Halyard Hook Failure

Hi everyone,

I had the halyard hook on my Hobie 17 fail. The mast has a composite comp tip where the halyard hook is mounted using rivets. It had been dropped by the previous owner, creating a small crack in the hook that propagated over time. I purchased a new halyard hook assembly (50403011). I am unsure how to approach the removal of the rivets and the best practices to ensure a long lasting repair. I intend to drill the rivets out. Is there any where I can find more information about this type of rivet? Will I be able to reuse the same rivet holes in the mast?

Drilling out old rivets. Use hobie rivet casings over new rivets to seal new rivet holes and reduce possible slop from drill out. Good luck.

The rivets pass through the fiberglass comptip and into the aluminum mast head cap. They are 3/16” diameter stainless steel. I’m not sure of the specified length, but 1/2” should work.

When removing the old rivets, use an over-sized drill - 5/16” or 3/8” diameter to drill off the rivet heads only. If the rivets spin when drilling out, you can use a dremel tool or angle grinder to remove the heads. Once the heads are off, use a 3/16” straight punch and hammer to drive the remaining rivet shank into the mast. This is the best way to prevent over-sizing the holes in the mast.

I recommend leaving the rivet shanks inside the mast, rather than trying to take off the head cap to get them out. The head cap is a snug fit to the mast and is probably also attached with sealant. Removing the head cap would likely require tapping out with a hammer, which risks cracking the fiberglass comptip (I am speaking from experience…).

Installing the new hook and rivets is straight forward, but you will need a heavy duty rivet gun to pull the stainless rivets. Also, make sure you put all six rivets in the holes to get everything lined up before you start pulling any rivets.

sm