Windlass replacement bolts?

[jep27]

Last fall, while replacing a friends sailboat buy in 4-5 foot waves, our anchor mount got caught and ripped off. All four bolts sheared flush with the deck.

My question is: are these bolts designed to shear under a certain amount of torque? Or.. just standard stainless bolts?

I’m certainly glad that the bolts did snap… before more damage was done to the fiberglass hull/bow.

Thanks for any inputs…

 

[thataway]

Last fall, while replacing a friends sailboat buy in 4-5 foot waves, our anchor mount got caught and ripped off. All four bolts sheared flush with the deck.

I believe I need an interrupter here. What caused the 4 bolts on the Windlass to shear? Were you being towed by a sailboat in 4 to 5 foot seas? If so the entire vessel should have been bridled. Never trust deck hardware when using a tow line, except if the tow bit is designed for the load of several thousands of pull.

The SS bolts for the windlass I believe are metric and metric thread. They are not designed to take much more Thant 1000 lbs load--and one should never ride with the anchor chain or rode fixed to the windless instead of a proper bridle for the anchor (different than bridling the boat.

However they are not designed to shear at a certain load pressure. Was there any crevice crack corrosion around the base of the windlass on these bolts? I would expect that if the bolts failed.

 

[ssobol]

Stainless is not all that strong. You should use grade 5 or 8 bolts. Grade 8 is stronger, but also more brittle.

 

[jkidd]

Just call the vendor and have them send you 4 more bolts. Or ask them the specifications so you can get them locally. Using grade 5 or 8 would be steel bolts and that would be dissimilar metals and they will rust and corrode. You don't need to make them any stronger than what the factory supplied. Just don't repeat what you did to shear them off.