View Full Version : Sail Size Query
20th May 2008, 04:56 PM
I am about to buy my first kit shortly and am wondering about the sail size I need.
I am 70kg and sail in average of 15mph winds on an inshore lake. It does get windier but this seems to be conditions on a normal day when a breeze is up.
I am able to get planing on some quite old kit when the wind really gets up (definitely in excess of 15mph) using a newish 6m sail.
I am looking at getting a Go, Carve or Futura (whichever comes up at the right price) and in the range of 144litres.
I am only going to be able to buy 1 sail to start with and would appreciate some advice on what size.
I'm thinking of a Tushingham T3 or similar at 7m.
Am I in the right ball park for my board and sail?
I would like to be able to get planing easily but have had difficulty in the past with an 8m sail which felt extremely heavy (though it was using an old sail and old mast which probably added to the weight).
Many thanks for any suggestions on spending my hard earned cash.
20th May 2008, 10:51 PM
I think you are on the right track, but if you keep your "newish 6.0m2" sail (by the way, what mast are you using in this sail?) a 7.0 m2 Tush would not give you the range (light wind planing here) that you could get with the same sail in a 7.5 m2 size.
Since you are only going to have one or 2 sails, it pays to spread them out about 1.5 m2 (above 6.0 m2 anyway) as this covers a much broader range of conditions and there is less "overlap".
Get a 7.5 m2 Tush T-Bird with a 75% or higher (Tush FreeRace 80 would be good) and you would have a really solid rig for up to 18 knots (with some tuning).
If you can only have one sail, then your plan for the 7.0 Tush (again the T-bird on a FR 80 mast) would work as well.
You are looking at fairly wide boards, and boards that have a fairly wide range of use (windspeeds here) so getting a couple more sails (one larger and one smaller like using a 7.0 m2 as your basis then getting a 5.5 m2 and an 8.5 m2) would allow you to use the full potential of your board.
Hope this helps,
21st May 2008, 03:13 AM
Just wanted to make sure I was headed in the right direction. The 6m is not my sail so it looks like I may go for the 7m if you think it will get me planing in the conditions I gave. Will take a look at the 75% mast...the weight difference doesnt look that much compared to a 30-45%mast and as such I wasnt sure if the cost difference was worth it....but then again I have only ever used a 45% mast with around 20cm extension so I havnt been able to compare different ones. Does the little extra weight affect the feel so much? Have only been able to use a small amount of borrowed/hired kit so my experience is quite limited.
Cheers from sunny England,
21st May 2008, 04:27 AM
Get the lightest mast you can afford! Holding the mast on land does not give you a good idea of the difference in weight that using it on the water will provide. It isn't just the heft of the thing as you raise the sail with the mast in it, but it is so much more and it's dynamic. 75% will serve you well, and will be much much nicer than a 30-45%, and will make sailing your gear that much more enjoyable. Get a good mast to begin with and you'll be spending your hard-earned cash well.
(Note: I don't sell anything, but I sail a lot of things and have learned over time to try to do it right the first time.)
cheers (but we are having rather English weather here in New England...)
21st May 2008, 05:17 AM
You've given me a great idea here.
I've always wanted to do a bit of an experiment on how much actual measured force it takes to uphaul a rig with a < 50% carbon mast.........a 75-80% carbon mast,...... and
a 100% carbon mast.
I think that a board (perhaps I'll use the Rio M here) can be used as the "base plate".
Then I will rig a specific sail (probably the new 2008 Retro 6.5 m2) with a few different masts, usng the same base extension, the same boom attached at the same height.
If I weigh each mast seperately, make a little spreadheet of these weights, and then how much force (measured with an electronic scale) it takes to pull that mast up from horizontal.
I think this little experiment will quickly and accurately show us how many times that little bit of weight (You asked "Does the little extra weight affect the feel so much?" )
get multiplied when we uphaul from the wrong end of the lever (ie the fulcrum point is at our feet, and we are pulling on an uphaul line attached 30-40% up the mast).
It's a bit too hot this afternoon, but I know I have a 75% 460 Sailworks Joystick, I can probably find a < 50% carbon 460 Powerex mast of some sort, and I have a couple of 100% carbon 460 race masts.
If I attach the uphaul and boom at the exact same height, I think we can see some reasonalby accurated results.
Thanks for putting me onto this idea.
21st May 2008, 10:37 AM
That would be a nice experiment, I would be looking for your results on this. Does the same rule applies for a full carbon boom compared with a aluminum boom? It's the weight here or it's a matter of more performance because the stiffness of carbon?
21st May 2008, 08:20 PM
That sounds like a great experiment, please keep me informed. I done some searching and I havn't been able to find any information providing a quantitative answer to your idea, so it should be good.
Thanks for the advice, I think I will save a little more cash then and go for the 75-80% mast. It will be very interesting to see what Roger's experiment shows.
28th May 2008, 06:31 PM
How did your test go?
29th May 2008, 11:48 AM
Unfortunately, I didn't do the test the day I hoped to, and now I'm in a teach/travel/work/travel teach cycle.
I'll try to get to it next week when I have a bit more free time.
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