Your editorial regarding weeping foam-core rudders brought to mind my own experience.
When my Tartan 30 was surveyed prior to purchase, we found that the rudder was seriously delaminated. I called Tartan to inquire about a rebuild. They were extremely courteous and helpful. Price: about $875 “if the rudder post itself is in good shape.” If not, I was looking at about $500 more.
The yard in which the boat was stored—Barlow’s Boat Yard in Pocasset, Massachusetts—said they could do the job for less. Now I was in a bit of a quandary. Cost was important, but wouldn’t the factory do a better job?
The matter was settled when we dropped the rudder. The skeg fairing had hidden the cause of the problem—a split along the entire length of the leading edge of the rudder. When I saw that, I didn’t want another rudder that could do the same thing. This feeling was amplified when the yard cut into the rudder. The foam core was still soaking wet (the boat had been hauled out for two years). It crumbled in sodden, stinking clumps to the shop floor. And as might be expected, the areas around the steel tangs welded onto the rudder post were greatly compressed. Okay, it is a 20-year-old boat, and things wear out. Still, it surprised me that a boat that was clearly otherwise extremely sturdy and sound would rely on a rudder system that could fail in this way.
Jerry, the fiberglass whiz charged with the repair, came up with an ingenious solution. He cut through the glass on each side, leaving about a 1/4" strip of original around the perimeter, so that all that remained of the original rudder was the post and the outline of the remainder. Next, he routed out everything that remained and cleaned it. After making sure that the welds on the plates were in good shape (they were) he began laminating stepped layers of 1/4" marine plywood. Special shims were cut to ensure a tight fit around the tangs. The steps were then ground to return the rudder to shape.
Next, the rudder was covered with four layers of woven glass, faired, given three coats of epoxy primer and painted. Because of the glassing and fairing, the new rudder is a wee bit bigger than the original. And it’s heavier than a dry foam core rudder would be. Total cost was $850. Not as much savings as I’d hoped for, but the rudder will in all likelihood be the last thing on the boat to fail.
Cross-Country Boat Move
To add a note regarding the April 1 letter about boat moving, I shipped my ComPac 33 to the Pacific Northwest last year. The move from New Bern, North Carolina to Bellingham, Washington cost about $6,200 for the transportation, plus about $700 for the preparation out of and into the water. The process of selling and buying was not considered because of the time it would take.
The mover, Dallas & Mavis of Jacksonville, Florida, was not the lowest bidder, but seemed to be the most responsive of those that I contacted. They loaded on schedule while we were on the road out west and delivered on time with no damage. This was a very positive experience.
Albert L. Chasson
Raleigh, North Carolina
Rigging: How Tight?
In the July 15 issue, you posed the question concerning rigging, “How tight is right?” This question needs a well thought-out explanation. Unfortunately, one was not forthcoming. The answer is based upon concepts that when understood yield the number. In this case, the number can be a percentage of breaking strength or safe working load. It depends exactly on which shroud you’re dealing with and why it may be different from the others.
Rigging tension can go from 35% to 70% safe working load, depending on circumstances.
The idea of “stress pre-load” comes into play. If the wire rope, or a bolt, or side force on a bearing race is pre-loaded to its normal expected working level, the force applied absorbs outside forces within its pre-load. The external stretching force is less than the pre-load and is absorbed in it. When this occurs, the material stretches only to a minor degree and can return to its previous size.
If this pre-load condition does not exist, the outside forces acting on it will shock load the material, causing stretching past its modulus of elasticity, leaving permanent distortion.
This is why pre-loads are set into wire rope. Typically, 70% of the expected safe working load is where to set the high end.
Breaking strength should not be used. Theoretically, failure can occur anywhere between the highest safe working load figure and ultimate breaking strength. The probability of failure increases dramatically as you exceed safe working load and head toward the breaking strength, with failure almost certain at breaking strength. The safe working load of wire rope is about 25% of its breaking strength. Although it would be extremely tight, 70% of safe working load is only 17.5% of breaking strength.
The most common cause of rigging failure may well be rigging that is too loose, for the reasons you suggest.
Simple rule of thumb: On a beat in strong breezes, the leeward shrouds should not be noticeably slack. You may see them slacken but they should not be blowing in the breeze!
The backstay tension can be set at about 40% to 50% SWL, and show about 6"-8" of forestay sag under moderate breezes. Do not try to eliminate forestay sag.
Monroe Township, New Jersey
Roller Furler Safety Lanyard
Nearly every year I see jibs and genoas flogged to destruction due to breakage or lack of secure fastening of the furling control line during high winds while the boats are on their moorings. Boats have been severely damaged after their headsail unfurled and they “sailed” back and forth until their mooring pennants failed.
It’s considered prudent to tie a short line or sail tie around the furled sail as high as can be reached above the deck whenever a boat is left unattended at anchor or on a mooring.
I have been using a better and easier method. It consists of simply permanently attaching a short, strong line to the bow pulpit or other convenient location near the furler with a snap-hook or shackle on the other end of the line, which can be hooked to the tack fitting on the top of the furler drum. This positively prevents accidental unfurling, yet allows quick and easy disconnecting and stowage of the lanyard back around the pulpit or itself when you are ready to set sail.
Pearson 28 Cockpit
In the upper right photo caption on page 5 of the July 15, 1998 issue, you describe several features of the Pearson 28 (“Bench Warmers Beware”). You are accurate in describing “the nicely contoured and well-rounded cockpit and coaming seating on the thoughtful design” of the boat. The seat-to-seatback angle is perfect.
However, you inaccurately describe, “What looks to be owner-installed line storage adjacent to the companionway.” This line storage was in fact factory installed. It doesn’t prevent using that surface as a backrest, but it sure makes it uncomfortable. We just hand a cockpit cushion to the person sitting there.
St. Peterburg, Florida
The line storage ruins the best seat in the house. No cockpit cushion can turn that into a comfortable place when it is defaced with a tangle of lines, hooks and gauges.
Where Credit Is Due...
To Windline: “We recently purchased a 59' Alden motorsailer, which has a Windline Universal bow roller. At some point in the past, the bow roller had been twisted. When we redesigned the anchoring system I contacted Harry Newbigging at Windline Marine and described what had happened to the previous bow roller. He immediately offered, at no charge, to reinforce the two new Windline bow rollers I had for the redesigned system. This kind of customer service, along with their lifetime guarantee, is certainly a breath of fresh air to this sailor.”
To B&G: “While sailing in the Bahamas last winter, we had several instances of an unusual failure (sudden hard-over rudder command) of our B&G autopilot. On each occasion, a phone call brought immediate response. Computers, control heads and compass were changed twice at two different locations, within a few days each time. This was obviously at considerable cost to B&G. The intermittent problem persisted. Upon our return to Largo, Florida, the problem was properly diagnosed, not just “repaired.” B&G installed an entire new, upgraded and considerably more expensive system. ‘No charge, and sorry for all your troubles!’ Thanks to B&G Customer Service and Gulfstream Marine, both in Largo.”