document updated 14 years ago, on Oct 9, 2009
Basically, I want to teach a very short segment about how to avoid stripping screws. There are a lot of people who have almost no experience with unscrewing tight screws, and they tend to mangle our screwdrivers at a pretty high rate.
Some exercizes I've considered:
break loose a bolt
The student would be given an already-tightened bolt, a wrench, and asked to loosen the bolt. They would be asked to pay close attention to how to it feels when the bolt first begins to turn, when it's at its point of highest pressure from the wrench. And then compare that feeling to fully loosening the bolt.
SETUP:
- the bolt should be inside a board with the threads embedded in some way (eg. if it's in a wooden board, there would be a nut that's sandwiched between two boards)
- the wrench should be cheap
- a simple wrench would work, if the nut-head was hexagonal
- can we get the bicycle-style bolts though, that let you use an allen wrenches with them? That would be more intuitive to students.
- the "board":
- Unfortunately, it can't be wood. The feeling we're going for is the one they feel when working on computers, and THAT has a sharp transition right when the bolt breaks loose. Wood doesn't have nearly as sharp of a transition, because wood compresses.
- Metal
- A piece of thick-walled conduit isn't too expensive. Holes could be drilled through the center, and a metal bolt affixed to the other side.