AKA “Marc Tarp”
To protect our Nonsuch 30 Classic “Corvus” from the elements when it is in the water, Marc B (sailmaker) and I (assistant) designed and made a cover that fits under the full length of the sail cover. It protects the brightwork from the sun, keeps the rain and bird poop off the deck and cockpit. When we are on the boat at the dock, the sides opens up or can remain closed. Putting the Marc tarp up or taking it down takes one person 5 minutes. Because it restricts movement on the foredeck and blocks visibility from the helm, we only use it when docked, maybe when moored but never when anchored in case the anchor drags.
The cover is made as one big flat piece, excepting the ridge along the top centre to hold up the cover. The ridge is folded material. Every grommet has polyester reinforcement pieces, grommets could be #2 or #4 size.
Grommets on the ridge fore and aft have short dacron braid lines with stainless clips to clip to the mast and clew, although the clew clip can be directly on the grommet.
More grommets on the top ridge align with the lazy jacks. Each of these grommets has a dacron braid line through with stainless clips at each end to clip to the lazy jacks, allowing the cover to slide on the line as the boat moves slightly at dock and the wishbone moves.
More grommets line up with each stanchion and midway between. Short shock cords and plastic hooks clip to the lifelines, either uppers or lowers. The shock cords are knotted behind plastic washers to keep them from going through the grommets. A YKK #10 zipper on each side roughly aligns with the gate in the lifelines, to allow either side to be rolled up out of the way over the cockpit.
The material is 19 yards/17.5m of Odyssey III (Marlin Textiles, acrylic coated woven polyester, 300 denier, in 64″/1.625m width). Plans in PDF format are here. The whole cover is done as a one flat sheet, cut to width to fit the lifelines, accomodating the rise along the top ridge.
DISCLAIMER This worked for me but may not work for you. Boats can differ, modifications may have been made, you may a Friday afternoon boat (when everyone just wants to go home). Measure and check then measure again before even thinking of using the above plans.
