New Mast Tangs

[Roger Long]

Wouldn't the ultimate breaking strength of the shroud normally be less ...

Chainplates are usually considerably stronger than the wire. They go down into places were water can get in and sit, they are hard to replace, and their weight isn't especially critical.

Industry standard, conventional tang design is pretty crappy as we've learned in this thread. Tangs are usually stronger than the wire but not by as much as the chainplates.

If you overstress a brand new production boat rig, it would probably be the wire that let go.

If you overstress an old production boat rig, it will probably be a swaged fitting.

If you put new rigging on an old production boat, it will probably be a tang that breaks first.

 

[Ron20324]

Roger, how long did the present tangs last, and are they the originals?

 

[Roger Long]

Roger, how long did the present tangs last, and are they the originals?

I'm pretty sure the tangs and rigging are original because the boat came from Detroit and rigging is almost never replaced in that part of the world due to the fresh water and short seasons. The boat is 1980 but spent six years laid up with the mast erected. She has been here in salt water since 2006.

The tangs look quite good and I expect that, after dye testing and checking, would probably last for the remainder of my life. However, when I'm in deep shit off someplace like Newfoundland, as I probably will be some day, I don't want the rig to be one of the many things I will be worrying about. New rigging, a couple grand, peace of mind, priceless.

 

[Roger Long]

I ran across some data sheets that have been following me around folded up in a book since I worked at Philip L. Rhodes in 1970. This portion is interesting. The lower shrouds do more work than I remembered so all the numbers above for my uppers should be very conservative.

I'm not sure why the loads add up to 110% but it's close enough.

 

[tommays]

That would explane why the Cal has much bigger lowers