Great video presentation, much better than any episode of the How It's Made
TV show that I've seen.
Fire, and lots of shop-made metal parts to be observed. Resistance spot
welding and induction heating, too.

It looked as though the equipment he was using was all shop-made, and at the
end of the video, it shows the guy making parts in a well equipped machine
shop.

FWIW, and contrary to popular belief, contained vacuum doesn't have to be
performed by using a vacuum pump.
When a vessel is heated to a high temperature, it's fairly well evacuated of
air. Sealing the vessel/envelope while it's hot can be performed fairly
easily when the envelope is glass, whether it's a small vacuum tube or a
CRT.

A simple grade-school demonstration in the early 1960s involved dropping a
small burning piece of paper into a milk bottle, and placing a hardboiled
egg on top of the opening, as the flame went out.
That was a time when milk came in a heavy reuseable bottle with a large
neck.
Of course, this didn't demonstrate the evacuation process by external heat,
it was just fun to see.

WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


wrote in message
...
Pretty interesting vid if you have about 17 minutes to kill.

http://blog.makezine.com/archive/200...ccum_tube.html

Dave