Square Drive Size vs Maximum Torque

[Dr.JohnnyFever]

The data below was allegedly gleaned from Hytorc's web site (though I cannot find it there). Is this reasonably accurate across quality tool brands? Is there a better source of data?

Drive size      Max Working Torque ft-lbs      Probable Failure ft-lbs
1/2"            385                            425
3/4"            1310                           1485
1"              3100                           3400
1-1/2"          10460                          11475
2-1/2"          48440                          53125

 

[rmsg0040]

I know that Snap On claims 700 ft lb on their 1/2 ratchets

http://image.snapon.com/international/pdf/sf80_slf80_shlf80_sx80_npa.pdf

 

[RGunner]

I do not mean to start a war (and please dont start one!). I have a SHLF80, there is NO WAY it can withstand 700 ft lbs of torque, it feels near break point at 1/3 of that.

 

[ChevyEFI]

Off topic, but can anyone direct me to what radial torque a press-fit relationship has, based on amount of interference fit?

 

[Veto]

If I was to use a 1/2" ratchet to reach 700 ft lbs of torque, I wouldn't be looking at a SHLF80 but more in the direction of the Facom S.161. Has 17 teeth engaged when tightening and can withstand 400kg on the handle of a 250mm ratchet.

It's pretty much the same as the Snap On claim but I would probably trust the Facom more due to the design, and if it fails it isn't as expensive as the Snap On.

 

[JJThrasher]

I've stood on my 24" 1/2" ratchet and I've sheared new 3/8" by hand. I think quality is more important than size.

Sent from my SCH-I535 using Tapatalk 2

 

[Biomed]

Is there a better source of data?

B107 series standards are published by ASME after approval by ASME and ANSI. B107.10-2005 is the standard for handles and attachments for hand socket wrenches - inch and metric series.

You can buy the standard online for about $60. I have never seen it freely available elsewhere.