Knock Off Spinner Tool

[ItBites]

Tbuttrick,

I'll add that the thread diameter on the F1 car in your picture appears much smaller in diameter than the usual Cobra setup, so it would need less torque than a Cobra, but even so, with a 3 foot wrench, it is not that hard to produce a bunch of torque with a 'yank' from a single arm. Still would be less than a large diameter Cobra knock-off would need...

As far as the Olthoff video, two things to consider. The amount of force a hammer produces, when swung and then stopped in a short distance is huge. I could go into the equations of kinetic energy (KE = 1/2 x mass x velocity squared) being converted into force as it is decellerated (KE = Force x distance), but a quick inspection of the equations should convince you that when the distance gets small, the force gets very large. Further, during an impact shock, the friction (which drives the .2 constant in the torque equations above) is instantaneously reduced to a very low value. This means that a small 'constant' torque will tighten a festener adequately, if it is accompanied by a impact shock. These two things make the hammer method decieving in terms of thinking about an equivalent applied wrench torque and lead you to think a small wrench torque will achieve the same result.