, Ben White, Bill Long, Clark McDermith, Cam Terry. Not present: Mike Peasley. Photo by Herb Crosby
We had all our parts done by the beginning of this week and were doing test runs by Tuesday evening. Bill, one of my teammates, had access to a deburring mill at his job and had spent a lot of time obsessively polishing all the parts as we finished them and turned them over to him, so ours was by far the shiniest engine…
Fig. 2 Engine No. 2. Photo by Herb Crosby
… and once we overcame the fact that I apparently can’t drill a concentric hole in a brass bushing even with the tailstock of a lathe (sigh – I must have scrapped eight of those damn things), it ran as beautifully as it looked. Bill could actually make it turn over just by blowing into the intake, and since the test pressure was 100 PSI (er, rather more than the average human output, I should think), we had high hopes.
The first run demonstrated that we might actually have done a little too well at the polishing and fettling, as, well, this happened:
We actually blew the valve rod bushing right out of the steam chest on the first run. (Amazingly, this was not the bushing I had so much trouble with. That one had the piston rod running through it and performed perfectly in the actual test. For the technically curious, I made the base plate, the columns, the piston rod bushing, and the piston.)
Fortunately, we had time to tear it down and fix the problem before our second run.
Fig. 3 Engine #2 down for repairs. Photo by the author
A couple of false starts, some hurried consultation, a helpful senior, and a few minutes’ work with the scissors in Bill’s Leatherman, some brass shim stock, and the arbor press, and Team 2 was back in business. By then the other teams had all had their runs, the fastest of which clocked a top speed of 2287 RPM, so Bill and Cam stepped up to the testing bench, and…
… 3266 RPM, baby. The fastest entry this semester, and only 480 RPM shy of the all-time record, 3746. (Bill’s sure we could get it going that fast if we had more time to futz with it.)
So hey! Victory. It’s what’s for dinner. (Apologies for the crap camera work. Bit excited.)
More news to come, and it’ll get steadily more out of date as the posts go on…