Rigging preventer lines H260
- Thread starter Chuck C.
- Start date
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,297
Chuck. Perhaps it is important to understand the reason and conditions you want to use a preventer.
Preventers used in cruising where use maybe for extended periods, in conditions that the boom might dip into a wave, or sudden squalls and strong winds my suddenly appear have far different force issues than the day sail experience in moderate conditions.
Experience 1 needs to recognize the extreme force conditions and design the preventer to mange them without breaking the boom while being adjustable.
Experience 2 can use lighter tackle and may take advantage of lighter force conditions when designing attachment points.
What sailing conditions do you anticipate in your sailing adventure?
Preventers used in cruising where use maybe for extended periods, in conditions that the boom might dip into a wave, or sudden squalls and strong winds my suddenly appear have far different force issues than the day sail experience in moderate conditions.
Experience 1 needs to recognize the extreme force conditions and design the preventer to mange them without breaking the boom while being adjustable.
Experience 2 can use lighter tackle and may take advantage of lighter force conditions when designing attachment points.
What sailing conditions do you anticipate in your sailing adventure?
Use stretchy nylon line with snap hooks on each end that allow you to quickly disengage or switch sides. You can anchor the forward end to a stanchion base, the boom end to a loop of line that can be left in place. You want the preventer line to be somewhat stretchy to reduce the shock on the deck and boom fittings.
The articles (with diagram and photo) below explains how to set up a preventer.
www.sailmagazine.com
sailingmagazine.net
Below is a diagram of how it was set up on a Hunter 260 from Mistress of Grand Traverse
Boom Time
"Yachts shall comply with the US SAILING recommendations of OSR 5.11, Preventer or Boom Restraining Device. The boom-restraining device shall be installed and demonstrated at the time of the yacht's mandatory courtesy inspection. A process and plan for its use shall be part of the crew's...
www.sailmagazine.com
How to rig a preventer
A boom violently crashing across a cockpit can be deadly, toss a crewmember overboard or cause serious damage, so it’s worth making an effort to prevent it from happening whenever possible.&nbs,Technique
sailingmagazine.net
Below is a diagram of how it was set up on a Hunter 260 from Mistress of Grand Traverse
On my H23.5, I rigged my preventers exactly as shown in Georgia's handy-dandy diagram. Except, I run the lines through the blocks on the shroud U-bolt blocks back to the stern cleats instead of a stanchion base. I attach the snap shackles to the same eye as the mainsheet. I'm never in really big winds on my small Lake. When going dead downwind I use the Preventer on one side and a whisker Pole for the jib on the other and it's rock solid.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,297
Preventers for "light weight work" can find the stanchion or the shroud a serviceable anchor point as excellently explained by @sail sfbay.
Before I examined the amount of force that is associated with a strong wind backing a sail that is dipping the boom into wave top I was happy to attach my preventer to a ubolt in the deck mid beam near the shroud. The sudden forces experienced by a preventer in a strong breeze gybe can break a boom, break a stanchion loose or destroy a preventer while the boom swings wildly across the deck.
Sailing in big water with tacks that run for hours on a cruise, I now attach the preventer to the end of the boom with a strong Soft shackle (10K break strength - cost - a little skill and less than $3.00 of materials). I run the nylon double braid outside all rigging to a strong cleat near the bow, thru a sizable block attached to the cleat with a strong soft shackle. The preventer is then run back to the cockpit on the side that the boom is flying to a cleat or the Self Tailing winch. I set the sail by letting the mainsheet out to where I want the boom then pulling on the preventer to line to tighten and fix the boom location against the mainsheet.
This sets the boom in a fixed location that not a dip in the wave or a sudden wind change can affect the boom till it is trimmed differently. With the long preventer line there is plenty of stretch to allow the preventer line to absorb any shock due to wind or water.
Before I examined the amount of force that is associated with a strong wind backing a sail that is dipping the boom into wave top I was happy to attach my preventer to a ubolt in the deck mid beam near the shroud. The sudden forces experienced by a preventer in a strong breeze gybe can break a boom, break a stanchion loose or destroy a preventer while the boom swings wildly across the deck.
Sailing in big water with tacks that run for hours on a cruise, I now attach the preventer to the end of the boom with a strong Soft shackle (10K break strength - cost - a little skill and less than $3.00 of materials). I run the nylon double braid outside all rigging to a strong cleat near the bow, thru a sizable block attached to the cleat with a strong soft shackle. The preventer is then run back to the cockpit on the side that the boom is flying to a cleat or the Self Tailing winch. I set the sail by letting the mainsheet out to where I want the boom then pulling on the preventer to line to tighten and fix the boom location against the mainsheet.
This sets the boom in a fixed location that not a dip in the wave or a sudden wind change can affect the boom till it is trimmed differently. With the long preventer line there is plenty of stretch to allow the preventer line to absorb any shock due to wind or water.
Two different systems depending on sea state and windforce, makes sense. My H260 is a lake sailer in mostly light air and I want to prevent (another!) accidental gybes while on a run. With the snap shackle to the mainsheet bale and a snap-on block at the shroud U-bolt, its quick and easy to rig just when you need it and you only need one set Good stuff, thanks!
Chuck
Chuck
One line meaning you can simply unhook the block and move it and the line over to the other side if you switch tacks. Once the boom is out in position, you have to tighten (adjust) the preventer line, pulling the boom forward with it while the mainsheet is hard. Its probably easier to set up two lines, but on a run I generally don't gybe that often.