No formula that I know of. There are too many other variables.
The easiest way is to use a CAD program, import an image for the template you’re thinking of, match the CAD design to the image, adjust the rocker in the CAD to approximate that of your target and work of the deck/rail profiles. That will get you closer, but not precise.
My “quick estimate” for volume is to assume the board planshape is an ellipse. Estimated volume would be surface area of the ellipse (0.5 width x 0.5 length x 3.1416) times average thickness.
Why do you need the volume?? I agree it can be useful in a certain context, i.e. when computer shaping or fine tuning a pro board, but trying to imagine a scenario where this number is needed on a finished board, and coming up empty.
Hi Stoneburner, how do you finish with 1.9 inches as the number to use? I do not see how.
Hi Huck; is the same useless thing as the length normally used. It says anything of the board characteristics. There s a plenty of say 5 10 with different characteristics but the people loves to know that stupid measurement.
I have been having problems with that because I do not write those numbers on the shapes.
I prefer to talk in “concepts”. For what is intended that board and for what type of surfer.
However, if I use the 32-L volume OldMW reported for the 20" x 6’0" SB shape. I would assume a 20" x 72" ellipse and back calculate the mean thickness for a volume of 32 L.
Mean thickness is 1.726". The ratio of mean thickness to actual thickess is 0.69 (1.726"/2.5").
I would multiply the actual thickness for the 23" x 6’10" (82") surfboard (3.25") by the same ratio of mean to actual thickness (0.69 x 3.25"). Guesstimated mean thickness would be 2.24".
Voume for a 2.24" thick, 23" x 82" elliptical shape would be 2.24" x 11.5" x 41" x pi (3.1416) = 3318 in^3 = 54.4 L.
Using this approach, the approximate volume for a 3.25" x 23" x 82" SB would be 54.4L.
If I needed a quick volume estimate, this is how I would do it.
However, I don’t see much advantage in comparing the same volume value among different shapes – relative to performance.
That IS the best explanation and calculation on getting to volumne via a formula. A little over this old mans head, but definitely the best explanation. Thanks Stoney. Lowel
If you post an impage of your tempate and dimensions that would make it easy to provide volumes.
In my opinion, you only need enough volume to float and support you while you paddle. After that its surface area and rocker. A 13" diameter log might float you but it would’t paddle very well, let alone surf well.
The board is glassed and finished, all hand shaped from an 80’s template but given a modern rail design. - should be fine with the extra volume. The fun part is testing it out
Forgive me for not understanding, but if this is a finished board and you are not in the planning or design stage then what difference does it make what the volume is? You’re going to surf what you got, right?
There is no way you can calculate surfboard volume with a suffisant accurancy to make this numbers usable.
Only way here is water tank.
Volume in surfboard industry is more ore less a joke because boards are more or less far from original software model cut file. i often repair “big name” surfboards even simple dims like lenght or thickness are 1 to 5% wrong from what is write on blank so volume…
