the Vang bang

[tonyquoll]

G'day

It's blowing a gusty 18-25 knots, so I've got everything pulled tight to flatten the sail; downhaul, outhaul, vang, lower forestays.

I try to haul the vang on enough that the mast doesn't rotate past 45 degrees; as that might cause it to get a permanent side-ways bend.

Because I run the boom fairly low and the boom attachment point is a bit far forwards, when the vang is on hard the blocks touch.

I'm going upwind with the traveller about 200mm from center, working the mainsheet a lot; hauling in to get speed up and dumping it when huge gusts blow the boat over and almost lift it out of the water.

Bang! The 1/4 inch stainless bolt that holds the vang lever to the mast step shears through, releasing a bit of vang tension & one side of the vang lever.

I guess it's because I eased the main that the tendency for the sail to twist and the boom to lift was all being held by the vang.

So what's wrong here? Just a dud bolt, a problem with the hardware or problem with they way I was using it?

Any feedback welcome,

cheers

tonyquoll@yahoo.com

[h20melon]

The bolt should be replaced every 3-5 years or so, as with some other bolts and rivots on the boat as they are under a lot of load.

Chainplate turnbuckles according to Ronstan should be replaced every 3 years.

[tom]

That is a fairly common problem.

Mostly i think it's caused by having the wrong bolt, you need to make sure that both sides of the vang are sitting on the full shank of the bolt, and not over the threaded portion. Mostly this means you will be buying a long bolt and cutting off most of the thread and using a washer to ensure the loaded part of the vang can't rest on the thread.

[tonyquoll]

Thanks for the great insight & advice;

the bolt did shear through a threaded part.