Yes I admit it, I confess, I Love Wire!
A while back Alpha Wire announced the release of a new wire called Thermo Thin Hook-up Wire. Here is their announcement on e14 in case you missed it.
The announcement offered a free sample so I signed up. That was June 8th. Today two months later I received 2 FEDEX packages each containing 2 feet of Red Thermo Thin Hook-up Wire. Since I had forgotten about my request it was a really nice surprise. Did I mention that I love wire.
This is 22 gauge Thermo Thin wire and it has 19 strands of 34 gauge wire covered by an ECA flouropolymer insulation that is rated at 600 volts. The insulation is quite flexible and can deal with a temperature range of minus 150 degrees C all the way to +300 degrees C. The excellent qualities of the insulation keep the external diameter of the 22 gauge wire to approximately 1 mm. One of the first things that caught my eye was how tightly the strands were wound. As close as I could figure it out we see a 360 degree twist for every cm. This gives the wire a lot of extra flexibility as the single strands are slightly helical and can flex without being stretched beyond their ability to recover or suffer damage. I have no test equipment capable of testing the claims of the manufacturer but I see no reason to doubt them.
Here is a link to Thermo Thin wire on Newark Electronics:
http://www.newark.com/alpha-wire/2922-bk005/hook-up-wire-22awg-black-30-5m/dp/22AC3402
I really wish I had a good application for this wire at this time. I can see that it would be a pleasure to work with compared to the stiff Teflon covered wire we used to use on sterilizers and other heat intensive equipment in the dental equipment field.
While we are on one of my favorite subjects I want to continue to talk about some of the wire technologies that have a special place in my heart.
The next one is the wire that was used in the coil cords of corded telephones. For those of us who spent most of our lives using corded phones it has to be a surprise that with all the use and all the abuse the coiled cords almost never failed. They could be stretched, pulled, swung and pulled between ones toes while simultaneously scratching the back of ones neck and continue to function properly for decades. In case you ever wondered why here is the secret.
Each of the 4 wires of the coiled cord had its own 4 separate conductors. Each of these conductors consisted of a nylon string with a flat ribbon of copper conductor wound around it like a coiled spring. If you look at the picture you can see where I have separated the copper ribbon from the inner nylon string on one conductor. Remember how impressed I was with the tight winding of the Thermo Thin with 1 twist per cm, well the phone wire has upwards of 15 coils per cm. In this configuration the wire is very much like a coiled spring and our bending and twisting has little or no effect on the copper conductor at any point. The internal nylon string takes up all the linear force and leaves the ribbon of copper to do its job of conducting electrons. One of the products that I developed for the dental industry used this technology to solve a problem. In the dental clinics there were wall mounted x-ray units to take radiographs of the patient's teeth. Each of these units had a coiled cord with a thumb switch attached so that the operator could step out of the room, away from the x-ray radiation, and push the button to make the exposure. These cords were very prone to failure and were constantly in need of repair or replacement. My re-purposing of telephone technology brought the telephone cord into the dental operatory to be used as the cord on these x-ray exposure switches. These cords are still being sold to dental equipment repair people across the world.
http://www.chapmanhuffman.com/index.php?main_page=product_info&cPath=7&products_id=461
Another of my favorite wires are the rubberized (silicone) test probe and patch cord wires made by Pomona. These 18 gauge beauties just call out to me and beg me to make them into test leads and patch cords.
They are composed of many small gauge strands (192 strands of 41ga according to the data sheet) that make them flexible and durable. I have lived long enough to know that the rubberized insulation will eventually ( 40 years or so ) harden and crumble but no one would be disappointed in this kind of a life span and perhaps the new silicone version will last even longer. In case you would like to make some nice cords for your own lab here is the link to the wire on e14 Newark Electronics. The Red is denoted by a -2 and the black by a -0. Just a side feature, (they smell nice too).
http://www.newark.com/pomona/6733-2/test-lead-wire-50ft-18awg-copper/dp/63H2515
Another of my pet wires is not to be found easily. I call them High Strand wire and I have only been able to get them by salvaging them out of expensive dental equipment cords. They are used in the cords that go between a table top machines and the handpieces used by the dentist. In some case they supply the 2 or 3 watts of power needed to light a small halogen bulb that lights the inside of the patients mouth. These wires can have up to a hundred or more individual strands of fine gauge wire all in a 20 to 24 overall gauge conductor. They are extremely flexible and durable. I like to use then in any application where I need to handle currents of up to an ampere and where the wire will under go a lot of bending and flexing. I would not use these wires for voltages over 30 or 40 volts as I am quite sure that the insulation is not rated for higher voltages. If you want to get a hold of some of this wire check with your local dentists and ask them to save their old handpiece cords for you or if you have a dental equipment repair man in your area he probably has a pile of them in a corner of his shop.
The last wire that I will cover here is the Kynar wire wrap hookup wire. I was reminded of this wire the other day when I read shabaz 's excellent DIY test instrument project:
If you look carefully at the first picture in his blog of the perf board prototype you can see how he has skillfully used the Kynar wire as hookup wire. It is very small diameter and can be threaded through the perf board holes to provide beauty and strain relief. The insulation on this wire is a cousin of the insulation on the Thermo Thin and as such is quite high voltage and tolerant of heat, cold and chemicals. Here is a picture of a 30 gauge Kynar wire:
Now that I have introduced you to some of my favorite wires I invite you to send me pictures and stories about your own favorite wire technology. When it comes to wires just remember that I am a little like a cat lady and your favorite might end up being part of my collection too.
John
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