# Where do all those funny 'standards' come from

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We got into a discussion of all the metalworking and related standards: a mile is 1000 Roman Soldier paces, standard train track gage is from the Roman chariots. The various sheet metal and wire gages are mostly based on weight per square foot of the number of sheets. Letter drill sizes are just the odd sizes needed in between fractional sizes. shotgun gage is number of round lead balls per pound. Pipe sizes are the minimum inside diameter of standard pipe wall thickness.

But where do the screw sizes from 0 to 14 come from? #12 is pretty much

3/16" but the others????
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The size of # screws has been discussed before in this forum.

In a nutshell, a # 0 screw is .060" diameter, and starting from there each one # increment increases the screw diameter by .013".

Consequently a # 5 screw's dia. = (5 x .013) + .060 = .125" dia. A #10 screw is (10 x .013) + .060 = .190 " dia.

Actual screw sizes are a few thou. smaller in diameter than the calculation gives to ensure the screws fit into nominally sized holes.

Wolfgang

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Musta bin tall fellows to have a 63 inch pace!

standard train track gage is from

#10 not #12

is pretty much

0.06 + #x .013 Gerry :-)} London, Canada
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I get 6048 furlongs per hogshead with my Ford van. What a great sales point!

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Here's a couple of screwy stories.

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Thanks for the links! I'm supposed to do a talk on standards this afternoon, gives some nice stories to tell.

Stupendous Man wrote:

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This has a brief reference to the origin of the American "Briggs Pipe Thread" or BPT standard. If you can get to the report at all, it's on page 281.

Jim Wilkins

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I missed the Staff meeting, but the Memos showed that RoyJ wrote on Wed, 22 Oct 2008 10:04:00 -0500 in rec.crafts.metalworking :

Well, let us know how it turned out.

One of the interesting questions I have is "how" did this standard get set. Numbered drills are one. Wire gauges. I know that nails used to be sold as "the weight in pounds of a thousand, expressed in pence" (and abbreviated 'd' for 'denarius'), but what makes a #2 screwdriver a "#2"?

And L/S/D? Twelve pence to the shilling, but twenty shillings to the pound?

-- pyotr filipivich "I had just been through hell and must have looked like death warmed over walking into the saloon, because when I asked the bartender whether they served zombies he said, ?Sure, what'll you have?'" from I Hear America Swinging by Peter DeVries

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I missed the Staff meeting, but the Memos showed that Gerald Miller wrote on Wed, 22 Oct 2008 00:41:29 -0400 in rec.crafts.metalworking :

"Left, right " is a "pace". As in "step forward one pace" is to step forward with the right foot, then with the left foot, and bring the right foot up stop. So a "pace" is every time your left foot comes back down.

That makes a good story, but ... I'll agree to the concept.

-- pyotr filipivich "I had just been through hell and must have looked like death warmed over walking into the saloon, because when I asked the bartender whether they served zombies he said, ?Sure, what'll you have?'" from I Hear America Swinging by Peter DeVries

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Ah, but how did a .060 inch screw become known as a #0 Screw?

-- pyotr filipivich "I had just been through hell and must have looked like death warmed over walking into the saloon, because when I asked the bartender whether they served zombies he said, ?Sure, what'll you have?'" from I Hear America Swinging by Peter DeVries

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I missed the Staff meeting, but the Memos showed that RoyJ wrote on Tue, 21 Oct 2008 22:42:38 -0500 in rec.crafts.metalworking :

How many gallons to a barrel? depends on whether its a barrel of oil, or wine. Or flour.

-- pyotr filipivich "I had just been through hell and must have looked like death warmed over walking into the saloon, because when I asked the bartender whether they served zombies he said, ?Sure, what'll you have?'" from I Hear America Swinging by Peter DeVries

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Comparison of Stub's steel wire gage and numbered drill series:

A = gage/index number B = Stub's *steel* wire gage diameter (in) C = standard numbered drill diameter (in)

