Lou Messer, retired engineer here. Your cathead beam has the narrow dimension in the vertical plane, which has to carry a large fraction of the anchor weight. Beam stiffness is proportional to the depth to the forth power. (If you double it, it can carry 16 times the load. The width is going to waste in the horizontal plane. I woud advise abandoning catheads and going to a conventional bow anchor fitting.
Salt & Tar 
I am making four belaying pins for your cathead project. How can I get them to you?
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Hey Rocky! That’s so awesome. Shoot us an email 🙂
salt.and.tar@gmail.com
R
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Lou Messer, retired engineer here. Your cathead beam has the narrow dimension in the vertical plane, which has to carry a large fraction of the anchor weight. Beam stiffness is proportional to the depth to the forth power. (If you double it, it can carry 16 times the load. The width is going to waste in the horizontal plane. I woud advise abandoning catheads and going to a conventional bow anchor fitting.
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