jib shackle

[dawniewilson]

Puzzled...I have a bennetau first 310 with a furling jib. While racing last week the jib came down - the shackle had broken - the pin stripped. Anybody know what would cause so much pressure on that halyard shackle that the beefy stainless shackle would actually strip the pin and bend the shackle?

 

[Jim21895]

There are any number of possibilities:

1.) Undersized pin that did not properly fit in the threads;
2.) Corrosion;
3.) Fatigue;
4.) Low quality metal used in the shackle/pin; and
5.) Undersized shackle.

There may be others as well.

One way to avoid such things is to seize the pin to the shackle. You should also check those things with some regularity.

 

[dawniewilson]

Thanks Jim. Actually a call to Harken supplied the answer- vibration! Harken is sending out a new shackle free of charge and suggests using it with some lock-tight.
Thank you again!
Dawn

 

[Jim21895]

Vibration would cause it to back itself out which is different than stripping the threads. It's very common for threaded items to back themselves out from vibration. Locking them in with seizing wire is the best way to keep the pin in the shackle. That's why some shackles have holes in the head of the pin.

If it backed out, thread locker will help keep it in, but is not a guarantee. Be careful using the red product as that can make it very difficult to open that shackle when you want to later. You might try the blue formula. In any event, you should make inspection of those types of shackles a part of your routine.

If the threads on the pin stripped, then thread locker will not help you.