Preventer

[Don Guillette]

This is an important topic and I did not want it getting lost in the accidental gybe topic.Mike (PA) asked why a preventer was not used on the boat I spoke of in the article "accidental gybe". The story behind it could have cost me my life. In my sail bag I carry a some extra gear. One piece of gear is one of the smallest soft vangs that Garhauer makes. I use it as a jib cunningham and as a preventer. It is set up with snap clips on either end so I can attach it to a lot of things.On the race in question, I mentioned to the skipper/boat owner that it would be a good idea to attach a preventer but he did not want to. He felt the wind was very light, which it was, and a preventer wasn't needed. As I found out that was a big judgement mistake on his part and could have been tragic on my part. There is not much you can do to force an owner to do anything. I learned a few great lessons on that day. If I'm on a boat where the owner is not practicing what I know to be good seamanship I am extra vigilent. Also, the next time he calls me to go sailing with him I explain what I expect. If he agrees, I go. If not, I pass. Additionally, I never leave the dock without my self inflator on.

 

[tweitz]

I find little information in the usual sources how to rig a preventer, as opposed to why I shoul have one. On my Beneteau 323 I was thinking I would rig a preventer from near the back of the boom, then to a snatch block near or at the stem, with the line coming back to some solid fitting or cleat on the back of the coach roof. I have seen people refer to including a "weak line" in the preventer. I was thinking of using nylon line for some shock absorbing characteristic. What is the purpose of the weak link, is it really necessary, and is there aything wrong with my plan for the preventer?

 

[tweitz]

correction

That should read "weak link," not "weak line" -- although I guess a weak line would be a weak link.

 

[RichH]

So that you dont break the boom if it 'goes under'

If the boat rolls severely to the side so that the boom/main sail 'scoops' water ... the usual result is a broken boom and perhaps a split mainsail. If the preventer has a 'fuse' or weak link, you hope that the 'fuse' breaks and frees the whole system before the boom and mainsail either bends/breaks/splits.

 

[Ross]

I have said in other places that you trim

the main and then take the slack out of the preventer. The preventer need not be as strong as the main sheet. Neither will it eliminate the dangers of stupidity. It will help to keep the main on one side of the boat during lulls in the wind and MINOR lapses by the helm. Nylon will stretch like crazy if you get the full force of the wind on the back of the sail.

 

[tweitz]

Perhaps I am excessively dull, but if the link is weak, and you let the wind get on the wrong side of the sail, won't it jibe anyway and not prevent anything?

 

[Don Guillette]

What not to use

I seen a lot of different preventers and the one that scares me the most is BUNGEE CORDS. I've never seen one let go but I know some guys who have. In one case the metal end let go under strain and had it hit someone it would have caused serious injury. Do not use bungee cord for a preventer.What I like about my setup (what I like is not what everyone likes) which is a small soft vang is that it is strong enough plus easy to adjust and release quickly. If you find yourself having to release whatever preventer devious your using quickly your not paying attention to your sailing. You should be thinking ahead of the preventer not having it do your thinking. In 95% of the situations the preventer should not even come into play if your paying attention to what you are doing. The main use of the preventer is to tip you off, in most cases (unless there was a severe wind shift), to a mental lapse. In other words, like oopps I almost lost it and then quickly make the steering adjustment.

 

[NautiDuck]

Just to make sure

I do not have a reventer but am thinking I should on my Catalina 22. Am I understanding correctly that, when sailing downwind, the preventer should be in use and that the preventer should be reset on every jibe?

 

[Ross]

You can not purposely jibe while a preventer

is in place. So it must be released for each jibe. If you plan to do a lot of down wind sailing then rig port and starboard and treat them as you do the sheets, one is always working and the other is lazy.

 

[Don Guillette]

Every Gybe

Randy K: On a C22 you might be able to get away without a preventer but chances are you will be moving up eventually to larger boats (I started with a MacGregor22, then to a C25 and finally to a C30 - I was looking at a C34 before we decided to move to Tucson!!) or chartering and you may as well establish good sail trim habits now. You also might crew on larger boats and you don't want to be in the same situation I presented at the start of this thread where the boom could possably take your head off. In other words, if the skipper does not want to rig a preventer you will be extra diligent for the accidental gybe.On each gybe you would reset the preventer because the boom would be on the other side of the boat but even if you stayed on the same downwind course but decided to head off a bit you would want to reset the preventer. Lets assume on your new heading there was some slack. Personally I don't like the boom bouncing all over the place so I always take up the slack. I hate to keep bringing up the soft vang as a preventer but in the cases where an adjustment is necessary you can visualize how easy it is for me to make it with the soft vang as opposed to working with a line I have to tie off each time.Randy, where do you sail your C22 in Eugene? I assume you trailer to the coast.

 

[Mike]

My preventer

There are two Catalin 22s in the family. What we did was place a heavy duty snap hook, (similar to those that some people use for their bow line when tied to the slip), on the bottom of the boom vang. It is very quick and easy to detach the bottom of the vang and re-attach the vang to another point. The vang line is long enough to allow us to make the switch.When sailing downwind on Pymatuning lake, it's not unusual to get a shift in the wind, because the lake is long and in some places narrow. The wind bounces of the tree line of the shore. When on a long downwind run, even if not dead down wind, once the main sail is eased out, the vang is relaxed, unclipped from the mast base and reclipped to a point forward of the mast. On my boat, I installed an eyebolt, with good backing to each side of the deck. Our other boat has stanchion bases that are designed to attach the vang. One thing I noticed in these threads is that some people claim that the lifeline stanchions are not attached very strongly, and could pull loose from the deck. Our stanchions are backed by very heavy backing plates, and through bolted with lock washers and nuts. I suggest that anyone who has lifeline stanchions on their boat that aren't through bolted, should do so immediately! Some boats have a toerail and they could use that as a place to attach their vang to create a preventer.I also never leave slack in the vang after it's been switched to be my preventer. It's the shock load that exerts the most force, and if you 'prevent' a shock load with a preventer, your boat is less likely to suffer damage. Another thing I do is put a safety knot in my main sheet that keeps the boom from ever playing out to a point where the boom could ever, ever, ever make contact with a shroud. I have an aversion to being dismasted if there ever would be an accidental jibe.

