mast measurements

cflscorpion

cflscorpion

New Member
currently have a phantom & a sunfish and i took a bunch of measurements to see how the two stack up. from the transom everything is the same except the mast step. on the phantom it's 2.5 inches farther forward. any thoughts on how this may/may not effect the way the phantom sails? is this a good thing or a bad thing?
 
Your comparing apples to oranges, two different boats with different rig dimensions and sail area can be expected to have their masts situated differently. The positioning of the mast has a bearing on the boats handling characteristics, a mast that is located too far aft is going to create excess weather helm, too far forward, too much lee helm. Ideally the mast is located so that the boat has a manageable degree of weather helm. Odds are that the mast on each of your boats is correctly located for that particular boat. There is no need to re-position the mast unless for some unknown reason the boat is exhibiting excessive helm, either weather or lee.
 
zeppo, your right. the sail on the phantom is a little bigger than the sunfish. id never change anything. the phantom is almost an exact knock off of a sunfish so i wanted to know why the mast was more forward. the phantom sails fine. just wanted to ask
 
Some time ago, someone sent me a diagram with the geometry for figuring Sail Center Of Pressure in relation to the Dagger Board. If you can find the diagram you can do the math and see why things are the way they are. My guess is since the sail it slightly larger than the SF, the Center of Pressure is in a different spot than the SF. If the boat sails true without Lee Helm or excessive Weather Helm the designers got it right, which I'm sure they did.
 
cflscorpion, I'm not familiar with the Phantom, but if the boat is dimensionally the same as the SF then it's larger sail explains why the mast is further forward. If the mast were postioned as per the SF the center of effort would be further aft, thus creating a bit too much weather helm. There is a keel boat called a Nonsuch, it has a free standing mast with a massive main sail attached to it, to counter excessive helm the mast has been situated well forward of the point of most keel boat masts. (almost like a windsurfer)
 
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