Sunday, February 04, 2001
The New England Rubbish Deconstruction Society
So, it wanted to start in reverse, but we wanted to go forward? No big deal, we left the transmission there for just this class of problem. Our solution: “reverse-reverse”. To get rolling, we would start with the transmission in reverse, and the engine controls in "full gear" reverse. Once rolling we would switch both engine and transmission into a forward gear, in a process of complex coordination that deserved the “fire drill” name it got.
This was a four step process that had to be both done quickly and be coordinated between driver (controller of the shift lever) and motorman (throttle, and Johnson bar). At a signal, the motorman closed the throttle, and started moving the Johnson bar. (This was held from moving by a wing nut, which took pliers to budge). Once the throttle was closed, the driver would start to shift. The shift took time, as the crankshaft (with flywheel) was spinning not just at a different speed (like trying to shift a car without the clutch), but in the opposite direction. You had to use the synchronizer to help bring things to a stop. The motorman would announce that the bar was locked in place, and (in the eventually adopted system) the driver would open the throttle, once the shift was completed. We even managed to shift correctly some of the times during the race. We also blew a few, luckily without any real trauma to our engine. Our coupling system did take some significant knocks while learning to do this. Anything less than the motorcycle chain we chose would have parted.
While steam engines are not the best at containing all their fluids, ours seemed worse than usual. We discovered that the piston gland leaked, as, to a lesser extent, so did the cylinder end covers. Again, with the luxury of testing time, we were able to find the problem and after a bit of tightening, we were significantly reduce (but not eliminate) the leaks. We didn't have to put up with the power (and steam) losses they represented, because we didn't find them until we were actually racing.
I came across the The New England Rubbish Desconstruction Society; The NERDS, which is an American team that has appeared on the Brittish TV show Scrapheap Challenge (Junkyard Wars to those Brittishly challenged). Fascinating reading. The wet-sub. The steam powered car. Stuff that sounds so fun to do, and underscores just how much math and science it takes to have real fun.
Just reading this makes me realize just how little I really understand of mechanical engineering (as if I really needed reminding of that).