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Torque wrench graduation markings

21K views 9 replies 5 participants last post by  barneys  
#1 ·
I have just bought a new torque wrench and have a question about the graduation markings on the barrel. One set is headed ft lbs Which I am Ok with. The other is headed M Kgs, which I although reversed, is Kilograms Metres. What I don't understand is above this scale it is marked (da N.m). What does that mean?
 
#4 ·
I realise that Nm is Newton Metres. What I can't understand is why the legend (da Nm) is immediately above the Kilogram Metre scale. I didn't think Nm & Kg M were the same, at least not according to the conversion chart supplied with the wrench.
 
#5 ·
Hold on to your hats. Here comes the Physics.

The kilogram is a unit of mass. The Newton is a unit of force.

From your schooldays, you may remember:

Force = Mass x Acceleration​

where the acceleration 9.81 ms^-2, which is approximately 10.

So 1 Newton = 10 kg and 1 kg = 0.1 Newton

What it boils down to is that 1 kilogram meter is roughly equivalent to a tenth of a Newton meter, which can be abbreviated to 1 deci (not Deca) Newton meter.

Brit twin had the right idea, but the wrong way round. :p