Tinkering

• The term "No user servicable parts inside" means:
  • Darn, I can't fix this thing.
  • "I should have this repaired in about an hour, ma'am."
  • Those danged bureaucrats in Washington! They don't let us fix things or repair things or let us do anything technical any more! Why don't they bud out?!
  • Those danged lawyers at the company who built this thing! Do they really think I am going to sue them if I mishandle the high voltage/laser/CPU in this thing?!
  • Those danged marketers at the company who built this thing! Do they really think I am going to sue them if I mishandle the high voltage/laser/CPU in this thing?!
  • I am unfamiliar with the term. In what context does it appear?
• What interesting things can you do with potassium nitrate?
  • Make a tiny bit of gunpowder as a demo for the kids. Maybe one of them will grow up to be a chemist and get a Nobel prize. (For enough gunpowder to make a cooler demo, don't make it: it is too dangerous. Go to a gun shop and buy a few ounces.)
  • Melt it with sucrose and gently melt. Again, use very small quantities. Makes a good demo for solid rocket fuel. But it is too hygroscopic to make decent rocket fuel: there are better alternatives.
  • Heat it in a test tube until oxygen evolves. Do the demo with a smoldering toothpick.
  • Help stumps decay quickly.
  • Put it in the garden or on the lawn. It is 14-0-44 fertilizer, and the plants will love it.

See Freedom to Tinker.