Preventer / Vang & COMPLETE MAST RENOVATION

[waterdog]

My rigger suggests a snap shackle on the lower end of the tackle on the Garhauer vang so it can be disconnected and run forward to an attachment point at the shrouds to be used as a preventer.   I like the concept.  Does anybody do it this way? 

[Stu Jackson]

Sounds like the soft vang, not the rigid one, because the rigid vang connection to the boom would preclude that.

You need BOTH the vang and a preventer when sailing downwind.  Depending on the angles, the preventer could pull down, too.

What we do is use the cunningham as a preventer with a snap shackle on its connection at base of the mast to one of the shroud bases below the turnbuckle,  and move the cunningham tack hook to one of the mainsheet bails.  We then balance the rigid vang and the "new" preventer for proper boom position.

[Jon Schneider]

What we do is use the cunningham as a preventer with a snap shackle on its connection at base of the mast to one of the shroud bases below the turnbuckle,  and move the cunningham tack hook to one of the mainsheet bails.  We then balance the rigid vang and the "new" preventer for proper boom position.

That is BRILLIANT!  Of course... you don't need the cunningham when you're running downwind; may as well put it to good use.  Yay, I cancel my pad eye project this year that I was going to install for the preventer.  Now what am I going to do with all that time saved?  Oh, yeah, maybe go for a sail. 

Speaking of -and of no relevance whatsoever to all you year-round sailors- my boat splashed last Thursday.  It was last out and now first in in the marina.  I bent on the genny, but there was not a breath of wind this weekend.  An inauspicious beginning to the new season. 

[Roc]

I find connecting a preventer to the shroud base, or worst a stanchion, is not a good idea.  Those points are not really meant for such a strain in the event of an accidental jibe.  Wouldn't the best place be at a midship cleat (if there is the opportunity to have one there)

[waterdog]

I find connecting a preventer to the shroud base, or worst a stanchion, is not a good idea.  Those points are not really meant for such a strain in the event of an accidental jibe.  Wouldn't the best place be at a midship cleat (if there is the opportunity to have one there)

What would be a stronger attachment point than the chainplate at the base of the shroud?

[Jon Schneider]

What would be a stronger attachment point than the chainplate at the base of the shroud?

There's no doubt that that would be a strong attachment point, but I wouldn't want to do it, because it would adding a lateral force to the chainplate when it wasn't intended as such.  I'd leave them alone and let them serve their single purpose.  If you need an alternative to Stu's suggestion, I would go with thru-bolted, back-plated pad eyes on the deck. 

[waterdog]

My boat is cunninghamless.   I have a lived 2 years of happiness without a cunningham (hell, I even lived one year without a vang.)   Why do I need a cunningham?   In what circumstances do you use it?    Are you a happier man with a cunningham than without one?

The following is Stu's answer to Waterdog's original question quoted above: 

"My main halyard is StaSet, a dumb move on my part when I replaced it when I redid the standing rigging a few years ago.  Combine the stretch of that halyard with a 22 year old mainsail and scallops develop on the luff as the wind increases with the main fully up (I get great performance when reefed  !).  Rather than re-jack the halyard, we installed the cunningham.  It took the place of the jib halyard run back to the cockpit, because the jib halyard's always up, so I added another cleat to the port side of the mast for it (and the backup jib halyard on the existing cleat).  We can tighten the cunningham and get rid of the scallops anytime.  We ease when going downwind.

I'm also not a great fan of snap shackles.  Once one of those puppies let go on me when I was up the mast on a bosun's chair!  It was on our old C25, so I got down in a hurry by myself.  I'd use them and do for a preventer, but would not recommend them for the rigid vang "soft" connection replacement.  And, as noted, we use both the vang and the cunningham cum preventer together when using the preventer.  The mainsheet out as far as possible on the traveler also has some vertical component, but not much by the time the sail is way out.

