How Much (back up/emergency lift in a Safety Sausage?

[jim T.]

Does anyone know how much back up or emergency lift would be available in a 6' (x3")
safety sausage? I'll go experiment if no one knows, but it may be a few days. I figure there wouldn't be much but I don't know the physics/formula of the matter

It's mostly a rhetorical question but hey, it could be nice to know.
Haven't gotten a lift bag yet, but soon will.
Thanks

 

[micklock]

I just bought one from leisurepro, the 5' 2" oms and it is 55 lb lift.

 

[don Francisco]

Rough math as follows,
Volume of a cylinder = pi x radius squared x length.
Keeping it in feet the 3" diameter = 1/8' radius, so we have approx 3x(1/8x1/8)x6 = 18/64cuft.
@64#/cuft water density or fairly close to 18# if fully inflated.
Pi is slightly more than 3 & salt water is slightly denser, so you might have 19#s.

A problem is that if fully inflated at depth it might burst as you rise unless vented.
Hopefully you'll never need this.

 

[Buoyant1]

I'm not going all "math major" on ya, but I think I just read somethign that the average safety sausage was good for about 60 lbs of lift (give or take)

 

[jim T.]

Wow. Don F., For a professional bicycle guy, you sure know some math! Must be more physics in bikes than I thought. Thanks!
That's more than I thought it'd be (I was thinking maybe it'd be 10 lbs.)...
Hopefully I never will, and not likely with the double bladder wing, (wetsuit diving) and
drysuit but thought it would be prudent to at least know 'cause...well...ya just never know!
Thank You.

micklock. Wow, 55lbs? That doesn't seem possible. A 55lb. lift wing is a heck of a lot bigger than that. Is that what L.P. states?
Eventually I try lifting a weight belt just for fun and because I grew up with Mr. Wizard's TV show and must experiment

 

[don Francisco]

Jim- for a quick rough estimate, inflate the sausage & compare it to the quart of mike in the fridge. Crosssection is about the same, length about 8-10 quarts. weigh the milk, about 2#s or so. per quart. Total displacement = 16-20#s
It doesn't matter what the average sausage displaces, yours is good for 18-20#s.
fb

 

[cool_hardware52]

Wow. Don F., For a bicycle guy, you sure know some math! Thanks!
That's more than I thought it'd be (I was thinking maybe it'd be 10 lbs.)...
Hopefully I never will, and not likely with the double bladder wing, (wetsuit diving) and
drysuit but thought it would be prudent to at least know 'cause...well...ya just never know!
Thank You.

micklock. Wow, 55;bs? That doesn't seem possible. A 55lb. lift wing is a heck of a lot bigger than that. Is that what L.P. states?

If you really want to know weigh the smb empty, and then fill full of water and weigh it again. The difference in the two values will equal the buoyancy it can provide fully inflated. This works for wings also.

I'll bet the "back of the napkin" calc's posted already are pretty close, if the dimensions are accurate.

Tobin

 

[micklock]

OMS 5' 2" Long Surface Marker Buoy with 55 lb. Lift from LeisurePro.com Thats what it said, but I don't' know for sure.

 

[nannymouse]

18.814809 lbs displacement at surface level.

A 60 lb lift bag would be about 1 cubic foot.

Iif it was fullu inflated it would not displace any more at depth than at surface, so wouldn't the lift be the same?

 

[jim T.]

Doh. I didn't think of that Tobin! Makes perfect sense.
Micklock, yep, that's what it says alright. Hmmm... let me know if you ever check it out via
experiment?