Tightening Screws

[rgmwa]

I feel like this is a dumb question, but is there any requirement for torqueing #6 and #8 screws to a particular value, or is it just a case of 'it feels about right' ?

There is plenty of information about torqueing ANxx bolts, but I haven't been able to find anything about screws. I'm not sure how you would measure screw torque anyway, as the values would be very low.

An example are the screws and locknuts that secure the Ray Allen servo to the tray.

 

[terrye]

Screw torque

Short answer: No.
Long answer, "that feels about right" is not very accurate either. Studies have shown that mechanics tend to overtorque 3/8" bolts and under, and undertorque those over 3/8".
So to calibrate your arm, you could try sacrificing some #6, #8, -3 and -4 screws and bolts just to see what breakage torque feels like. Screws/bolts will take at least 75% of breaking torque in normal service and this is a good tightening value. Keep in mind that the screwdriver may slip out of the screw head prior to achieving this torque.

 

[GDS]

I tighten screws using the lowest torque setting on my Makita electric drill , haven't lost one yet.

 

[rgmwa]

Thanks guys...

Sounds like either the 75% Calibrated Arm or the Makita Mechanical Twist method will do the job