A B C

1 0.227 0.2280 2 0.219 0.2210 3 0.212 0.2130 4 0.207 0.2090 5 0.204 0.2055 6 0.201 0.2040 7 0.199 0.2010 8 0.197 0.1990 9 0.194 0.1960 10 0.191 0.1935 11 0.188 0.1910 12 0.185 0.1890 13 0.182 0.1850 14 0.180 0.1820 15 0.178 0.1800 16 0.175 0.1770 17 0.172 0.1730 18 0.168 0.1695 19 0.164 0.1660 20 0.161 0.1610 21 0.157 0.1590 22 0.155 0.1570 23 0.153 0.1540 24 0.151 0.1520 25 0.148 0.1495 26 0.146 0.1470 27 0.143 0.1440 28 0.139 0.1405 29 0.134 0.1360 30 0.127 0.1285 31 0.120 0.1200 32 0.115 0.1160 33 0.112 0.1130 34 0.110 0.1110 35 0.108 0.1100 36 0.106 0.1065 37 0.103 0.1040 38 0.101 0.1015 39 0.099 0.0995 40 0.097 0.0980 41 0.095 0.0960 42 0.092 0.0935 43 0.088 0.0890 44 0.085 0.0860 45 0.081 0.0820 46 0.079 0.0810 47 0.077 0.0785 48 0.075 0.0760 49 0.072 0.0730 50 0.069 0.0700 51 0.066 0.0670 52 0.063 0.0635 53 0.058 0.0595 54 0.055 0.0550 55 0.050 0.0520 56 0.045 0.0465 57 0.042 0.0430 58 0.041 0.0420 59 0.040 0.0410 60 0.039 0.0400 61 0.038 0.0390 62 0.037 0.0380 63 0.036 0.0370 64 0.035 0.0360 65 0.033 0.0350 66 0.032 0.0330 67 0.031 0.0320 68 0.030 0.0310 69 0.029 0.0292 70 0.027 0.0280 71 0.026 0.0260 72 0.024 0.0250 73 0.023 0.0240 74 0.022 0.0225 75 0.020 0.0210 76 0.018 0.0200 77 0.016 0.0180 78 0.015 0.0160 79 0.014 0.0145 80 0.013 0.0135

A linear polynomial fit (with correlation 0.997) to these data yields:

diameter = A0 + A1*N

where:

A0 = 0.224840 A1 = -0.003150

and N is the drill number

240 silver pennies (Latin denarius from whence the "d") weighed a pound (Latin libra from whence the stylized letter "L" pound symbol). The shilling corresponded to the Latin solidus or 12d.

Regards, Marv

Home Shop Freeware - Tools for People Who Build Things

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It's size- the same thing that makes a #1 phillips a #1.

does it even matter though? I can cross any ocean ask for a #3 phillips and nobody will be confused. That's a great standard- people agreeing on what something is. The numbers behind it don't have to have pretty values or meanings.

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Sure, it's a trivia question, but some trivia questions are interesting. This strikes me as one of them.

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Is this one as fun?

Why is "red" called "red" and not "green"?

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And let us not forget the crown, of which 4 to the pound,

and its child the half-crown, 2/6, not to mention the florin coming in at two shillings, 2s. or 2/-.
For the non-PC amongst us, may I offer the guinea at one pound and one shilling, £1/1/-, commonly used for buying horses or as stakes in horse- racing, eg. the "1000 Guinea Stakes"
You can't say English is boring - altho' I have heard other epithets applied.

Mike in BC

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I missed the Staff meeting, but the Memos showed that Marv wrote on Wed, 22 Oct 2008 17:53:43 GMT in rec.crafts.metalworking :

Ah, I knew there had to be a logical reason.

pyotr

I also know that "It made Sense at the Time" is often considered a logical reason as well.

-- pyotr filipivich "I had just been through hell and must have looked like death warmed over walking into the saloon, because when I asked the bartender whether they served zombies he said, ?Sure, what'll you have?'" from I Hear America Swinging by Peter DeVries

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Why are blackberries red when they are green.

pyotr

-- pyotr filipivich "I had just been through hell and must have looked like death warmed over walking into the saloon, because when I asked the bartender whether they served zombies he said, ?Sure, what'll you have?'" from I Hear America Swinging by Peter DeVries

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That's left foot _plus_ right foot (double pace). It's about right for me and I'm 5' 4"

Mark Rand RTFM

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