Sunday, October 25, 2009

Sail Power



I had long wanted to gain experience with the sprit rig and to find out how adaptable it would be for outrigger sailing canoes. I had brought two sails with me to Fiji; an 89 Sq Ft sprit sail cut out of an old beach catamaran sail and a small 46 Sq Ft triangular sail for high wind sailing. The bigger sprit sail had a row of reef points that allowed it to be reduced to 63 Sq Ft. All three sizes were used quite a lot. It is possible to reef the big sail at sea, but it is a precarious undertaking because you do have to stand up on the foredeck to lower the sprit to the new position. Fortunately there was always a small island nearby that allowed this to be done more easily on the beach. No doubt with a few more tracks and blocks etc, it could all be done without standing up on the deck, but I was trying to keep it all as simple as possible.
Once the sail is reefed down, it is possible to reduce the area even more by removing the sprit all together and pulling the peak down and wrapping it around the mast. This only seems to work well when the peak is pulled to the leeward side and means that you have to change it if you tack. With this in mind I decided to have a dedicated high wind sail and with the frequent 25+ knot days, I think it was a good decision.




My first main sheet arrangement used a cam cleat mounted on the block. These are nice because they take all the strain off your hand and only need a lift and a jerk to release them. I guess I'm a slow learner because I've capsized in the past because of these things. The 1.5 seconds that it takes to release the sheet is still not as quick as an outrigger can put his ama well up into the air. I didn't capsize this time but came close enough to say " this is enough" or "I'm too old for this sh*t".



You used to be able to find "snubbing winches" in marine hardware catalogs, but I haven't seen them lately. So I made a "snubbing cleat" and mounted it on the aft crossbeam. It's carved from 2" wood and allows a single or double wrap of sheet line around its base. With a single wrap, it will slip when you release it, but relieves the strain on your sheet hand while you're holding it. I had no more close calls after this was installed and will only be using cam cleats for less critical tasks.

8 comments:

Anonymous said...

Hi Gary,

The sprit sail treatise and the snubbing cleat description were great. Can you suggest a good resource for cutting a sprit sail for draft (darts and/or curvature)? Alternatively, would you share what you did to ensure the right draft when recutting the beach cat sail to become your Fiji sprit sail?

Thanks, Keith

Anonymous said...

Hi Gary,

Have you ever tried a ratchet block to reduce the effort of holding the main sheet. Something like this http://www.ronstan.com/MARINE/range.asp?RnID=334

Cheers, Tim

Gary.Dierking said...

I had a nice big rachet block here at home, but did not have it in Fiji. I'll be buying one to take with me next time.

Gary

Gary.Dierking said...

The sprit sail was originally off of a beach cat and I did no more than trim the top and bottom, and put some hollow in the leech. I left the luff alone and the draft seems just right.
"The Sailmaker's Apprentice" shows how to make one from scratch.

Gary

Anonymous said...

Hi Gary,
could you tell me if there is a real difference between your Wa'apa and Tamanu boats ??
I made pages about your boats on the french catalogue/forum Nauticaltrek, but I not sur of my classification. For instance, the boat called "tamanu trimaran" on '/homepages.paradise.net.nz/garyd/Tamanu.html' is presented as a Wa'apa in your book (p 37) :'(

Help !!!

Eric, from France

Gary.Dierking said...

The Tamanu differs from the Wa'apa with increased freeboard and self bailing cockpits. it is intended to handle rougher offshore conditions. The stern stem is also more vertical than the bow to take a stern mounted rudder. It is 6M( 20')in length and not built in sections like the Wa'apa.

Anonymous said...

OK Cheif, thank you...

But the "Team RAF" trimarans (2007 Everglades Challenge) are presented as Wa'apas ?? Is it an intermediate design ?
Eric

Gary.Dierking said...

The RAF team built from the Wa'apa plans but modified several things. It was built in one piece, decked over with kayak style cockpits and had a slightly larger sail area.