Jakelc15
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For do-it-yourselfers or the ones who can't buy them so cheap or aren't so close by....
I just did some comparative testing with my own creation of a "shear-pin cracker" (pat.pend. ) which actually worked better than expected.......
The OEM pins (including the broken core of my very 1st winch miss-hap...) snapped at about 160 ft-lb. More or less the same torque was needed for a home made one made of brass which I had used for years of "normal winching action" but later replaced when I found it with already some deformation.
Also I have a few larger ones of unknown application...(the M35 uses 0.279" x 2.125" measured inside cotter pin holes, these are 0.329" x 2.25") so I turned one down and it also took 160+ to shear it.
For comparison another "homemade" pin of unknown alloy but at least showing some temper... only resisted 100 foot-pound!
Next step will be trying to find 2024 or 2017 alloy locally and compare different levels of temper.
At least I know now what the goal is....
G.
By looking at your data above and I could be wrong but 160 lb/ft should yield about 45,000 psi shear strength. So you should be looking for 2024 in a t4 or t351 temper which has about 42,00 psi shear. The 6061 t6 only has about 30,000 psi and I recall reading that someone tried this for a shear pin and they thought it broke very easily. I am assuming that is a 3/4" bolt you are using since you have a 1 1/8" socket! I am also interested in making my own pins. My winch currently needs one and I have none. Would 5/16" round be what fits the M35 winch shear pin hole?