Tool sizes? Crossover? Any charts?
 

I just got an interesting e-mail from a friend. He mentioned that there are many sizes of tools where metric and SAE are the same. I guess we all now 19mm and 3/4" work this way. His question was if anyone has printed a chart listing this...if so, he'd be glad to buy a sticker he could place on a toolbox. So, is there such a chart or table? I replied that if there was, John or Warren would know about it...:)

There are sizes that are close...but not really the same becareful of using the SAE sizes on tightened nuts/bolts because they do have a very good chance of rounding the head/nut...usually on the metric its either a little under the same as the SAE or a little bigger than the SAE and vice versa...
I know I found out the hard way when I was younger :P.

I know a few off the top of my head that I just used...

3/8...10mm
1/2...13mm
9/16...15mm
etc...

Paul,

There aren't really that many in common fastener sizes ...

1-7/16" = 36 mm ... oil lines

1-3/16" = 30 mm ... early axle nuts

13/16" = 21 mm ... Nothing made in SAE works as well as the Klein 21 mm spark plug wrench in early OEM tool kits!!!

3/4" = 19 mm

Others that are close, but always are dependent on fastener AND wrench tolerances:

11/16" ~ 17 mm

9/16" ~ 14 mm

1/2" ~ 13 mm

7/16" ~ 11 mm ...<b> Highly Critical hydraulic fittings on brake lines where Precisely-fitting Flare-nut Wrenches are REQUIRED!!! DO NOT use loose-fitting flare-nut wrenches!</b>

5/16" ~ 8 mm

It's just arithmetic, 1"=25.4mm...

use common sense, no 12pts w/ poor fits, etc...

1/32" = 0.79mm
1/16" = 1.59mm
3/32" = 2.38mm
1/8 " = 3.17mm
5/32" = 3.97mm
3/16" = 4.76mm
7/32" = 5.56mm
1/4 " = 6.35mm
9/32" = 7.14mm
5/16" = 7.94mm
11/32" = 8.73mm
3/8 " = 9.52mm
13/32" = 10.32mm
7/16" = 11.11mm
15/32" = 11.91mm
1/2 " = 12.70mm
17/32" = 13.49mm
9/16" = 14.29mm
19/32" = 15.08mm
5/8 " = 15.88mm
21/32" = 16.67mm
11/16" = 17.46mm
23/32" = 18.26mm
3/4 " = 19.05mm
25/32" = 19.84mm
13/16" = 20.64mm
27/32" = 21.43mm
7/8 " = 22.22mm
29/32" = 23.02mm
15/16" = 23.81mm
31/32" = 24.61mm
1 " = 25.40mm

excuse the uncommon thirty-toooths, the one liner program didn't know any better

I have a 25/32" socket...totally useless unless I'm near a 727!