For Roc, of course no one should use a stanchion!  I get mad at anyone who touches one.    The shroud base has what are essentially double jaw toggles, so the angle of pull is meaningless and the structure and chainplate connections down below are designed for tension anyway, so shroud bases are a perfect place for preventer connection points.  The midships cleat on our boat is on the jib fairlead track.  I recall it being too far aft to be of much use, and not big enough to handle a snap shackle through the foot of the cleat.  We do NOT have an outside track, which Kyle mentions in his later post - good idea there. I wouldn't recommend its use on a Mark II with the outboard midships cleats, they aren't made for that kind of load."

[Jon Schneider]

Now my ignorant question.   My boat is cunninghamless.   I have a lived 2 years of happiness without a cunningham (hell, I even lived one year without a vang.)   Why do I need a cunningham?   In what circumstances do you use it?    Are you a happier man with a cunningham than without one?

Sorry to hog your question to Stu, but yes, you will be a happier sailor (not sure about the man part) with a cunningham.  You absolutely need a cunningham to control lower draft in the main.  You really can't do it without one, and if you rely upon the halyard, you won't get as a effective control in the low draft, and you'll be stretching the hell out of the luff bolt rope.  Come to think of it, when I tune my main using the cunningham, I am a happier man. 

[Gary Brockman]

When I bought my boat last year one of the recommendations in the survey was to replace the upper shroud toggles as the PO had used them as a base to connect a soft vang as a preventer (boat has a solid vang). The practice of connecting the preventer to the toggles had distorted the upper toggles on each side and there was a question about their integrity.

Just a thouhgt.

- Gary -

[Kyle Ewing]

My preventer runs from one of the main sheet points on the boom through a block on my outside genoa track then back to the cockpit where I tie it off on a cleat.  I can adjust tension as needed so an accidental gybe doesn't put a large shock load on the system and quickly release it if I have to.  I can also safely slow the boom during a planned gybe easier than using the mainsheet.  After a gybe I move the preventer line to a block on the opposite track.

[waterdog]

Stu?   Did you assume my identity?    I think maybe you were wearing your moderator cape in typing a reply.   On my computer at least, it looks like your words posted under the waterdog banner.   Does this mean I'm Stu?   Muwahaha.   I'm going to provide links to people.   All the wrong links.  I will become Dark Stu, Lord of the Bilge...

[waterdog]

You absolutely need a cunningham to control lower draft in the main.  You really can't do it without one, and if you rely upon the halyard, you won't get as a effective control in the low draft, and you'll be stretching the hell out of the luff bolt rope.  Come to think of it, when I tune my main using the cunningham, I am a happier man. 

And here I thought I was just a man with a baggy old main and you tell me a cunningham will get rid of the bag.  I really need to start racing.   There is nothing for sail trim quite like racing.   When I'm cruising and I don't like the sail trim, I just go below and get a beer and usually there is a wind shift or a fish on or something and I forget about sail trim without ever looking critically at my bag and saying "damn I need a cunningham".   

[Jon Schneider]

Oh Lord of the Bilge, a point of clarification: the cunningham won't so much make your old baggy sails new again as it will shift the draft aft (upon tensioning).  In doing so, that may also decrease the size of your draft somewhat as well, but if your sails are blown out, they will remain blown out.  Another sewing project.

[Stephen Butler]

We have a stick-redo project on the to-do list.  Yours looks great!  Some questions: how difficult was it to remove the fittings from the mast?  What tool(s) were used?   Did you have to re-tap the bolt holes in the mast?  We have been told that removal of the fittings is the most challenging part of the project....you experience please.

[waterdog]

My mast went back in the boat today.  Stunningly beautiful.  Better than new and I know every fitting and wire in it.   Here is the skinny on the fittings.

I never started out on a mast redo project.  The rigger looked at my mast and said "there are almost no fittings on it, you should strip in down and we should paint it."  He let me use his shop and tools and my labour.   I'll go top to bottom for an '88 keel stepped mast.

