July 12, 2011 at 3:47 am #1820
I finally registered so I can join in on the fun here. I would like to initiate my presence by asking everyone who can, I would like to know the distance between the front of your mast at the bottom and your forward bulkhead. This distance determines how much mast rake you have.July 12, 2011 at 2:00 pm #2181
I’ll try to remember to measure tonight. Previous owner had experimented with several positions and I left the ‘last’ one as is. Since it had a good race record, it might be a good starting point.July 12, 2011 at 3:36 pm #2182
If I remember correctly, 24″ even.July 12, 2011 at 10:52 pm #2183
For Kestrel: 24 3/16″
Al HoltJuly 13, 2011 at 2:43 am #2184
Spar Wars #212…. 24 1/2 “July 14, 2011 at 6:42 pm #2185
I’ll measure this evening. What is Ichiban’s measurment?July 15, 2011 at 2:10 am #2186
Ichiban is 24-7/8″July 18, 2011 at 6:07 pm #2196
Andrew, White Lightning is 24-7/8″ alsoJuly 18, 2011 at 10:07 pm #2197
Organized Chaos is 25-1/8″. How sure are we of the precision of the position of the bulkhead relative to the transom? If it isn’t an intended measuring point, it wouldn’t be surprising to find that it varies by as much as 1-2 inches. Manufacturing techniques were good, but not quite up to modern CAD/CAM standards. Would the lifting bolt on the keel be a better reference?
Either way, I’m going to have a hard look at the rake on the boat. Has anyone measured the distance from the top of their mast to the bottom of the transom (no backstay tension)? Having both the position of the mast step and the aft measurement would allow for the most consistent results.October 25, 2011 at 1:31 am #2418
Here are some mast rake measurements from Ullman:
To measure your rake you will need a 50 metal tape measure.
Using a metal tape connect it to your main halyard and hoist
it until the main halyard is two blocked. Measure to the
middle of the hull deck joint where the transom and the deck
meet in the center of the boat (in line with tiller). Pull the
tape tight Take the measurement above and add it to the
length of the main halyard
shackel this should be
between39’2” amd 39’4”
To get the correct rake with
the correct prebend it may
require moving the mat but
Rules of Thumb
The correct amount of prebend varies with the cut of your
sails. Ullman Sails has designed their Olson 30 sails with a
fairly straight mast for optimum performance. If you do not
have Ullman Sails and your sails are very full with a straight
mast you will need to put some prebend in to compensate for
this. Be careful not to carry to much prebend because it will
cause your forestay not to get enough tension and will make
your genoa to full and this will hurt your pointing.November 5, 2011 at 12:59 am #2441
O Naturel, 24.5. Single spreader. Main, the only North 3DR Olson main in existence! The machine had a meltdown before a second one was produced!November 5, 2011 at 3:02 am #2445
My boat used to be a ‘North’ boat..so with all the extra holes in the step board..I think it was dialed in at 24.5. Glad you have a 3DR..because no 3DL’s exist any more either. Mine disintegrated at 4 years old.
I’m thinking with a new Quantum main coming (Todd Downey listening?) I’ll ask Todd where his step is.
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