Lift and Tuck!! bouyancy compensators.

**moley** · 21st March 2006, 06:55

Hi Folks,

I am somewhat puzzled. (and lets face it,in my case that aint difficult).

During my Padi Bubblemaker course, and those that followed, something has eluded me in the technickle department. (along with most of the rest of it
I guess)

I understand that to rig a lightweight cressi travel bcd in size small with a meg and a couple of stages in full UK kit could be as much of a no-no as a halcyon 55lb wing with a single 12 ltr ally cylinder and me skimpy lycra pants (Nice!!

)

I dont grasp what the correlation between this term 'lift' and the '55/40lb' that usually follows:

Is it as simple as saying that a 40lb wing will lift 40lbs up from the bottom....there has to be more to it than that surely?

***schford*** · 21st March 2006, 07:44

It is saying it displaces the equivalant amount of water to that weight so ergo provides that much positive bouynacy.

Metric is so much easier as if something has lets say 10kg of lift you know it displaces 10l of water (roughly ignoring salt etc etc)

The main reason why people want a lot of lift is to be able to bring up your buddy form the bottom - or hold them up at the surface or to ensure your head stays well clear of the water when using a filly inflated wing.

Archimedes Law tell us...

The upward force (buoyancy force) is exerted on a body floating in a fluid. It equals the weight of the displaced fluid.

Stuart

**nigelh** · 21st March 2006, 08:10

Quote: (Originally Posted by moley)

I dont grasp what the correlation between this term 'lift' and the '55/40lb' that usually follows:
Is it as simple as saying that a 40lb wing will lift 40lbs up from the bottom....there has to be more to it than that surely?

My take on weight and lift.

**woody** · 21st March 2006, 11:33

Quote: (Originally Posted by nigelh)

My take on weight and lift.

Nigel,

That website is superb!

Mike

**moley** · 21st March 2006, 11:44

Nigel/ Stuart

Thanks for that.......gotta be fair Nigel, that web site of yours is superb...tearjerkingly funny and written in non technospeak!!

21st March 2006, 06:55	#1 (permalink)
moley Supporting Member Current Rebreather/s: Megalodon Sport Kiss Other Rebreather/s: Megalodon Sport Kiss Join Date: Nov 2005 Location: wiltshire, Uk Posts: 124	Lift and Tuck!! bouyancy compensators. Hi Folks, I am somewhat puzzled. (and lets face it,in my case that aint difficult). During my Padi Bubblemaker course, and those that followed, something has eluded me in the technickle department. (along with most of the rest of it I guess) I understand that to rig a lightweight cressi travel bcd in size small with a meg and a couple of stages in full UK kit could be as much of a no-no as a halcyon 55lb wing with a single 12 ltr ally cylinder and me skimpy lycra pants (Nice!! ) I dont grasp what the correlation between this term 'lift' and the '55/40lb' that usually follows: Is it as simple as saying that a 40lb wing will lift 40lbs up from the bottom....there has to be more to it than that surely? __________________ *You think I know nothing.....and I do!!!*
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21st March 2006, 07:44	#2 (permalink)
*schford* Despotic Overlord Current Rebreather/s: Megalodon Sport Kiss Other Rebreather/s: Join Date: Jan 2005 Location: London, UK Posts: 3,660	Re: Lift and Tuck!! bouyancy compensators. It is saying it displaces the equivalant amount of water to that weight so ergo provides that much positive bouynacy. Metric is so much easier as if something has lets say 10kg of lift you know it displaces 10l of water (roughly ignoring salt etc etc) The main reason why people want a lot of lift is to be able to bring up your buddy form the bottom - or hold them up at the surface or to ensure your head stays well clear of the water when using a filly inflated wing. Archimedes Law tell us... The upward force (buoyancy force) is exerted on a body floating in a fluid. It equals the weight of the displaced fluid. Stuart __________________ Bailout and Kit Management account for Murphy's Law The only bad question is one you did not ask and later wish you had. Use of Rebreather World is subject to the Rebreather World Terms & Conditions of Use
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21st March 2006, 08:10	#3 (permalink)
nigelh New Member Current Rebreather/s: Inspiration Vision Other CCR Other Rebreather/s: Inspiration Classic Other CCR Join Date: Mar 2005 Location: Brighton, Sussex, UK Posts: 784	Re: Lift and Tuck!! bouyancy compensators. Quote: (Originally Posted by moley) I dont grasp what the correlation between this term 'lift' and the '55/40lb' that usually follows: Is it as simple as saying that a 40lb wing will lift 40lbs up from the bottom....there has to be more to it than that surely? My take on weight and lift. __________________ nigelh
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21st March 2006, 11:33	#4 (permalink)
woody Mmmm Rubber!! Current Rebreather/s: Megalodon Other Rebreather/s: Inspiration Classic Inspiration Vision Evolution Sport Kiss Join Date: May 2005 Location: Wiltshire UK Posts: 190	Re: Lift and Tuck!! bouyancy compensators. Quote: (Originally Posted by nigelh) My take on weight and lift. Nigel, That website is superb! Mike __________________ Not eloquent enough for a smart arse signature!
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21st March 2006, 11:44	#5 (permalink)
moley Supporting Member Current Rebreather/s: Megalodon Sport Kiss Other Rebreather/s: Megalodon Sport Kiss Join Date: Nov 2005 Location: wiltshire, Uk Posts: 124	Re: Lift and Tuck!! bouyancy compensators. Nigel/ Stuart Thanks for that.......gotta be fair Nigel, that web site of yours is superb...tearjerkingly funny and written in non technospeak!! __________________ *You think I know nothing.....and I do!!!*
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