are these strange back-stay brackets a weak link?

[dancamp009]

While examining my 45.7' spruce hollow mast I found these weird bracket connected to each other on the top of my one-and-only back-stay. Because the clevis pins in these two weird brackets are only 5/16" wide, while the other pin on top of the back-stay is 1/2" and the pin in the turnbuckle is 5/8" wide, I'm thinking these brackets are my weak link and perhaps should be removed. the 1 x 19 back-stay wire appears to be 5/16" or 12500 LBS breaking strength. I can't find the breaking shear strength of the 5/16" clevis pins holding these brackets to the wire. I've included two photos of these brackets and the back-stay below. The back-stay in the 2nd photo sits on top.
This gives me three questions:
1) Why are these two strange brackets on my back-stay?
2) Should I remove them and just extend the other short (2.5' +-) wire on top of them to make up the difference in length?
3) And, what is the breaking strength of SS 5/16", 1/2", and 5/8" SS clevis bolts?
thanks again
dancamp009

 

[Ned L]

Re: are these strange back-stay brackets a weak link?

There are two reasons I can think of for what you have. One is that the backstay was replaced with one that is too short and so an ?extension? was added. The other possibility is that the backstay used to be used as a radio antenna , but this would only be true if the ?pad? between the two halves is an electrical insulator. Also, your boat would have to have been built before about 1972 ? 1974, back when ship-to-shore was AM (it was a common and effective thing to do).
As for a ?weak link? I think I would be more concerned about stress cracking at the 90? bends where the hardware passes through each other.
I would recommend also asking your questions on some sites that are more sail oriented.
--- 45ft wooden mast, - sounds interesting. What do you have? Something wood with nice lines??

 

[dancamp009]

Re: are these strange back-stay brackets a weak link?

Yes, I think you hit it right with the radio antenna possibility. It does have a pad between the two halves that could act as a radio insulator. And she was built before 1972. She is a 1967 Cheoy Lee Offshore 40' sloop rig with very nice lines.
thank you for your help. I think I will remove them and either buy a new back-stay wire or extend the short extender connecting these brackets to the mast head.
much appreciated.

 

[Ned L]

Re: are these strange back-stay brackets a weak link?

Nice boat. Yep, I think I'd do away with that bit of hardware.

 

[dancamp009]

Re: are these strange back-stay brackets a weak link?

You know, on second thought, I do enjoy listening to AM radio, and if you don't think the 5/16" pins are anything to be concerned with, and if the brackets still look to be in fine condition under close inspection, maybe I should keep things the way they are. My VHF radio antenna also sits back there on the deck next to the back-stay, maybe it too is using this back-stay as a reception antenna. Maybe taking those insulation brackets out will interfere with my VHF radio reception. It has no VHF antenna on top of the mast and putting one in now could be difficult running the wire down through the mast, unless I stapled it. . . Humm, lots of maybe's.
thanks again
DanCamp009