Wire gage debate

[mklotz]

I wanted to see if you were awake.

In the Imperial world we denote wire sizes by impenetrable gage numbers. There are at least a dozen different systems of gage numbers in use here and in the UK. In most of these systems the wire diameter decreases as the gage number increases (for convenience, don't you know).

However. for music wire the diameter increases with increasing gage number.

In an effort to eliminate this obvious source of confusion, the ASME (American Society of Measurement Exasperation) has decreed, that, henceforth, music wire diameters will be denoted by the musical note they play when twanged. This new gage, known as the NABP (North American Banjo Pluckers) gage will require every metalworker to carry a calibrated pitch pipe to blow when selecting wire. To simplify designation, constructions using several sizes of wire will by known by the tune they play when the wind blows over them.

 

[dsquire]

Marv

Do you have a program on your site that will help to decipher the tunes created by the vibs from the wire projects we create? :hDe: :hDe:


Cheers *beer*

Don

 

[Lew_Merrick_PE]

In the Imperial world we denote wire sizes by impenetrable gage numbers. There are at least a dozen different systems of gage numbers in use here and in the UK. In most of these systems the wire diameter decreases as the gage number increases (for convenience, don't you know).

Marv,

First of all, it's gauge, not gage when speaking of wire and sheet dimensions.

The reason that there are different gauge values is that each material has a different Poisson's ratio. A 16 gauge sheet of metal has been reduced by rolling 16 times from a basic (usually 1/2 inch nominal) thickness. Similarly, a wire is reduced by drawing it through a die from a starting diameter that (historically, at least) was 1/2 in nominal diameter. If you overstretch the metal while doing this reduction in thickness or diameter, you build inclusions into the crystal structure that weakens it. That is what sets the maximum reduction you can get with each drawing-down of dimension.

This is why you have copper gauge, iron gauge, steel gauge, and even tungsten gauge scales. You can decimalize it, but you don't change it. It does not matter if you measure in inches, millimetres, or barleycorn, the progressions are the same and derive from Poisson's ratio!

As an aside, I was doing work for a company that was "all metric." They would specify 1 mm thick steel for their products. Their Chinese suppliers provided them with 1 mm thick steel -- it was zinc plated 20 gauge sheet plated an extra .0003 thick to bring it up to 1 mm thickness. In another instance, a different company insisted on a specific (metric) thickness. The rolling mill in China changed their settings to provide it -- and it was so strain hardened that you could not even make a 90° bend at 2*thickness inside bend radius without the sheet cracking!

Gauges are not a measure, per se, they are processes!

 

[mklotz]

Lew,

Thanks for yet another pedantic contribution, complete with pointless war story.

You obviously missed my point so I'll explain it, typing really slowly.

Maybe if you're working in a wire manufactory gage numbers make sense. But allowing such bass-ackward measures of convenience into the marketplace is the sort of idiocy that makes the American measurement system the mess it is. When people buy wire or sheet they want to know its thickness. Having to wade through a transformation of a counter-intuitive gage number to get what should be part of the product designation is pure nonsense.

Oh, and most dictionaries list "gage" as an alternate spelling of "gauge".

 

[Cedge]

Psssst....
Hey guys!! the original question was......"what size drill bit do I need for a M5 hole." I don't think he cares much about industry standards or measuring systems beyond getting a hole he can actually thread for....get this.... his home shop project.

Steve

 

[zeeprogrammer]

the original question was.....

Yeah...and I think he got his answer back at post #11. :big:

This is a great forum.

 

[Lew_Merrick_PE]

Lew,

Thanks for yet another pedantic contribution, complete with pointless war story.

You obviously missed my point so I'll explain it, typing really slowly.

Maybe if you're working in a wire manufactory gage numbers make sense. But allowing such bass-ackward measures of convenience into the marketplace is the sort of idiocy that makes the American measurement system the mess it is. When people buy wire or sheet they want to know its thickness. Having to wade through a transformation of a counter-intuitive gage number to get what should be part of the product designation is pure nonsense.

Oh, and most dictionaries list "gage" as an alternate spelling of "gauge".

And you prefer ignorance? Knowing why things work or don't work is the basis of our trades. When those in the electrical world purchase wire, they want to know what the current carrying (i.e. cross-sectional area and resistance per length) is, not the diameter. In that instance, your assertion is wrong. Similarly, if you are purchasing tie-wire, you need to know the strength and formability of it, not the diameter.

The gauge system was developed in England (Manchester and Birmingham in particular). It is a sensible system that provides us with a broad array of thicknesses without embrittlement that leads to failure. There is information useful to anyone who does design or makes things in knowing why such processes were developed. Where would we be today without Lowenhertz, Whitworth, and Slocomb?

 

[Tin Falcon]

What is needed is clear concise, relevant, answers and comments related to the question.Period.
I split this thread off the original because it went way off topic into an unrelated debate. If it keeps up it may be locked or deleted.

Tin

 

[johnthomp]

my method of makeing sure i got the right drill size for a tap is drilling holes in a large block of wood i have screwed to the wall marked on it m2 m3 m4 etc in divided sections in each section there is 3 corresponding drills to each size tap and the corresponding die hanging on a pannel pin hook infront of those so i dont have to think i just do the job with the same little section i have most of my tools and bits set up this way it looks like chaos but its organized chaos with a place for evrything and evrything in its place ;D
and as for the m5 question i use a 4mm bit when im stuck and just make sure ive cleared the hole out good and propper then tap with a little more tapping compound than usual to guarantee i got a full thread depth
hope this answeres your question fella
reguards john

 

[PhillyVa]

hmmmmm..... testosterone