"RWL" wrote in message
...
On Sat, 22 Jan 2005 18:51:46 GMT, "Wayne Lundberg"
wrote:

Back when I was a practicing Mfg. Eng. at Solar Turbines I did extensive
research into deburring the inside hole made in tubing. I failed to find
anything really earth-shaking.

Perfect choice of words for the method I'll describe.

Anybody have any proven success with this kind of problem?

I was told about this by an old Swiss toolmaker who described it to
me. I never saw it in action. They needed to deburr some copper
parts they were making. They made up something they called "the
bomb". Essentiallly a big metal box. They put the parts inside along
with fuel (gasoline?) vapor and touched it off. The flash burned off
the burrs. We live in a pretty rural area and his business was way
back in the woods where most people didn't know it existed. In the
60's (I think that was the era) he was making parts for the cameras in
the U2 spy planes. He had to work to precision somewhere in the
millionths. The shop is across the river and about a mile from a
railroad yard as the crow flies. The trains induced vibrations in the
work which kept him from getting the precision he needed. He had to
do the work in the wee hours from Saturday through some time on Sunday
since that's the only time they weren't shifting trains around. At
any rate, the method certainly was earth shaking. I can't prove he
wasn't pulling my leg, but I don't think so; he just didn't impress me
as being that kind of guy. He's been dead for a number of years now
so I can't inquire about the bomb for you. NO - he didn't die in an
explosion.

Bob Lamparter

I had the pleasure of working alongside Gil Cadwell who pioneered explosive
fabrication and several other methods for smashing thin sheet metals into
compound irregular shapes. One of them was the use of a sparkplug submerged
in water and detonated by a bank of capacitors that created such a huge
spark that the water was decomposed into oxygen and hydrogen and in that
millisecond exploded to create a miniature atomic bomb in the water. The
part itself was set next to a tool which received the now very plastic sheet
metal to form it perfectly. The first time they tested the idea the shed
blew up. Fortunately he and his crew triggered the explosion from some
distance. It became known as Hydroforming.

I don't think gasoline or a well combined air/gas mix would be hot enough to
evaporate the burrs from inside the aluminum tube. But it's worth thinking
about perhaps as an EDM.

You got me thinking!