On Thu, 17 Jul 2008 05:46:17 -0700, Larry Jaques
wrote:


Soooo, what kind of tooling will make that kind of winding, Ned?
Those must be expensive lamps to warrant the extra steps of dissolving
the steel core, neutralizing the acid, etc.

The first coiling on the mandrel is made by the spool by a machine
like this.
http://www.yiwon.co.kr/pcm008(e).htm

There are any number of ways to make the second coiling. High volume
filaments are made on dedicated high speed machines. Heavy low volume
coils like that in the pic are often made on spring winders, which are
general purpose wire forming machines. In addition to making plain
coils, they can be tooled to form all sorts of ends on the coil.

All coiled-coil filaments, even a $.50 standard 60W bulb, are made on
mandrels. The steel is dissolved out in hot HCl. But you're right, the
neutralizing and washing is critical.



I think the pic
is there to demonstrate what sort of photos can be taken with a cheap
digital camera and a stereo microscope.

Cool. What's the actual size?

The small wire is about .005, the overall diameter is about 1/8".


I like offbeat work like that. I've recently put up a teepee for one
client and bid on repairing a broken casket for another.

I lived in a teepee for a while, erecting one properly isn't easy. I
turned down some work at a large casket manufacturer several years
ago. Besides the fact that it was farther away than I prefer, building
furniture to be buried rubbed me the wrong way.

--
Ned Simmons