Date: 12/13/2010
Name: Stephen Jensen, Fleet 1
email: charmedjuan@comcast.net
subject:More on Mast rake
I have been going back and forth on the mast rake for many years. To start with, the masts on our boats are not all in the same place. Most boats have the aft edge of the mast 99.75" from the fore stay tang. Some are at 98.5, while others are 100.25". Add to that, early boats had a shallower keel angle, and a lot of our boats have the keel pivot hole so worn that the keel angle is not consistent on later boats.So, with all this, the method of measuring mast rake and applying it from one boat to another is suspect. The plumb bob method can not be used from one boat to another because the you can't be sure if the weight of one boat to another is the same. An outboard in the back, an anchor forward, and other things inside can alter how the boat sits in the water. How tight the shrouds are puts a pre-bend in the mast, If the Stays are raked aft, that increases the pre-bend. etc.... The fore stay length method doesn't work because the mast placement can be different.
Raking the mast too far aft will hurt pointing and makes getting beaned by the boom much more likely.
You have to sail the boat to check.
My boat has the 99.75" mast placement. My keel angle is at the correct dimension per the hand book. I set my fore stay to the 24'4" as a starting point and have been happy with that. I was thinking about lengthening it 1" but I will have new sails for next year so I'll look at it then.
Yes I have lee helm in light winds. Falling off a little corrects a lot of it. Moving weight forward, increasing heel, and powering up the main also helps.
Charmed Juan has a reputation for being one of the best for pointing boats in Fleet 1. Raking the mast too far aft makes it so I can't point as much
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