Sunday, February 7, 2016

Lug Sail Melonseed

As promised, a short dissertation on the balanced lug mainsail rig is today's fare. When I designed this style of traditional rig for my faering, Saga, I'd never used one. The superlative sailmaker, Lynn Fabricant built that wing with her subtle magic and the little faering fairly flew.

It was an easy sail to set up and use. The balanced lug rigging I use is helpfully documented by Mik Storer in his rigging suggestions for the famous Goat Island skiff, a link well worth exploring for many reasons.

He says this simple and effective rigging comes from an old book, "The Dixon Kemp Manual of Seamanship". The only difference for me is that I don't lash the boom to the mast. I find the downhaul keeps the sail tensioned perfectly whether the boom rests against the mast or not.

With this set-up, I can strike the rig, bundle yard, sail and boom along the thwarts and be ready to row in a couple minutes. In Saga, I even have a long bag to contain the whole mess so it's ready to set anytime.

I use the sail/boom/yard bundle to hang my tent when needed. It's slick. Of all the traditional sail rigs, it's hand's-down my favorite.

The sprit rig on the other hand has not been friendly to me. When I designed my version of the historical melonseed, I drafted the sprit rig as the default, as documented by Howard Chapelle. That was four years ago (where the time went is a mystery). The Doryman Melonseed has been used occasionally as a row boat, for which it is particularly suited, but the sail rig has hung in suspension. Last winter I sewed the spritsail but as you all know, several other unexpected emergencies interrupted my plans. Meanwhile, in the intervening months, I did have a few educational escapades with another spritsail. Not a sail for open water in my opinion.

There, I said it.

Recently I unlaced the spritsail from the mast, fashioned an upper yard and installed grommets along the head of the sail, to lace the two together. The yard is longer than usually specified because I intend to use it in converting another sail to the same design (same type of refit, as well). Of particular concern was the placement of the sail in relationship to the hull. The balanced lug tends to set forward of the mast a bit, which could potentially create lee helm in the original design. As can be seen from the photos, this was of minimal concern in the final analysis.

A difficulty yet to be addressed is the geometry of how the new lug lowers the sail on the mast. I do not intend to carve a new mast, but the sail needs to clear the deck by an additional 4-6 inches. Obviously there will be no room for the required downhaul on the tack, but with the extra long yard, the opportunity to tension the head of the sail with a downhaul on the forward end of yard itself is apparent.

I like the way this design allows for changing the angle of the yard. The balanced lug tacks best to windward with the head peaked-up as high as allowed. Running off the wind, the yard can be set more horizontally, to provide more power.
Note how lacing the halyard from the forward end of the yard, through a block midway on the yard and thus through a sheave at masthead tensions and binds the yard against the mast. You will notice the halyard leads to the cockpit from the base of the mast (above).

Both the downhaul and the halyard are then lead through the coaming, to cleats in reach of the helmsman. This sail configuration can be set and struck from the safety of the cockpit, the solution to my concern about the sprit rig, which is a bear to strike in any kind of real wind.

 This series of shots show how easy it is to lower the yard into the boat and the halyard lacing option used allows the whole kit to be stowed on the thwarts in seconds, allowing the mariner to concentrate on other matters when necessary. Thus stowed, the sail is also ready to set at a moment's notice. When it's time to stow this rig, the yard, sail, halyard and downhaul stay together in a handy bundle. The mast is bare and easy to handle.

For now, this rig has no boom. There is no particular reason for that other than expediency. This will hamper off-wind and downwind performance, though how much remains to be seen. A test sail is in the offing.

In a small boat, simple is best. I would add, this principle applies to larger boats (and life in general), but that's a topic for another day...


EyeInHand said...

You're right about the challenges of dousing a sprits'l on the water, particularly on a cat rigged boat like the Melonseed with the mast way up in the eyes of the bow. On the smaller 'seeds it's basically not possible to go up there and lower sail alone. For open water sailing, even distance solo sailing in protected water, you have to plan your crossings very carefully. While able to stand up well to a pretty good blow, once you've committed there's no way to adapt or bail out. Nothing to do but hold on and bear off for cover as fast as you can. For more than day sails you need a more adjustable rig.

An opinion based on my own experience and tolerance for risk. I'll be following your experiments with interest.

doryman said...

Risk is the name of the game. Speaking of... this sail needs some reef points. Probably take a calculated risk on a mid-winter sail first. Waited long enough already. Thanks for your interest, Barry. Where would I be without you?

Unknown said...

With the way you have the sail rigged, although you have the lug yard, the sail itself is actually rigged more like a gaff rig, and I imagine performs rather more like one than a lugsail ?

doryman said...

I suspect you will prove right, Matt. The tack of the sail will be fixed to the deck at the base of the mast, thus limiting the balanced nature of the lug. The head of the sail will no doubt move forward of the mast a restricted amount, of little importance to this discussion. The advantage to the lug sail over the gaff will be in it's portability when doused. This is most important when shifting to oars and my hope is that this melonseed will perform at advantage, as a sail-and-oar cruiser.

Diana said...

Intrigued. Would like more pictures of the balance lug bundle used as a ridgepole. I've been puzzling in my mind to rig something similar on my Phoenix III. Beautiful website/blog, BTW.

doryman said...

Yes, it's a puzzle. With the halyard rigged to approximately mid-point on the yard, it's problematic to use with a boom tent. On my Valgerda (Saga), I rigged two additional halyards specifically for that purpose, which I use on each end of the bundle to set it up as a ridgepole. The mainsheet guys it down. I sleep on the floor-boards, amidships.