4000 meters 48 - 49 AWG GE Tungsten Wire Fine

4000 meters 48 - 49  AWG GE Tungsten Wire Fine

Shipping From 32934

      Description   

• This auction is for a .0012" OD wire, length 3984.74  meter spool of Tungsten wire.  I came across this as I was cleaning up.  The business I was in did work with fine wire, however, we usually didn't use wire this fine.  By the date on the spool 11/14/91,  I can only take a guess as to why I have this.  During that time period I personally was involved in a large scale programming project for GE while other engineers in our firm were involved with a project that involved using very fine wire for testing a machine they were developing (It never got pass first base).  The machine basically caught the wire on a highly polished finger, wrapped it (the wire) around a couple of needles about 10 inches apart for about 10 loops, then the needles spun and also came closer together to form what was called a skein. The wire could then be wrapped automatically around a pin on a bobbin without fracturing or cutting the wire.  From what I know of the project probably no more then 1 or 2 test with this were ever performed.  
  
   

• This will ship via priority mail in a box.  It will be wrapped in tissue paper to prevent any damage.  I suggest purchasing insurance. (However in all the years we have been doing shipping, over 40,  we have had only 1 claim and it was with a carrier other then the US Post Office.)
   

•  If I use the .0012" measurement that is on the spool the math comes out with 3984.74 meters and a diameter of  39.80.  The .0012" measurement was taken with a laser micrometer and should be accurate.  The rest of the measurements were taken with the instruments I have today and they are only accurate to .001 maybe .0001 at best.   After I have done some research as to why I have this I found that this is probably a #38 SWG or Imperial Standard Wire Gauge which would make this .0012".
   

• I was asked what this wire is used for so I did some research into the uses of this product.  It uses back in the mid 20th century made this more valuable then gold, however with advent of the digital age the old style vacuum tube has gone by the wayside as has many other advances in science.  Its usage as a light source is still important, but that too is probably going to dissolve into oblivion.  The two main properties that this wire has is its strength and the extremely high temperature it can withstand.  GE took the mystery out of extruding Tungsten into such a fine wire back in the late 1940s, but it is still a long drawn out process from what I understand.  I also understand it uses are getting more and more limited, which will make this ever more valuable as it will probably not be profitable to make in any quantity.
   

• I took a picture of .001 micrometers measuring the OD of this wire (see below). They still give you a good indication of the wire size.  If you look close you should be able to see the wire going through the caliper section.  I would say this is 49AWG but when I do the math using that size wire I come out with more wire on the spool then the label says there is. 
   

• Using a  gram scale this weighted 68.2 grams.
   

• This is sold as is (No returns on this item due to its nature).