With special guest star: The World's Best Mechanical Engineer.
Joe-Henry of Mommy's in a Timeout fame had some questions for the World's Best Mechanical Engineer. Many, many questions, actually -- as a six-year old boy is wont to have.
Here's one puzzle made plain by the b1-67er, aka the World's Best Mechanical Engineer:
Q. How do the doors on the Max train open?
A. I'm not familiar with this particular train, but I can probably answer this question right anyway. Almost all doors on trains that are automatic are pneumatic. This means that they are moved with air. Air is blown into a device called a pneumatic cylinder. It is basically a tube that is plugged at one end, and has a movable rod plugging the other end. When you blow air into the tube, the air pushes the rod out of the tube.
To see what I mean, go to Taco Bell. Order a large Mountain Dew. Make sure to get a straw that is covered that is covered with paper. Tear the paper off of one end of the straw, but leave the rest of the straw covered with paper. Blow hard into the open end of the straw. The paper cover will go flying off of the straw.
Congratulations, you've just made the world's cheapest pneumatic cylinder. Celebrate by drinking your large Mountain Dew.
The beauty of pneumatics is that they push hard, but not so hard that you'll squash someone like a bug. Pneumatics are lightweight and can be fit into pretty small spaces, like the train door.
(Did I mention that he's the World's Best Mechanical Engineer?)
Also in this series:
holy hydraulics, batman!
springs & things