Nylon Mainsail Seatrial 3

[capt_nemo]

Seatrial 3 took place today on Charlotte Harbor, Southwest Florida. Purpose was to verify the effectiveness of a few mods I made to the homemade gaff and the "Topping Lift" arrangement to support the weight of the boom and stowed mainsail.

Here is the homemade Nylon Mainsail set "flying" over the boom with stowed Mainsail.





And here is the homemade Drifter assisting on Port Tack.

[Bob23]

Great looking sail, Capt.
   Hmm...I wonder if this will be legal in the next Suncat Nationals?
   Looks like the wind was pretty light so how did it work?
Bob23

[capt_nemo]

Bob23,

Worked quite well. I'm qute pleased with the performance of the Nylon Mainsail, and hope to perfect its use and trim in the future. There are a lot of those "light air days" down here in Southwest Florida when it will come in quite handy. During Seatrial 3 in 2+ hours on the water in really light air, I saw about 6 other sailboats - NONE of which had sails up. I sailed across the harbor and back again, trying different points of sail, and had a really enjoyable day!

I'm still impressed with the performance of the Nylon Drifter especially when flown with the stock mainsail in moderate air. It's hard to believe the additional "Drive" that only 38 sq. ft. of Nylon can produce and the synergistic effect of the two sails working TOGETHER! But then again, as an ex cutter and sloop rig sailor, I fully appreciate the worth of good headsails.

capt_nemo

[Shawn]

Looks good. How did you design the main? Is it just flat cut or did you use something like Sailcut CAD?

Shawn

[capt_nemo]

Shawn,

I'm definitely "old school" when it comes to design and fabrication of the various projects to improve my boat.

It is first laid out flat for the size you want then curvature is built in by adding different sized "rounds" to each of the four straight side edges. When those rounded edges are then straightened by tension when "flying" it induces curvature or "draft" in the belly of the sail. Easy enough to do by hand and quite effective as a simple way to achieve curvature in a sail as opposed to more tedious and complicated panel sewing methods.

Here is a photo of the sewn panels laid out flat on a wooden dance floor ready for measurement and marking.




This photo shows how I used a thin flexible wooden batten to draw the "round" in the foot of the sail. Notice that the maximum depth of the smooth curve "round" occurs approximately 1/3 of the foot measurement behind the tack (located at top of photo), NOT in the middle. Likewise, the maximum depth of the luff "round" occurs 1/3 of the way UP from the tack. Maximum depth of both head and leech "rounds" occur at their midpoints.

[skip1930]

COOL!

I like your lofting idea with flexible batten and jugs at the gym.

skip.

[Joseph]

Capt_nemo,

Very nice. Your seamanship excels even in a dance room. Your native name should be "Dances with Sails"...

In the first picture one can see what you did for three of the sail angles including the tack. How about the clew? and did you rig anything in terms of outhaul?

Again, chapeau.

Joseph.

[capt_nemo]

Joseph,

Yes, you guessed correctly. The clew was attached to the boom using a typical "outhaul" arrangement as shown in the photo below. For trials I simply led the nylon line from the clew thru a round shakle on the end of the boom and forward to the reef cleat on the side of the boom. This will eventually be replaced with a small proper turning block on the end of the boom, low stretch Dacron line and perhaps (haven't decided yet) a cam cleat, another small regular cleat, or just have the reef line cleat do "double" duty. I'm inclined to abide by my usual design philosophy of "use what is already there" if possible, and not drill more holes and add hardware!

[Joseph]

Captn_nemo,

Thank your for your reply. The clew looks classical and simple.

I also noticed the line that you rigged from the top of the gaff to the end of the boom. Being attached to the gaff this could hardly function as a regular topping lift. Am I right in thinking that it avoids the leech from taking the entire weight of the boom and thus allows a more rounded sail shape in light air? If so, it would be closer to a self-standing leech-line than a topping lift...

I could not tell what kind of changes you made to the gaff (which looks partially in wood and slightly curved - perhaps due to the weight of the boom?) but could not help noticing the windex at the top of the mast (which I also bought but never installed from fear - obviously unjustified - of it being caught by the gaff), the intriguing plate that you used to installed the cleats to starboard, and the nice bright finishing that you applied to the woods on deck (Cetol?).

An all accounts, compliments.

J.

[capt_nemo]

Joseph,

Right again. The line from gaff end to boom end does not function as a regular topping lift. It does take the weight of boom and sail off the leech to achieve better shape in the Nylon sail. I still have the original Topping Lift I installed, led back to the cockpit port side that I use until the Nylon Main is hoisted. Then I tighten the line added from gaff to boom and release and stow the original topping lift along the boom out of the way. No slack line to chafe on the sail and much easier tacking. The line added was my neighbor's idea to avoid my having to alternate topping lifts for different tacks. A self-standing leech-line is a much better name for the added line, thank you.

The gaff was made from a relatively strong fiberglass and aluminum telescoping pole used for painting that I found in Home Depot. I thought I needed a pole that could be collapsed for easy stowage down below. And yes, it is flexed due to the peak halyard pulling up in the middle and the self-standing leech-line pulling down from the outer end. I may make another one using stock aluminum boom extrusions. Some close up photos of the gaff follow.

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The curved plate to starboard (one also portside) was installed to avoid drilling, filling, and redrilling holes in the NEW cabintop while I tried different control line configurations. The epoxied and painted curved plywood (2 layers of 1/4 ") is easily removed for changes WITHOUT removing the four 1/4" bolts that hold the base fittings to the cabintop on each side of the companionway.. Here are a few photos.

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And yes, the finish is Cetol Light.

[Joseph]

Captn_nemo,

Really neat how you solved many of the challenges, some obvious, others not so much. Loved your use of the parrel beads for the head of the sail, a detail reminiscent of wooden-mast rigs, and what looks like a top "gaff outhaul" with its own cleat on the side of the gaff.  Thank you for these very creative improvements. Enjoy your unique light-air SunCat!

J.

[Tom Ray]

We need to pick a nice, light day and hold another "Sun Cat Regionals" so we can see how all this stuff stacks up against an old, blown out sail like mine!