Ever had a shackle bend ?

[andrewhopkins]

Out sailing in a F3 on Saturday when suddenly the head sail drops 2 feet. I look up and see the halyard has come undone so I put the engine on and went into the hamble.

My friend hoisted me up to fetch the halyard down with the furling unit and on inspection, the shackle no longer closes.

It seems that somehow the whole thing has bent out of shape so the arm swings round but misses the spring loaded pin.

£42 later and i'm back and running but these things are meant to take 8000lbs according to the new one!

Is this normal ?

 

[Trevor_swfyc]

Andrew,

This will teach you not to take URI GELLER out for a sail!

All the best
Trevor

 

[yoda]

Snap shackles may take 8000 lb in a straight pul but start to put a twist on them and things you don't want to hapen do! If this is just the furling headsail halyard shackle that normally stays attached why not use a plain shackle and save a few bob?

Yoda

 

[Twister_Ken]

No, but I have had lots of sheet bends. nm

§

 

[vyv_cox]

Have you applied load to it when it had come undone? Bending of the arm out of alignment is difficult to imagine if it was closed, even at more than 8000 lbs.

 

[andrewhopkins]

Nothing special

It was under its usual tension and quite happily held on Friday in a F2 but on Saturday in a F3 it just went. The shackle had been close properly but when we brought it down and examined it it was really bent.

I cant believe you could do this with a winch anyway!

The eye and the pin were almost 10mm out of alignment

 

[graham]

Re: Nothing special

I strongly suspect that the damage was done AFTER the shackle undid itself.

As a precaution to stop it reoccuring can you seize the pin in possibly using cable ties to prevent any vibration shaking it out?

 

[ponapay]

I had a similar strength shackle (SS) break, it sheared across the bow at the top of the unthreaded lug.

Inspection with microscope found typical fatigue failure marks and crystalisation of the metal. It would appear that the shackle had probably developed a small crack which had then concentrated the stress in a small part of the shackle.

The result was impressive, we were broad reaching in a force seven and the shackle connected the mizzen boom to the top sheet block, the mizzen skyed and then tried to gybe. There was an almighty bang when the shackle went which frightened the crew (and startled the skipper).

It was my fault, I should have checked the shackle more closely at the start of the season.

Ian
ponapay@aol.com

 

[Plum]

I assume you are refering to the usual U-shape screw-pin type stainless steel shackle. Did you have seizing wire on the pin? I have had bent shackles, but if they do not come undone I do not see how they can be bent by the ammount you say.