MacGregorSailors.com

New to site. Kool. Answer to question regarding measurement for Spinnakers. Reference Sail Power by Wallace Ross. Class racing rules are very strict on this subject. It's a Formula. I x J x 1.8 = square footage. "I "is the height of the mast from the foredeck, not the mast step which sits atop raised cabin, If masthead rig. Otherwise height of forestay if fractional. "J " is the distance from the forward base of the mast to the tip of the bow or bowsprit. example: Venture 25 masthead rig. I = 29 ft 4 in J = 10 ft. 29.3 x 10 x 1.8 = 527 sq ft +/-. I rigged my masthead V-25 10% oversized for ocean racing (i.e. Ensenada.) = 580 sq ft +/-. This incurs a PHRF handicap penalty, 240 to 228, but boy what a rush!! See picture of Freedom77 on Sailboatowners.com site. I will try to post pics on this site. The spinnaker pole is the "j" dimension. Need mast attachment with ring for pole on mast with track. rig block aft of forehatch with pad eye for foreguy/downhaul, reinforce with heavy metal backing plate under deck. Spinnaker sheets twice a long as the boat. Will need swivel turning blocks with under deck plates as far aft as possible and a good set of winches. Nothing can ruin your day more than having a piece of deck hardware rip out and turn into a missle. Also think about a reaching strut. will need strut eyes on each side of mast. Keeps the sheets off the shrouds when close hauled. Make sure spinnaker halyard block is swiveled. Keeps from wrappng and hourglassing. Spinnaker launch bag a must.$$$$ You may get lucky and get a stock used sail from Hood or North at a decent price. Hope this wasn't TMI. There will a pop quiz later.

History of Spinnakers: In the old days when the rich dudes, Astor, Lipton, etc. sailed "J" boats there was a big monster named Sphinx. It was the first to hoist what we now no as a spinnaker. It was so big it was called Sphinx Acre, and thus spinnaker. Fair winds and Full Sails... Old Salt.

A Sailboat is a hole in the water into which you pour endless amount of money.

A sailboat is like a woman. The rigging costs more than the hull. Plaque permanently affixed in our cabin by Penny Sue.

An asymmetrical spinnaker (A-sail) delivers most of the performance and all of the beauty of a regular spinnaker with a fraction of the effort.

This is what you need to fly an a-sail from your Mac:

An a-sail
A tack line; about ten inches of line shackled to the forestay base
Sheets twice your boat’s length, about 100 feet total
A pair of turn blocks for sheets
Your existing jib halyard and pulley will work fine, but a swiveling pulley is a bit better

This is what you need to rig a spinnaker:

A spinnaker
A pair of turn blocks for sheets
A pair of turn blocks for guys
A downhaul with a turn block at the bow and fair leads to the cockpit
A topping lift
A spinnaker pole
A pair of sheets
A pair of guys (not men, lines used to control the pole side of the spinnaker. Guy lines are fun primarily for the rude humor possibilities they inspire, especially if you have a crewman named Guy)
A mast track or pad eye for the pole
Halyard
An extra crew person to fly the sail
Food and drink for extra crew

My latest Youtube video, Meet My Boat 3, shows how to rig, fly, raise and lower an a-sail on my 1998x. With some practice, it’s easy to fly the sail single handed and it moves the boat very well in light air.

http://www.youtube.com/watch?v=3OxykDlvc1M

Of course, this post could be seen as just another shameless attempt to promote my Youtube video…

Thanks Markdartist, Assymeticrals are great. I guess I'm old skool or don't want to shell out for a new chute. Where can you get a stock chute for a Mac? Fair Winds and Full Sails... Old salt.