Blue Water Essentials in a Small Cruiser
Passage Preparations for the Vivacity 20 Part lll
The Standing Rigging
by Dave Chamberlain
All rights reserved
Back in 1986 on a crisp spring Saturday afternoon on San Diego Bay, I was racing my quarter ton racer (a completely reworked and raced-out Venture 21. “Havilah” had just rounded the downwind mark and was clawing toward the weather mark with a single reef in the mainsail and a 120 genoa. She balanced perfectly in the fresh breeze and she was leading the race. I was on starboard tack concentrating on the genny’s tell-tales trying to keep her in the groove when abruptly…Bang! Slam!
There was a horrific onboard explosion. My mind raced. Could I smell black powder from a cannon fired nearby? Was San Diego under siege? No, the lower shroud turnbuckle had violently and suddenly given way. The mast groaned and bent over 50 degrees and was barely held by the starboard upper shroud. The mast step was badly bent and the mast itself bowed in unrepairable condition.
Preservation of the propulsion system is of utmost concern for every sailor. The standing rigging is often the most overlooked component of the cruising equation. The condition of the rigging must fill the skipper with confidence. There can be no question as to its integrity. The small craft must be able to survive the gale with storm sails or bare poles, putting up with the violent whipping action generated by large waves, then regroup and sail on to the destination.
The small boat solo sailors of the turn of the century had a strategy of lowering and lashing their masts on the deck of their small craft during gales. This was especially true with the small yawl rigged cruising canoes. I don’t know about you, but I can barely take down and set up my mast in protected water let alone getting the deed done while traipsing around 10-foot wind waves.
When cruising, my twenty-foot Vivacity carries ten stays. Everything is doubled up. The headstay is attached to a beautifully cast bronze deck fitting. I wanted to see the tension stress the hull as well as the deck. The tension of the headstay must get to the hull somehow. To achieve this I took off the bronze fitting and applied many layers (8-10) of 6 oz. Fiberglass cloth under where the fitting is attached to the deck glassing the deck to the hull and made it as strong as I could then redrilled the holes for the fitting and set it all in 3M 501 sealant and bolted the bronze stem fitting home. I also drilled a new hole right under the roller so the headstay could not lever it’s self up and out. I believe this has made the deck fitting much stronger. Also, I set a storm jib on a stay just aft of the Sampson post which is attached to a bridle up by the spreaders on the mast. Two forestays are better than one. My staysail is not used in light and coastal sailing.
The Vivacity comes with twin backstays which also serve as a second upper shroud. For those of you that have twin backstays..check out the tension on the windward backstay while sailing on a beam reach and you will be amazed at how much help the backstay is providing in lateral support. In my opinion, all off-shore vessels should have twin-backstays.
The Vivacity comes stock with U-bolts attached to the special reinforced area of the deck next to the toe rail serving as attachments for the shrouds and turnbuckles. Once again, the thought of an overstressed shroud pulling up the deck drove me to, at least a perceived, need for true chainplates that spread the stress of the shroud tension down to the hull. I cut my chainplates out of 1/4” stainless stock plate (that used to be a drop-keel for an Islander 23). I used an abrasion wheel in a Skill saw and shaping the radius with and a grinder. For and limited skill kind of guy, they turn out fine. I used backing plates which were glassed to the inside of the hull to further spread out the pressure. I made eight chainplates. Four for the lower shrouds, two for the upper shrouds and two for the twin backstays. I used 3/8s bolts and self-locking nuts. Two important items: 1) Be very careful cutting out a slot in the beautiful 1/2 round hardwood sheer for the chainplate. 2) Only drill through the hull for the lowest chainplate hole. You should have at least 3 holes. Don’t drill the upper two holes until you have the mast up and the turnbuckle tightened so the chainplate is in perfect alignment. I have seen professionally built boats with chainplates that are not lined up with the shroud and it DRIVES ME NUTS. (sorry for the outburst)
The spreaders on an off-shore sailboat must be as strong as possible. Check your spreaders and see if they are merely rivetted individually to the sides of the mast or if they also connected to each other through a compression post so that the lateral pressure is transferred to both sides of the mast. Don’t be tempted to use aluminum rivets. They are easy to work with but you need the extra strength of stainless rivets. One of the easy ways to get spreader strength is to have the spreaders made of heavy gauge tubes and have a rod that just fits the inside diameter and connects to both the port and starboard spreader. You have just increased strength and provided the needed effect of a compression post.
What was the cause of the turnbuckle failure which brought me a DNF and forced me to buy a new mast for my quarter-ton racer? Even though the turnbuckle was the exact size needed for the exertion of the lower shroud, the aftermarket replacements for the threaded pistons in the turnbuckles were made of brass rather than bronze. The brass, of course, way too soft for the job. I assumed the machine would know which metal to use. Oops!