Posted by Peter Busby on August 28, 1997 at 03:20:11:
In Reply to: How to rig a lugsail? posted by Jonathan Engdahl on August 27, 1997 at 23:13:59:
SA _Making Ready_ "On the yard there was a strop (which is really a loop) that hooked on a hook on one side of an iron ring called the traveller, because it moved up and down the mast. The halyard ran from the traveller up to the top of the mast, through a sheave (which is a hole with a little wheel in it), and then down again."
_Gaff rig_ by John Leather, International Marine Publishing Co, Camden Maine, USA, also Adlard Coles Ltd 3 Upper James St London W1R 4BP, 1970 - has several drawings and pictures of lug-style topsails. All appear to be hoisted about 1/4 to 1/3 up the yard (or gaff) from the throat.
There doesn't appear to be any rigging needed on a lugsail for it to maintain its aspect (where a gaff rig has throat and peak halyards), so I assume it maintains its shape by the cut of the sail and the tension between yard and boom, as set by the halyard and the downhaul, if any.
It appears, therefore, that your tarp sail must have the correct cut, so that the luff tension is sufficient to raise the peak. You may have to consider some reinforcement along this edge.
I suspect that, since you are not likely to be reefing this sail, and since it is experimental in nature, you probably could get away with raising the yard without a traveller until it is chock-ablock; the halyard would then hold the yard tight to the mast. You may consider a parrel (a cord with a set of large wood beads); I might note that _Gaff Rig_ describes the requisite mast as having parallel sides (even diameter) to the hounds, since this is where the gaff jaws must travel, but then, the book is describing much larger vessels.
At the recent Corroboree in Toronto, my daughters sailed on Snapdragon, which was a small gaff-rigged catboat. She sailed rather handily to windwards - her crew had great fun trying to toss bailerfuls of water at either of the other crews who got too close, to the detriment of some cameras!
My main experience with non-Bermuda rigs is the sprit-sail rig we used on our canoe trips. The advantage to having a square sail with a spar running across its diagonal (from tack to peak) instead of a boom was being able to use the liner from our sleeping bag as the sail - double duty, you see, thus reducing weight over portages.
[By the bye, we sailed (in _Halcyon_, my 19-foot Lightning) around a group of about twenty Common Loons (Great Northern Divers) yesterday, on a lake in the middle of Sudbury, Ontario. They didn't appear stressed by thier proximity to "civilization".]