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Using Solidworks FEA, I decided that this cross-section worked under the following conditions:
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The FEA was set up with the face that contacts the forward closure fixed. The 4330 lb force is acting upward on the top surface of the bolt holes and 960 lb shear force acts radial outward on eaach each hole to simulate the bolt teniontension. The safety factor is 2.27.
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