Testing Torque Wrenches

[flippin]

Good Morning!

As a self-professed overthinker, should the torque tester available in most tool trucks be effected by drive size adapters? My Snap-On guy has a torque tester which he encourages me to use to quickly determine if a torque wrench should be sent in for calibration. The wall mounted meter is 1/2" drive. To test my smaller torque wrenches I would need drive size adapters. Should this make any difference. For bigger stuff, (1/2" to 3/4") I wouldn't be worried at all, but for the 1/4" precision stuff will I lose accuracy in measurement?

With appreciation,
-Paul

 

[country83]

No, accuracy is not affected by drive size adapters. What will affect it is on a smaller drive like the 1/4" you're talking about, it may not have the resolution of a dedicated smaller tester, for example if the tester only reads down to say .5 ft-lb increments, that would be fine for 3/8" or 1/2" drive, but that's a big increment on 1/4" drive. A smaller tester could easily go down to .05 in-lbs or better.

 

[flippin]

Thank you, kinda my thought, but with all of the threads about torque loss when using extensions and adapters my head was spinning.

 

[dnschmidt]

Had a recent experience rebuilding a friends Powerstroke 6.0 diesel engine. I printed out the torque specifications for all of the fasteners on this engine which is big, powerful, really heavy and all cast Iron and amazingly 95% of the fasteners used on this beast are torque specified under 50 N-m. I used a 1/4" drive torque wrench for a lot more fasteners than I used my big assed 1/2" drive 400 N-m torque wrench which was only needed to achieve the 210 ft-lb specified for the ARP head studs we installed. I FOUND THIS REMARKABLE.

 

[bb29510]

why?

 

[2ndGearRubber]

Had a recent experience rebuilding a friends Powerstroke 6.0 diesel engine. I printed out the torque specifications for all of the fasteners on this engine which is big, powerful, really heavy and all cast Iron and amazingly 95% of the fasteners used on this beast are torque specified under 50 N-m. I used a 1/4" drive torque wrench for a lot more fasteners than I used my big assed 1/2" drive 400 N-m torque wrench which was only needed to achieve the 210 ft-lb specified for the ARP head studs we installed. I FOUND THIS REMARKABLE.

Most stuff.simply doesn't require the clamping force. 50nm is like 35ft/lbs.

Things like gaskets surfaces, water pumps, accessory drives don't see massive clamp loads required based on application. Most hardware on an engine is m10 and smaller. M6 is rarely above 10ft/lbs, m8 above 25, m10 above 50. There are obvious exceptions like internal engine fasteners. But generally your generic 10.9 bolt on an engine will follow those caps.

Remember too, that high cylinder pressures of a turbo diesel is only cylinder pressure. The belt tensioner just needs to not fall off.

 

[General Geoff]

Thank you, kinda my thought, but with all of the threads about torque loss when using extensions and adapters my head was spinning.

Extensions and adapters that don't change the axis or radius of applied force from handle to fastener do not affect the torque output of hand tools. These only rob torque from impact wrenches.

 

[flippin]

This is perfect, thank you for the clear explanation. Makes sense.

 

[oldschoolcraft]

How do you ensure the calibration test fasteners maintain their calibration?