On the masthead.   Numerous bits of stainless screws - spinnaker crane, anchor light, windex, wind instruments etc.   These were pretty much all nasty to remove - I used a torch, I used vise grips, grinders, drills. everything.   The good news is the whole box is held on by one through bolt which was easy to remove.  So you can take the masthead box home and put in your vice (gently).   Pins for the halyard sheaves pull out by removing two cotter pins - really easy to disassemble.   Messing about, pressing out old bushings and pressing in new ones on sheaves was a very easy job. 

Next down the mast are the fittings for your upper shrouds.   Hereafter, I'll probably get names wrong, but others will correct as necessary.   This one is a through bolt (easy to take the nut off with a couple of big wrenches.   There are two cover plates with four rivets each.   The rivets need to be drilled out.   In theory it all comes apart nicely.  I had one of these (there is one for your uppers and one for your lowers) come apart easily.   The other they had put an aluminum compression sleeve in one side and bolt in from the other side and the two dissimilar metals had fused together.    There was no way to remove it.   I hammered.  I heated.   I couldn't get it to budge.   Messed around for an hour trying to preserve my precious hardware.   Finally they came along with a zipcut, lobbed the head off the bolt and put me out of my misery.   It was a five dollar bolt, not something worth wasting hours of my life on.   I cut new compression sleeves out of stainless tube to the correct length.   The factory put in aluminum compression tubes a half inch too short - useless.   The compression tubes stop the mast from compressing under the load from the bolt / pull from the rigging.  Thankfully, we have sturdy masts and having short compression tubes didn't matter. 

Working down the mast, you'll come to an upper exit for a spinnaker halyard.   It's held on by four rivets.   These drill out.  Your first of five halyard exits will take a couple of minutes to remove.  The rest will go more quickly.

Soon you come to the spreaders.   These were held on by four overly long clevis pins.   Pull cotter pins, tap the pins out, no problem.   I have to say the bottom of my spreaders were covered corrossion embedded with green slime (such is life in the Pacific Northwest).   For me having beatiful spreaders was worth the whole project.   

Below the spreaders are the lower shrouds.   Same through bolt, tang, cover plate, mast, compression tube, mast, cover plate, tangs, nut combination as the uppers.   

Gooseneck came off easy.   8 big screws.  Maybe a little heat required.   A large screwdriver with a square shaft and wrench applied with plenty of weight works wonders.   

Vang came off easily.   This was installed by a genius who used hex cap screws and plenty of lanacote    

Mast boot was cutting, scraping, brushing, sanding.   

There were the odd eye strap and cleat.  No problem with these.   Rivets to drill.  Screws that unscrewed.   

The boom was a much bigger issue.   I destroyed cleats.   I had to drill the ends off.   The last screw in the track I could only get out by rotating the whole track.   

I have to say removing all the hardware was not nearly as big of a challenge as I thought.   But it was really good to have experts to call on and ask how to do things.   

Sanding was a big job.   I started with 80 grit.   Every point where there was electrolysis, went down to bare metal.  Every edge where there was a chip was feathered back.  You have to sand it working your way around the mast back and forth.   Not up and down in long stripes or that's what you'll get after its painted.   

Total time into it was about a week and half of my time (mind you I show up at 10 after dropping Foster at school and many days left at 2 to pick him up).   So full time maybe a week.  If I paid the rigger to strip, sand, polish the bits, run to fastener supplier,  etc. it would have added about $3000 to the rigging bill.   

As it stands, I have no idea what my rigging bill is.   The rigging itself was $2300 cdn plus turnbuckles, plus the crane, labour to step and unstep, insulators for the backstay, a bushell of garhauer blocks, 460 feet of new halyards, 72 rivets, paint (not cheap), painting labour, fasteners, mast crane fabrication, tricolor/anchor light, several hundred feet of various wires.   I wrote a cheque for $3000 and will square up next week some time. 

I wouldn't hesistate to do business with same shop again.   Anybody who will give you two dollar bushings to press in instead of selling you expensive new sheaves is somebody you enjoy doing business with. 

If I ever sell Blackdragon, I'm going to list it as a 2009 model with a retro transom...