Having a balanced quiver is vital to maximizing your time on the water versus your local conditions. Very often boardheads, like you and I, have overlaps or gaps in our sail quiver which cause us to either spend too much money on unneeded sails or not having fun due to not have the correct sail size. Although being overpowered can be a rush, being under powered could bring you to the point of suicide. Choosing a balanced quiver comes down to simple mathematics.
ARGH!, Math! You all say... Well it really is quite simple if you have a calculator handy. First you must decide how many sails, what sail sizes you wish to cover, and your main sail which to build your quiver around. If you think that having balanced quiver means having sails that are all one square meter apart, you are wrong.
For example try the following:
1 - 4.0 / 3.0 = 33%
1 - 5.0 / 4.0 = 25%
1 - 6.0 / 5.0 = 20%
1 - 7.0 / 6.0 = 17%
Notice that the gap between a 3.0 and a 4.0 is 33%, but the gap between a 6.0 and a 7.0 is 17%. This is not balanced. You want to choose sail gap sizes that are all the same. (ie. all 20% or all 15% ...)
This can be accomplished quite easily by first choosing your main sail size. For this example lets choose 6.0 as our main sail. (ie. the one we will use most. ) Next lets choose a 15% gap for our sail quiver because we are into racing and want to cover the spectrum of conditions. Now just multiply the 6.0 by 1.15 (the .15 is the percentage amount, the 1 carries the previous amount. Just like sales tax. REMEMBER to round to the nearest tenth, 5.22 = 5.2 and 5.25 = 5.3) That gives us 6.9. This is the next sail size that would create a balanced quiver. Next take the 6.9 and multiply by 1.15. That gives us 7.9. This is the next sail size. Now lets compute our sail sizes that are smaller than 6.0. To do this just divide by 1.15 to get this result. This comes out to 5.2. Now divide this by 1.15. This comes out to 4.5, so on and so forth ... Now you have a balanced quiver.
The next step is finding the right sail sizes. All sail manufacturers do not make sail sizes in 0.1 increments so you need to locate the sail sizes that most closely match your quiver on paper. This may take some adjustment but don't worry about plus or minus 0.1, if it is more than 0.1 than you may need to shift the whole quiver, to fit a particular brand. Thats ok though because as long as the gaps are uniform it is ok.
Here are some example sail quivers and uses.
Wave Quiver: gap(10%-13%)
(10%) 3.0, 3.3, 3.6, 4.0, 4.4, 4.8, 5.3, 5.8 (Ideal-Wave)
Slalom Racing Quiver: gap(13%-17%)
(15%) 3.0, 3.4, 3.9, 4.5, 5.2, 6.0, 6.9, 7.9 (Ideal-Slalom)
Slalom Quiver: gap(17%-22%)
(20%) 3.0, 3.6, 4.3, 5.2, 6.3, 7.6
Budget Quiver: gap(22%-25%)
(25%) 3.0, 3.8, 4.8, 6.0, 7.5
With any of the above quivers you just can't go wrong because you have mathematics on your side. When you start using a more balanced quiver it becomes apparent that it is more important to have your gap sizes evenly spaced out than the actual sail sizes. It just doesn't matter if you build your quiver around a 5.5, 5.7 or 6.0, as long as the gap sizes are uniform. Give this method a try and you will not be disappointed. You will find you will enjoy your time one the water more and not have to worry about having the right sail.
So RIG UP!