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board volume

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Created by wham70 > 9 months ago, 20 Apr 2010
wham70
NSW, 44 posts
20 Apr 2010 8:27PM
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Hi guys is there any way to calculate the volume of a board if it isnt written on it

Windxtasy
WA, 4019 posts
20 Apr 2010 6:31PM
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Could try the Archimides principle if you have a large enough bathtub...

Gestalt
QLD, 14969 posts
20 Apr 2010 9:16PM
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put the board in a pool and load it up with weights until it sits flush with the top of the water.

weight = volume

Mobydisc
NSW, 9029 posts
20 Apr 2010 10:15PM
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Gestalt said...

put the board in a pool and load it up with weights until it sits flush with the top of the water.

weight = volume


Is that always true? Dunno coz its been years since I've done any physics or maths like that. What I'm thinking is some materials are more buoyant than others and have different densities. I could be completely wrong about this.

I would have thought Windxtasy's thought of Archimides principle would be the go.

Anyway what sort of board is it? There could be someone here that knows the board and its stats.



wham70
NSW, 44 posts
20 Apr 2010 10:28PM
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It's a hardcore freeride/wave 260-60-110thick fiberglass there are numbers on the stringer but none are volume they are 260x600x400x310x110 . I don't know what the outher measurements are for?

garyk
QLD, 277 posts
20 Apr 2010 10:29PM
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An object displaces the water volume of its weight
1000ml = 1000g = 1000cm cube

Gestalt
QLD, 14969 posts
20 Apr 2010 10:31PM
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yes it's true, and it is how board volume is checked within the industry.

Mobydisc said...

Gestalt said...

put the board in a pool and load it up with weights until it sits flush with the top of the water.

weight = volume


Is that always true? Dunno coz its been years since I've done any physics or maths like that. What I'm thinking is some materials are more buoyant than others and have different densities. I could be completely wrong about this.

I would have thought Windxtasy's thought of Archimides principle would be the go.

Anyway what sort of board is it? There could be someone here that knows the board and its stats.






decrepit
WA, 12888 posts
20 Apr 2010 8:37PM
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Mobydisc said...

<<<<

Is that always true? Dunno coz its been years since I've done any physics or maths like that. What I'm thinking is some materials are more buoyant than others and have different densities. >>>>>>>>




Yep, doesn't matter what the density or buoyancy is, if it's just completlly submerged, but still floating, it's weight is the same as the volume of liquid it's displacing.
If that's pure water, it's 1kg per litre.
Sea water is a bit heavier, it's been stated here before on similar threads, by exactly how much, but ancient sieve for brains memory forgets.

So you have to weigh everything that's sinking the board, including the board's own weight, to get it's volume.

garyk
QLD, 277 posts
20 Apr 2010 10:49PM
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So if a board weighs 6kg it will only displace 6L of fresh water under it.
put 70kg on the board and it will displace 76L of fresh water and if its a 76L board this is where it starts to sink. For anything to float all it needs to be is less dence than water in my case im more dence so I sink A sinker will sink but flaten it out and add sides and it will float. material dosent change the laws of displacement its the volume and weight.

sailpilot
QLD, 787 posts
20 Apr 2010 10:52PM
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Seawater is taken to be 1.025 kg / L, in actual fact this too varies with water temp and is correct in water of 4degC, (ie I'll never sail in that density)
So a 100 L board in seawater will float the same as a 102.5 L board in fresh water.

evlPanda
NSW, 9207 posts
20 Apr 2010 10:58PM
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Don't forget that red boards are louder than, say, blue boards and therefore have more volume.

decrepit
WA, 12888 posts
20 Apr 2010 9:12PM
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Oh yeah and don't forget, if your weights go under water, you're also measuring the submerged part of their volume.

nosinkanow
NSW, 441 posts
21 Apr 2010 1:44AM
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wham70 said...

It's a hardcore freeride/wave 260-60-110thick fiberglass there are numbers on the stringer but none are volume they are 260x600x400x310x110 . I don't know what the outher measurements are for?


This is like a guessing competition.

260cm = length
600mm/60cm = widest point
400mm/40cm = 1' from tail
310mm/31cm = 1' from nose
110mm = thickness

Volume =Big guesstimate 75 litres.

Sit on it in a pool, see how much it sinks. If it hardly sinks its volume is greater than your weight in litres, if it sinks it's the opposite, if it sinks just below the surface it's the same volume as your weight....errr follow that? It's still another guestimate but close me thinks.

wham70
NSW, 44 posts
21 Apr 2010 8:22PM
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Cheers thanks for everyones input .

kato
VIC, 3532 posts
21 Apr 2010 9:01PM
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Try this peterman.dk/windsurf-boardvolume780-gb.htm



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"board volume" started by wham70