Aluminum Mast Repair

[Brion Toss]

Hello,
That is a very high-load area, and it has been highly-loaded for a long time. Tune, load amplitued, scantlings, and install quality might also have played a part in the deterioration. Aluminum is amazingly resilient material, but even it has its limits. I certainly would not count on stop-drilling here, as I've seen cracks leap right past the stops on more than one occasion, in similar circumstances. Welding seems also to be a very bad idea here. Short of a new stick, the best option might be to replace at least the top of the mast, with an internal sleeve. This is a heavy and stiff solution, but it's the only one I'd trust.
Fair leads,
Brion Toss