Wire Gauge Over Time

[ChrisMinelli]

Hello,

 

If my 1952 Plymouth's service manual (printed in 1952) says, for example, "Green 12" I can replace the wire with a 12 gauge green wire from today without having to translate the size?  In other words, a 12 gauge wire in 1952 is the same as a 12 gauge wire in 2020, right?

 

Thanks!

[Plymouthy Adams]

wire gauge is the conductor not the insulation...some insulation depending of composition ranges from thin to fairly thick making it look larger than the actual size....

[desoto1939]

I would think that based on Plymouthy reply that we really do not know the gage of the wire because of the outer covering thickness.  I always assumed that when they wrote 12 ga 10 gage wire that the inner stands of the wire is the size that they were referring to and did not include the outer wrapping in the size.  So how do we determine if the size is correct?

 

You would have to open the package pull out some wire strip off the cover and then measure the wire.  I do not think some of the stores would appreciate us doing this to their packages. 

 

I am  assuming that the labeling is referring to the gage of the stranded wire alone and not the wire and the outer cover being include in the gage of the wire.

 

Just food for thought.

 

Rich Hartung

[Dodgeb4ya]

A lot of wire today is chinese.

Some of it is not as thick as the gauge it's supposed to be.

I have found this to be true when

re wiring one of my trucks...

If concerned about wire conductor size buy a wire gauge tool to check the conductor size...wire strippers can give you an idea but are not a gauge tool.

[desoto1939]

I just did a wiki search on how to officially determine the exact size of a stranded and solid wire when it is covered in a plastic outer covering.

 

Use the link below to get a better understanding of wire;

 

very interesting topic.

 

https://www.wikihow.com/Gauge-Wire

 

Rich Hartung

desoto1939

[ChrisMinelli]

To be more specific: if I need 10 gauge wire according to a book from 1952, can I buy 10 gauge wire in 2020 and assume that is what they are talking about?  Thanks!

[Merle Coggins]

I work with European wire diagrams daily and often see the wire size listed in cross section mm2. I use a chart like this to cross it to the AWG wire gauge sizing.

[Merle Coggins]

7 minutes ago, ChrisMinelli said:

To be more specific: if I need 10 gauge wire according to a book from 1952, can I buy 10 gauge wire in 2020 and assume that is what they are talking about?  Thanks!

 

Yes. wire gauge sized haven't changed

[Sniper]

Wire sized ratings are by the diameter of the conductor, not the insulation.  Insulation material choices have substantially changed since our cars were built.  The insulation should be sufficient to electrically insulate the wire and depending on the application handle various temperatures (-40 to 80 degrees C), chemicals, abrasion and flame.  Back in the day who knows.    SAE-J1128 GPT calls out the minimum specs today, but it was first issued in 1975 and has been updated several times since.  Attached is a spec sheet with various data points, including conductor diameters. 

PD373407-AN.PDF

[Eneto-55]

In looking for wire sources some months ago (still haven't ordered any - haven't figured out exactly how much of each size & color I will need yet) I saw reviews on some of the cheaper wire sources saying that the gauge listed on a lot of wire coming out of China is more or less approximate, generally smaller than claimed.  So, get the higher priced wire if you want to be more confident in what you are actually getting.

 

About the two numbers - Isn't one of the numbers to do with the number of strands (fine vs coarse)?

 

Edited to add:  I see now that the chart Sniper linked to has the strand count info listed as well.

Edited February 12, 2020 by Eneto-55
add note

[Dodgeb4ya]

☆It is true some imported wire is not the gauge as stated on packaging☆..

Sad but true...best to size check it if you're concerned.

Edited February 12, 2020 by Dodgeb4ya

[Sniper]

You can buy cheap wire, or not cheap wire and we aren't talking price. 

 

I have a friend that is an insurance investigator and he has found that there is a certain country out there that counterfeits UL listing and such.  That is one of the cheap wire sources. 

 

I would source US made wire myself. 

[greg g]

And who knows what the metallurgy of the offshore wire is and what it's resistance is per given length.  Just enough to copper to color the recycled tuna cans to make it look like copper.  If yer gonna err on wire gauge for 6v go next size bigger.

Edited February 12, 2020 by greg g

[Pete]

These may or may not help.

 

Pete

 

 

Mopar wiring code information.pdf Guide to Wire and Fuses.pdf

[Ulu]

I got caught on this one...

My daughter called me to help her jumpstart her car.

When I got there she was doing fine but the engine wouldn't crank.

I started fiddling with the clamps, and something felt funny. I took a good look at the wire.

The cables she bought had only 12 ga copper (maybe real copper, maybe...?) in a plastic cable that looks like 4 gage!

I grabbed the clamp and pulled it right off the wire. not even well crimped!

 

"Where did you get these, sweetie?"

"Ummm . . . Home shopping club." <sheepish daughter look>

 

I took her to NAPA and bought her some real cables. 

 

[greg g]

But at least she grasps the concept of jumper cables.  That's more advanced then a lot of my daughters male friends.

[desoto1939]

1 hour ago, Ulu said:

I got caught on this one...

My daughter called me to help her jumpstart her car.

When I got there she was doing fine but the engine wouldn't crank.

I started fiddling with the clamps, and something felt funny. I took a good look at the wire.

The cables she bought had only 12 ga copper (maybe real copper, maybe...?) in a plastic cable that looks like 4 gage!

I grabbed the clamp and pulled it right off the wire. not even well crimped!

 

"Where did you get these, sweetie?"

"Ummm . . . Home shopping club." <sheepish daughter look>

 

I took her to NAPA and bought her some real cables. 

 

I just attended the Antique Automotive club of America annual convention and lecture series  in Philadelphia this past weekend.  Attend a lecture on car batteries. 

 

One of the points that this lecture pointed out is this:

When jumping a battery and the hood has been opened on both vehicles you should wave your hand or used an object to make some air movement over the top of each battery to remove any sulphuric acid vapors above each battery prior to doing anything.

 

Then connect the proper cable to the dead battery.        Then go an connect the appropriate cable to the car that has the good battery and then start the jumping process.

 

everyone should remind their wife's and children and also you about this safety factor.  A lot of good information was provided about car batteries.

 

The lecturer even stated that the biggest difference that he has found between a 3yr and a 5 year battery is the amount of space at the bottom of the plates to the case bottom.  The 5 year battery has a great amount of space so the  plate material can then settle to the bottom and has more distance or thickness than a 3 year guaranteed battery.  Basically thy are the same but the amount of space at the bottom is the difference.

 

Also there are only 4 major auto battery suppliers but he did not tell us those companies.

 

Rich Hartung

desoto1939@aol.com