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Volume vs Width vs Length

People measure boards on each of these factors - volume, width and length.

Longboards tend to be long (> 290 cm) , narrow (around 70 cm) and high volume (more than 200 litres). Some of the earlier ones were displacement hulls and as such - did not plane.

These criteria of length, volume and width are particularly of interest when it comes to short boards.
As noted further down ... at first, length was the deciding factor in board measurement , then it was volume and now width. Length has become the least deciding factor ... These are planing hulls - all out of the water ...

Length seems to be related primarily with manoeuvrability. For jibing in particular, a tighter arc can be cut with a narrower, shorter board. From what i have seen, length can actually impact earlier planing as well. A longer, wider board seems to go onto a plane naturally with less pumping. A longer board is easier to tack and will not sink the nose. Short boards, as the name implies have become shorter than the earlier boards. The tendency seems to be wider and shorter boards as we go forward.

Volume is typically linked to flotation. How many pounds/kilos can a board comfortably float?  A rule of thumb for flotation is take your weight in kilos and add 30 for minimal flotation. In my case 100 kilos + 30 = 130 litre board will float me fine and the sail can still be uphauled without too much difficulty.{For beginners some people suggest MANY more litres and a centre board to ensure you get back home i.e. long board}
The more volume also suggests more weight in the board itself. They are finding ways of keeping weight down just the same. The more volume means more area and thus either length and/or width is increased... Without enough volume schlogging becomes sinking :-)
For volume reduction on the freemoves, they have made them thinner and some have cutouts which reduces volume and is supposed to increase speed.

Width is typically related to earlier planing - for short boards. The prime example are the 100 cm wide formula boards. My 94 cm free formula is 170 litres and planes earlier than my 80 cm 160 litre free ride board. If a board is really wide it will plane in light winds, butt will become a handful in chop and probably cannot function well with smaller sails than 8-oh {other than perhaps for learning purposes}.
Another pay-off is the jibe/gybe. A wider board may be more difficult to jibe or require quite a large arc. Thus width is a factor in manoeuvrability.
A wider board will typically be wider OFO/one foot off the tail and thus handle bigger fins. Bigger fins mean bigger sails and early planing.
For the speed freaks - the boards tend to be narrower. The speed needles of the day looked like water skis !!! However, this depends on the wind strength. In the light to mid winds, the formulas are unbeatable. Some wider slalom boards like the SB Isonic and UltraSonic have wider versions that can compete with the Formulas.
A narrower board seems to handle chop better...

In around 2011 RRD came out with a board called FireMove which became known as a "freemove" board. As well as additional width, these boards have less "thickness" which also results in less volume. They are saying that such wide, thin boards actually behave like freeride boards that are 10 to 15 liters more in volume. What is also surprising is: they are saying that these wider, thinner boards can handle chop better than one would expect from such wide boards !!

When I began shortboarding, my first criteria was volume for flotation and then width to ensure the board could handle an 8.5 and the associated fin. When I started looking at early planing, I tried larger fins and sails, butt that did NOT cut it for me. The wider 94 cm Free Formula board put back the FUN in light winds with a shortboard. As my FreeFormula is early 2000's, it is quite long and not that fast. Now the board to beat is was the SB UltraSonic of 93 cm width  / now Exocet RS-7 which is 90 cm, butt are  much shorter than my BIC Techno Formula. The BTF is 267 cm and the SB US is only 240 cm long/ Exocet is 232 cm long. Tinho Dornellas of Calema in Florida feels that such a length is a "JOKE" - especially for heavyweights. John Ingebritsen, also of Florida suggests that 260 cm is the magic length for certain types of boards- for "typical wave sailing".

There are many other important factors in board selection {obviously}. Rigidity or stiffness {for the pros :) }, rocker/bottom shape, rails/thickness, tail width and now even cutouts all affect board function and performance.

For me up until now the key factors have been volume and width. I sail in light to mid winds and do NOT perform high speed gybes. Nor am I a speedster, wave sailor and bump n jumper.

