Easy setup system for boom gybe preventer.

[jonjo]

While looking at pictures on the Malo yachts web site a few years ago I saw a boom prevented setup that could be retrofitted to my yacht. Does the following sound desirable/sensible?

1. The underside of the boom had a hole large enough to take a reefing pennant size rope. The exit was lined with some sort of fairlead to prevent chafe against the boom extrusion at this exit.
2. The exit was about 2/3 of the way from the gooseneck which on my boat equates to above the sprayhood.
3. The boom preventer line was permamently rigged starting with a toggle and soft eye at this boom exit hole, then the line led back internally through the boom to the coachroof/cockpit clutches following a similar route to other reefing lines.
4. I assume setting up the preventer involved no more than releasing a coachroof clutch, grabbing the toggle and taking the line forward to some strong webbing looped around a fordeck cleat.
5. Then tension the preventer at the coachroom winch/clutch and all is set.

I do not know whether this is a complete description of the system and I have used some guess work. One possible problem is that the section of the preventer inside the boom has a large knot that jams against the boom exit to the securely immobilize the boom. Thinking through the angles and vectors I am not entirely sure a continuous tensioned preventer running from foredeck, to low friction exit hole in the boom, then internally through pulley and blocks at the gooseneck and back to a cooachroof clutch, will fully immobilise the boom. If an internal stopper knot is used in the boom then on my yacht the released preventer line would only reach half way to a forward deck cleat hence rigging becomes more complex.

 

[{151760}]

If you have to go forward to secure. The preventer, I don't really see the advantage of such a complex system. We have a line permanently rigged under the boom, to which is attached with a snap hook, the forward-leading line. This can be rigged in port, if desired. It leads back to wherever is convenient to tension it. The full preventer, when in use, leads from the end of the boom, giving maximum leverage, and is set up from the coach roof. I don't believe any system using rope will immobilise a boom, it can only hold it up within certain limits and/or slow the boom's movement across the boat.

 

[rogerthebodger]

I have a line that has a large snap shackle at each end that runs from the aft end of the boom to a snatch block at the bow. when we are running we attach one snap shackle to the end of the boom run the boom out to the running position and cleat off the other end on the opposite side of the boat.

When we wish to gybe we uncleat the gybe preventer, center boom, change the snap shackle over then complete then gybe, cleating off the gybe preventer again.

If we should ever back the main we can just release the cleated line and control the gybe by letting the bybe preventer out aided by friction on the cleat.

All done from the cockpit

 

[KellysEye]

Our preventer was attached by a U bolt to the U bolt that held the main sheet block and tied to a second cleat behind the main midships cleat.

 

[geem]

i think the ideal preventer set up will vary from boat to boat. On our boat we have slab reefing and we reef at the mast. We wouldn't want any other way on our boat. It wouldn't suit everybody but we have wide side decks, flush decks, granny bars and five winches on the mast so standing securely at the mast is easy.
we had our preventer lines rigged from the end of the boom and taken forward to the bow cleats with blocks that led the lines along the side deck to winches in the cockpit. it worked ok but put lots of line on the side deck that then made going forward dangerous due to the line rolling under you feet. When the lines were tight they were a trip hazard.
We now run the lines from blocks on the toerail to blocks at the bottom of the mast and onto a winch. this works far better for us and since going to the mast is no issue, we much prefer it.
I am sure there are many different solutions for different boat designs

 

[geem]

i think the ideal preventer set up will vary from boat to boat. On our boat we have slab reefing and we reef at the mast. We wouldn't want any other way on our boat. It wouldn't suit everybody but we have wide side decks, flush decks, granny bars and five winches on the mast so standing securely at the mast is easy.
we had our preventer lines rigged from the end of the boom and taken forward to the bow cleats with blocks that led the lines along the side deck to winches in the cockpit. it worked ok but put lots of line on the side deck that then made going forward dangerous due to the line rolling under you feet. When the lines were tight they were a trip hazard.
We now run the lines from blocks on the toerail to blocks at the bottom of the mast and onto a winch. this works far better for us and since going to the mast is no issue, we much prefer it.
I am sure there are many different solutions for different boat designs

 

[sailaboutvic]

Our start at the end of the boom , runs to a pulley block on the bow then comes all the way back to the cockpit , this happens on both side. In this way can gybe and chance the perventer without leaving the cockpit .

 

[PhillM]

I have a block shacked to an eye close to the bow. That happened to be there when I bourght the boat but this could have easily have been shackled to anywhere else forward and on the centre line.

I run a continuous line from the port side cockpit, outside everything, through the block and back to the starboard side. There is a bowline tied in both ends.

On the boom I have a line rigged from the stern end, that sits along the boom and is secured to a cleat. It has a snap shackle on the free end.

When I want the preventer I simply un hook the line on the boom and use the snap shackle to attach it to the appropiate side of the line that runs round the boat. I then secure the other end of the line to the opposite side winch. When it's time to gybe, simply release the preventer, hook up the link to the boom, gybe, re-rig on the opposite side. You can do everything from the cockpit, easily and quickly.

 

[lw395]

Two sorts of preventer:
a) light winds sloppy sea, boom swinging about. Anything goes!
b) big weather running.
For strong winds, we use a line which is permantly spliced to the mainsheet bail on the boom and ties off near the kicker, so it normally lives tidily under the boom.
When needed, either a mooring line to the forward cleat, or the spinnaker foreguy can be used, which has the advantage of being led back to the coachroof so it can be let off easily.