Quote:
Originally Posted by djoutcry
Now I'm scared to use my jack stands...time to get some ramps...or install a lift in the garage
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Assuming a shear strength that is 75% of the ultimate tensile strength, and also assuming it being A36 steel (the most common grade around) at its lowest UST, we have 58 kPSI * .75 = 48.5 kPSI in shear. With a safety factor of 4 and a 3400 pound car that equals a load of 13600 pounds. 13.6/48.5 equals a .2804 in^2 pin to support the entire car with a 4X safety factor. That equates to a
single pin with a R.2988*2=Ø.5976 to support the vehicle (with a
4X safety factor
!!!.
I think there's more to this story than meets the eye.
I wouldn't be any more afraid of using jack stands than I would be a lift (which use
pins as a safety mechanism)