According to The Machinery's Handbook, 27th ed., the margin of error for tightening screws 'by feel of hand' is +/-35%. Using a torque wrench has a margin of +/-25%, which in my mind is still substantial and is not a meaningful improvement over the 'by feel' method. So, is the significantly more expensive torque wrenches worth the price? If yes, why?
According to The Machinery's Handbook, 27th ed., the margin of error for tightening screws 'by feel of hand' is +/-35%. Using a torque wrench has a margin of +/-25%, which in my mind is still substantial and is not a meaningful improvement over the 'by feel' method. So, is the significantly more expensive torque wrenches worth the price? If yes, why?