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Thanks for the metallurgy treatise. If it is 6061 and this is hardenable (I agree with the logic that says it would not have been tempered after forming since this would add cost and steps that are unecessary), then I would suspect that this is part of the reason they are failing. The highly stressed parts work and age harden, get brittle and snap when the boat gets tossed sideways once too often. I've snapped 2 of them so far so can attest to the fact that they do get heavily stressed. I would have thought he would have used pure aluminum 3003 to avoid work hardening embrittlement. But looking at the breaks, it looked fairly crystalline, possibly why the the welder thought it was cast aluminum, but hardened brittle aluminum might be the reason for the brittle break appearance.

Hello:
Just FYI. The replacement brackets I received for my 95 model were actually stamped, put on the break and then welded. I had to deburr both parts and have them re-anodized. Also, the fulcrum arm length is different so the steering relationships changed.