There is a web site, "Ted's Sailing Page" where in he gets his boat level on his trailer using a water level at the boot stripe.A four foot level,its top against the mast,and a gap of one inch at the bottom will then represent a rake of about one degree.Alternatively,a plumb bob attatched to the mast tip will rest on the deck three inches behind the mast for every 10 feet of mast height.Do these numbers seem accurate? If there is anyone who has a well pointing oday 22 and a four foot level and can check this,it would be of great help.Or perhaps someone who is better at trigonometry and can check the 3inch per ten feet math. LLOYD
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Math time . . . hey, neat
I think your guy has given you a way to find 1.43 degrees, but I thought this is neat. You can find the angle of your mast rake by measuring the distance from the mast to the halyard as it hangs free, multiplying by 4.75 and dividing by the distance from your measurement point to the top of the rig in feet. Proof follows: Some engineer correct but here we go. First, solving for the angle between the mast and the halyard hanging from the mast tip. Mast is 10 feet or 120 inches. Distance mast to plumb perpendicular to the mast, not parallel to the ground, is three inches. I think the neumonic was SOA CAH TOA. So were're solving for the angle knowing oposite and adjacent. So we need the tangent function. Opposite over adjacent is 3/120 = .025 inverse tangent = 1.43. So the angle between the halyard and the mast is 1.43 degrees. The halyard is vertical, assuming gravity is working, so its the mast that's 1.43 degrees away from true. Turing it all around - for every 12" of mast height, one inch of distance from the mast equates to 4.75 degrees. So if you do inches from the mast * 4.75 / feet from the measurement point to the halyard sheave, you get the mast rake in degrees. Hey, neat. Justin - O'day Owners' Web
I think your guy has given you a way to find 1.43 degrees, but I thought this is neat. You can find the angle of your mast rake by measuring the distance from the mast to the halyard as it hangs free, multiplying by 4.75 and dividing by the distance from your measurement point to the top of the rig in feet. Proof follows: Some engineer correct but here we go. First, solving for the angle between the mast and the halyard hanging from the mast tip. Mast is 10 feet or 120 inches. Distance mast to plumb perpendicular to the mast, not parallel to the ground, is three inches. I think the neumonic was SOA CAH TOA. So were're solving for the angle knowing oposite and adjacent. So we need the tangent function. Opposite over adjacent is 3/120 = .025 inverse tangent = 1.43. So the angle between the halyard and the mast is 1.43 degrees. The halyard is vertical, assuming gravity is working, so its the mast that's 1.43 degrees away from true. Turing it all around - for every 12" of mast height, one inch of distance from the mast equates to 4.75 degrees. So if you do inches from the mast * 4.75 / feet from the measurement point to the halyard sheave, you get the mast rake in degrees. Hey, neat. Justin - O'day Owners' Web
More useful way of looking at it . . .
If you multiply the mast rake you want in degrees by the height of the mast from the gooseneck to the masthead truck, and then divide by 4.75 you get the number of inches the plumb bob should hang from the mast. So, if you want 5 degress of rake on a two foot mast, you do 5 *2 = 10 / 4.75 = 2.1 inches of distance. So my more math enable friend concluded that my last post was slightly off because it assumed the halyard was the hypotenuse instead of the mast. This results in a percentage difference equal to the additional length of the halyard as compared to the mast necessary to reach boom divided by the distance from the gooseneck to the truck - he assures me the error is very, very small.
Justin - O'day Owners' Web
If you multiply the mast rake you want in degrees by the height of the mast from the gooseneck to the masthead truck, and then divide by 4.75 you get the number of inches the plumb bob should hang from the mast. So, if you want 5 degress of rake on a two foot mast, you do 5 *2 = 10 / 4.75 = 2.1 inches of distance. So my more math enable friend concluded that my last post was slightly off because it assumed the halyard was the hypotenuse instead of the mast. This results in a percentage difference equal to the additional length of the halyard as compared to the mast necessary to reach boom divided by the distance from the gooseneck to the truck - he assures me the error is very, very small.
Justin - O'day Owners' Webmast tuning
It stalled in irons each time.I will admit to not being an excellent sailor,but when I first bought the boat,I could bring her around just fine.Then I replaced two shrouds,changing around the "settings" the previous owner had,and the results were just bad.I need to get the boat at least in the ball park before I start Fine tuning.The boat came with a 125 genoa,so I had a standard jib made,and she still wont come around with the smaller "normal" jib.I am hoping to get down to the yard and get her level on the trailer and check the mast etc. this weekend.LLOYD
It stalled in irons each time.I will admit to not being an excellent sailor,but when I first bought the boat,I could bring her around just fine.Then I replaced two shrouds,changing around the "settings" the previous owner had,and the results were just bad.I need to get the boat at least in the ball park before I start Fine tuning.The boat came with a 125 genoa,so I had a standard jib made,and she still wont come around with the smaller "normal" jib.I am hoping to get down to the yard and get her level on the trailer and check the mast etc. this weekend.LLOYD
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