electrical milspec gurus

Let'sgoflying!

Let'sgoflying!

Touchdown! Greaser!
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Feb 23, 2005
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Dave Taylor
https://www.aircraftspruce.com/catalog/ (wire link)
Wow I wonder why the board doesn't like that link, let me try to bury it.
Here:

MIL-W-22759/16
I bought some of this (#2) and thought, well it's going to be copper with a shiny tin coating.
The cut ends have zero 'coppery' color and appear shiny silvery throughout.
It is either non-magnetic or low-magneticity (I don't have a compass handy)
Is it a copper alloy? Does it sound about right?
 
The MIL spec is actually cancelled and superseded by an SAE AS spec, AS22759/16. Part numbers remain the same.

AS22759/16 says: CONDUCTOR SHALL CONFORM TO AS29606 TYPE TCC SMALL DIAMETER TIN COATED COPPER CONDUCTOR FOR WIRE
SIZES 24 THROUGH 4 AND GENERAL PURPOSE FOR WIRE SIZES 2 THROUGH 00.

AS29606 (Which was formerly MIL-DTL-29606), Table 3 indicates that the conductor for type TCC is pure (unalloyed) annealed copper, with tin plating, per ATSM B965. Within ATSM B965, the copper specification is defined as ATSM B49, "Specification for Copper Rod Drawing Stock for Electrical Purposes", which is 99.90% pure copper.

There are other slash pages of AS22759 that do use alloyed copper, which has higher strength, but lower conductivity. The wire type should be marked on the insulation, might want to check that and see if you actually got what you ordered.
 
to me, the few pieces of copper wire I have seen in my brief life, they usually appear um....
-not silvery, but bronzy/coppery/slightly goldish in color

Just wondering why I am not seeing that on the cut ends of the wire (its a quarter inch across, thought that color would overwhelm anything else, including tinning, on the cut ends)
Could post a pic.
 
Let'sgoflying! said:
The website says

MIL-W-22759/16

The wire sheathing says, verbatim, including spaces:

M22759/16-2 27478 REV A
Click to expand...

M22759/16-2 is the correct part number, as listed in both the old MIL-W-22759/16 and the new SAE AS22759/16. 27478 is the CAGE (Corporate and Government Entity) code of the manufacturer, in this case Harbour Industries of Michigan.

http://www.harbourind.com/
 
I think I can explain...

Here's a piece of the same wire (except 16AWG).

IMG_20180801_194812.jpg

When I look at the end, I don't see anything but silver. If I put it under magnification, I can see some copper. But not much because the strands are mashed and bent over.

But if I sand down the end with some 400 grit...
1317764432706.jpg
 
awesome, don - thanks.
(like I'm gonna leave it at that.....out to the garage for my sanding block!)
 
BA9EC355-E24D-4514-88B8-7626943BFA46.jpeg

After grinding; slightly blurry, but obviously the color I’d been expecting and Don had explained...

59DBAA07-667F-41C0-8F3C-5C4F474001A6.jpeg
 
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