Experts can sail anything in almost any conditions. I am a heavy weight average joe in light wind conditions trying to have as much fun on the water as possible.  My next aim is at speed in the footstraps. Then i will see what the major criteria are there in that category ...

http://www.windsport.com/level_1_beginner/

When it comes to learning how to windsurf there is no doubt that "bigger is better" when it comes to your first day on the water. You will always find three measurements associated with windsurfing boards: LENGTH, WIDTH and VOLUME.
 
A windsurfing board's LENGTH is the least important stat of the three in today's shapes. However, one important aspect of length is that longer boards tend to go "straighter" more easily making them easier to head (or point) towards and desired destination point. If you are a beginner with OK balance or are somewhat athletic you may want to choose a beginner board that sacrifices a few centimetres of WIDTH for a slightly longer length.

The WIDER a beginner board the easier it is to balance on. The only down-side to width is an overly wide and super-short beginner board will tend to "drift" downwind as you sail. This makes it harder to steer back to you starting location. However, if you know your balance is bad than choose a super-wide board and you will have way more fun during your first few sessions... even if you have to walk back up the beach home!

Volume is important as it will tell you how easily a board floats on the water. When choosing a beginner board by volume make sure that the measurement is high enough to support your weight. 

http://www.boardseekermag.com/windsurfing-equipment-tests/test-introduction.html

It used to be simple. A board was chosen based upon its length. Then the importance of volume was recognized and the emphasis changed. Over the past few years, there is a movement towards scaling boards based upon their maximum width. It’s fair to say that it has all got rather confusing!

So here is a bit of theory and we promise to stop after this! The 'useful' size of a board changes depending upon whether it is planing or not. 

When not planing, the size of the board is determined by its volume. This is the weight which can be floated on a board. A 120 litre board will support roughly 120 kilos of weight (including the weight of the board itself and the rig it is carrying). So if you weigh 80kg and the weight of your board and rig is 20kg, you will need 100 litres to float.  A 120 litre board will give you 20 litres of positive volume.  If you plan spending time off the plane, we would reccomend a positive volume of at least 20-30 litres.

When planing, the size of the board is a product of:

         1. The planing area (the bit in contact with the water)
         2. The speed the board is travelling at (the faster it goes, the bigger it feels)
         3. The angle the board is travelling across the water (the more the nose is trimmed up, the 
             more ‘lift’ the board will generate and the bigger it will feel).


So in short, any measure of size such as length, volume, width or otherwise is only ever going to be an indicator, because its impossible to calculate the 3 factors above at any given time. Our advice is to pay attention to the volume, particularly if you are planning to spend some time off the plane (eg uphauling etc) and then look closely at the sail size recommendations of the board. This will give you the best idea of how the board will fit into your quiver. 


JAN/FEB 2003 WindSurfing Magazine had an article on "What can you learn from board specs?

Length - fit in your hatchback ??
Volume - alone is not indicative of anything ...
Width - depends where width is ...
Kind of ironic cuz then they went in detail about OFO, Vee, Tuck, Rocker, Rise , Release, etc ...


I came up with this chart ... with factors versus performance - still a WHIP {work in progress}

https://skydrive.live.com/?cid=C6DB8ADE6B0C768C&resid=C6DB8ADE6B0C768C!462&app=Excel#!/view.aspx?cid=C6DB8ADE6B0C768C&resid=C6DB8ADE6B0C768C!462&app=Excel

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For quite some time I felt that each board had a sweet spot for sail size. At first I thought is was volume based and I created this sheet:

https://onedrive.live.com/view.aspx?resid=24A66D5FF157BE39!132&ithint=file%2c.xlsx&app=Excel&authkey=!AN2YM0c940x9IU0

After some time, I realized that width was becoming a factor and added that column...

A certain board width then also seemed to have a sweet spot for sail size.
The sheet is "old" and thus I decided that 70 cm would be ideal for 7-oh, my 63 cm wide 124 liter Fanatic BEE LTD seemed ideal with a 6.3 sail. The pattern seems evident especially when confirmed with my 79 cm wide AHD FF 160 large shortboard that i preferred with an 8.x sail.

Take the boards width and divide by 10. (ball park and take with a grain - 100 cm = 10 ??)

This idea / relationship is confirmed in the following article.

http://www.surf-magazin.de/test_technik/basics/kaufberatung-breite-wichtiger-als-volumen/a3941.html

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