Random Saturday night thought: How are Slinky's made?

[tridim]

No idea why this popped into my head, but it's got me curious.. I found the following at this website: http://www.engineerguy.com/comm/3757.htm

"The company uses the same machines that Betty's husband designed in 1945. No one has ever been able to build better machines. So important are they to making Slinkys, that no one is ever allowed to photograph them, for fear foreign competitors could copy the machines and bootleg Slinkys.

The machines make a slinky in about ten seconds by coiling a sixty-three foot metal wire into eighty-nine coils. When finished the machine drops the slinky which pops up, walks down a step, and steps into its own box. This isn't just for fun. A slinky wound too tight or too loose won't walk down the step and into the box correctly, and are rejected."

The "step into the box" quality test has to be the coolest thing ever! Anyway, since it's a secret, anyone want to take a guess how they wind them? It doesn't seem like the wire (which is flat) would bend very well via normal methods at room temperature. I would think it would tend to crack and curl on the outside edge. Any ideas?

[Tallison]

1. I don't know, but good question

I wonder about how many things are engineered, but lack the quantitative skill to appreciate the process of most.

[Elidor]

2. Heat it slightly and stress one side

Like when you pinch a strand of hair between two fingers and pull along it's length. That is pretty cool, the step into the box.

[Gregorian]

3. Wow. Thanks.

That is not the story I had been told. Glad to know what really happened.
And the weirdest part about your post is that I spent some time talking with my dad today about the process of inventing. It is my experience that inventing is often little more than discovering. Just observing something. I mean that inventions actually invent themselves, sort of. :)