Tag Archives: Gear

Our quick and easy preventer explained

When I recently wrote about some helpful upgrades that we’ve made to Yahtzee, I included a new preventer setup that I think needs some clarification. Well, I finally had the time to set it up at the dock and take some photos that will help explain it a bit better.

In my mind — and experience sailing downwind — a well devised and rigged preventer is an essential piece of gear aboard. And if it’s done right, it should be easy to set up, release and switch sides after an intentional jibe.

What any good preventer should do is catch the boom in the unfortunate event of an accidental jibe. That being the case, I like to lead the preventer line as far forward as possible. But, and this is the big caveat, every boat’s setup will be different. There is no one size fits all. After safe ease of use, what you want to achieve is a fair lead so the the preventer isn’t chafing.

Here’s Yahtzee’s preventer explained:

When installing a permanent preventer that can be quickly deployed on either side of the boat, the first thing I wanted to achieve was making it so that it could be stowed easily out of the way on the boom. To make this happen on Yahtzee, I measured and cut a length of Dyneema, attached the aft end to the bail at the end of the boom and then ran it about 3/4 of the way forward towards a cleat. At the forward end of the Dyneema I spliced in a stainless ring. This ring can then be attached to a short piece of bungee from the cleat to hold it taut, or to the second portion of the preventer line when it’s fully rigged.

Dyneema runs from the end of the boom forward when not in use.
A short length of bungee cord with a clip on the end can attach to the ring on the Dyneema or hold the coiled preventer that will run forward to the bow while deployed.

When it’s time to rig the full preventer for use, I can simply unhook the coil or Dyneema line and ease the boom out to where I want it while broad reaching or running. The secondary line then runs forward to a low friction ring on a snap shackle that I can move from the bow to the toe rail depending on how and where I want the line to lead.

Boom eased out over the starboard side with the preventer fully rigged.
Preventer running forward to the bow.
At the bow the preventer can get cleated on either side or led through a low friction ring and run aft.

The great thing about this setup is that when it comes time to jibe, Jill or I can un-attach the two lines without having to lean out over the side of the boat. The Dyneema can get quickly stowed on the boom with the bungee and then we can move the other section of the preventer to the new side. Once the jibe has been completed, the ring-end of the Dyneema section gets taken off the boom and re-attach it to the secondary line. When it’s all set, we can tighten the whole thing up and sail on without worry. Simple, quick and efficient.

If you have any questions, please feel free to email me (andrewcross8@gmail.com) or ask in the comments below.