 

[Rick Macdonald]

vang/preventer

The link below is to a fascinating article about about what they call a "vang/preventer". They replaced their boom vang with two soft vangs, hooked them up to the port and starboard toerails and then both to the boom, and ran a continuous line through the two of them!Not quite for my boat, but it's a cool idea that is a combination of all the ideas we've been tossing around. They're always in use, don't get in the way, have mechanical advantage, etc....RickM...

 

[NautiDuck]

Don and Mike

Don, I sail on Fern Ridge Lake. It is an Army Corps of Engineers lake used for flood control. It is full March through October. Great sailing lake. We have had the nationals of various fleets, two years ago the Santana 20 Nationals.Mike, I like the idea of using the boom vang. I already have quick release clips on it to facilitate raising the poptop.Don, I too wear a self-inflating PFD every time I step on a sailboat. As for moving to a bigger boat, well I happen to be working on the Admiral now for a Catalina 250!

 

[Don Guillette]

Best words ever uttered

Randy K: Here's how my boat purchasing went. We bought a Macgregor22 at lake Havasu, AZ because I was sick of my sons bringing my 22' Jet boat with a 450 Ford with two 4 barell carbs etc back to me in pieces!! After we bought the sailboat my sons never asked to use it - it was too slow for them. The problem with Lake Havasu, AZ is it blows either 90 knots or zero knots so in order to get more use out of it I towed it home to use in Long Beach, Ca. My wife would not go on the boat if I wanted to take it beyond the breakwater and then one day she uttered those magic words - "MAYBE WE SHOULD CONSIDER A LARGER BOAT!!" BAM,BAM I was on that the next day!!. The only problem was I wanted a C30 but our jobs were shaky so I bought a C25, which I felt I could get out of the water easily if the job situation turned bad.The job situation did turn bad but we managed. When everything stabilized we enjoyed the boat but one day I heard those MAGIC WORDS again regarding a C30 and BAM, BAM, BAM I was on it again and after a search of about 25 C30's from Ventura to San Diego I finally found the C30 I was looking for in Newport Beach, Ca - 25HP diesel, teak and holly floor etc.Keep the faith mate and keep looking and playing for (most woman are easy to work - I hope a lot of gals are not reading this) those magic words!!

 

[NautiDuck]

Got the OK

Don, Admiral has OK'd the purchase of a larger boat. Now seeking a Catalina 250 Wing Keel in good condition. I feel like a kid again!!

 

[Ray]

Teaching preventer use to new sailors.

I have been teaching new sailors to mount, rig and use preventers for the last 3 years. In our area 90% of the boats are 27 feet or less in length and therefore easly rigged for this devise. My thought is that if I make this the same as seatbelt use in autos then these students will carry this practice upwards as they graduate into larger boats.I set this up on each side of the boat and it requires less that a minute to use. It surely eliminates a few Excedrin headaches each season.I also teach each student how to "heave-to" on his/her own boat in the early part of their training. This allows them a "zone of calmness" while the environment around the boat is "going to Hell". They now can rethink what needs to be done and change their sailplan as needed.We sail on the upper Columbia River and the smaller boats used call for some different approaches than larger boats in saltwater.Preventers simply remove, what I consider, the largest danger out to get new sailors.RayS/V Krusty Krab

 

[Don Guillette]

Teaching

Ray (Kettle Falls, WA): Please send me your Email address at yankee3223@juno.com. I have a general teaching technique question that I think you can help me with.

 

[Rick Macdonald]

Ray - both sides now

Ray - just curious, do you rig preventers such that both sides can be connected at once and the boom still has full range of movement for gybing/tacking, or are they too short for that?When I set mine up, I had lines long enough for the boom only to return to the centerline. On a (much larger) chartered boat, I rigged preventers from what I think may have been spinaker lines. They were long enough to attach both sides and leave them connected. I liked that better.My preventers are single lines with no mechanical advantage. Mine turn through blocks and terminate at horn cleats at the stern....RickM...

 

[Ray]

Rick, Two seperate lines from set from cockpit.

I sail a 1980 C22 but the set-up is the same for all the boats we have rigged. The largest so far has been a 27 foot.I mounted a SS eye strap on each side or the cabin top at the outer edge outboard of the mast and mounted a pair of Ronstan series 40 blocks. This eye strap has a backing plate on the inside of the cabin where the nuts are secured. I then mounted a set of C-cleat line locks on the cabin side at the front of the cockpit. About 2/3 back on the bottom of the boom I rivitted another eye strap. I run a line from the c-cleat forward to the block and then it runs out and back to the eye strap on the boom. The line has a carabiner on the boom end. I simply clip the line to the boom and swing it out and cleat it off. I rest both lines in the c-cleat when not in use. You can make the lines long enough to leave both hooked up but that gets a little busy. It's so easy to grab the carabiner and snap it on and then swinging the boom out that I do it that way.It makes it much safer for newbies (and older complacient sailors) and by requiring its use and the use of life jackets I know I won't be bringing home any broken or waterlogged heads.RayPS. Don, I'll e-mail in the morning. I also am regestered on this site under Ray Bowles.