Lift Capacity Question: HOG 4.5ft SMB
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CT Sean
Contributor
Certainly can't speak for all SMB's but my DAN 6"x72" is 6 inches wide FLAT (the inflatable portion anyway - it's about 7" wide overall), not 6 inches in diameter.
Just for fun: 6" wide flat gives a 3.8" diameter
1.9^2 * 3.142 * 72 = 816.67 cu in
816.67 / 1728 * 64 = 30.25 lb buoyancy
Doing the same for a 7 x 48 (assuming the 7" is a flat measurement as well)
7 * 2 / 3.142 (to get diameter) = 4.5
2.25^2 * 3.142 * 48 = 763.51 cu in
763.51 / 1728 * 64 = 28.28 lb buoyancy
Just for fun: 6" wide flat gives a 3.8" diameter
1.9^2 * 3.142 * 72 = 816.67 cu in
816.67 / 1728 * 64 = 30.25 lb buoyancy
Doing the same for a 7 x 48 (assuming the 7" is a flat measurement as well)
7 * 2 / 3.142 (to get diameter) = 4.5
2.25^2 * 3.142 * 48 = 763.51 cu in
763.51 / 1728 * 64 = 28.28 lb buoyancy
CT Sean
Contributor
deleted - double post
OP
How did you get the 3.6" diameter from the 6" flat measurement?
I think that may be the problem with our calculations.
I think that may be the problem with our calculations.
CT Sean
Contributor
The "flat" measurement is half the circumference right?
So the total circumference that can be made from a 6" wide flat thing is 12". From there I just backed into the radius (circumference divided by pi = diameter / 2 = radius) then I inflated and measured SMB to make sure
So the total circumference that can be made from a 6" wide flat thing is 12". From there I just backed into the radius (circumference divided by pi = diameter / 2 = radius) then I inflated and measured SMB to make sure
The "flat" measurement is half the circumference right?
So the total circumference that can be made from a 6" wide flat thing is 12". From there I just backed into the radius (circumference divided by pi = diameter / 2 = radius) then I inflated and measured SMB to make sure
Good point about the flat measurement!
OP
O_O
That makes so much sense now
....I believe you have solved it.
Thanks
That makes so much sense now
....I believe you have solved it.
Thanks
OP
Well, now if only someone could tell me the dimensions of the HOG SMB.....9~9
Jorgy
Contributor
So why would a smaller (less lift) DSMB be easier to deploy at depth?
I think any DSMB would only be as buoyant as the amount of air you get in it before you release it.....so any large lift bag could be "just" 25 lbs of lift.....
A longer "thinner" DSMB might be harder to get air into "quickly" before it gets to buoyant and you need to release it......
I use a Carter 35 lb Personal Float with an open bottom which is very easy to fill (4" diameter), I put a small burp of air in it to extend the bag vertically and then a big exhale to shoot it to the surface....seems to work well for me......I never even take the reg out of my mouth......
Personal Floats Safety Sausage Tubes
My apologies if I didn't follow the thread correctly......
Just my thoughts.......M
I think any DSMB would only be as buoyant as the amount of air you get in it before you release it.....so any large lift bag could be "just" 25 lbs of lift.....
A longer "thinner" DSMB might be harder to get air into "quickly" before it gets to buoyant and you need to release it......
I use a Carter 35 lb Personal Float with an open bottom which is very easy to fill (4" diameter), I put a small burp of air in it to extend the bag vertically and then a big exhale to shoot it to the surface....seems to work well for me......I never even take the reg out of my mouth......
Personal Floats Safety Sausage Tubes
My apologies if I didn't follow the thread correctly......
Just my thoughts.......M
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