Sea Rider
Supreme Mariner
- Joined
- Sep 20, 2008
- Messages
- 12,345
Re: A question for any scientists out there
Long time wanting to know with apropriate tools how much pressure a sib loses or gains once on water : Inflated a 380 sib to 3.0 psi on all chambers at 10 AM on a foggy day.
Exterior temperature 22? C - 71.6? F
Water temperature 15? C - 59? F
Sib Pressure 3.00 PSI
30 Minutes Later on water :
External temperature 22? C - 71.6? F
Water temperature 15? C - 59? F
Sib pressure 2.80 PSI
Tube temperature 23? C - 73.4? F
Checked conditions at 2.0 PM, the day was clear and slight sunny
External temperature 25? C - 77? F
Water temperature 16? C - 60.8? F
Sib pressure 3.0 PSI
Tube temperature 26? C - 78.8? F
Some conclusions in my particular case & location :
-With such small amount of pressure lose, you could not tell by finger/feel test the pressure difference at all.
-The colder the day and water, will lose more pressure.
-The warmer the day with near same water temp, gains more pressure.
-In plain summmer with about same water temp and 28? outside temp, usually inflate sibs to just 2.5 PSI, let sun do the overinflation to 3.0 PSI
-In plain winter with water temps of 12?-14? and no sun inflate sib to 3.25/3.5 to have near 3.00 PSI after deflation.
-Any sib/rib inflated to 3.5 PSI will be too bumpy if light loaded, recommended if fully loaded to have boat rigidity and top performance.
-The pressure that gives rigidity to any inflatable will vary accordinglly in coastal uses to : PSI inflated to, external temp & water temp.
TG states pressure loses of 0.5 to 1.0 PSI, that sib must have a fabric leak product of fishing
, he doesn't use a gauge, has a feel gauge finger product of experimenting pressures to touch or bending rear cones, this method won't give same pressure on all tubes as using a real gauge for overall all chambers rigidity. It's like inflating your car tires at touch.
Happy Boating
Long time wanting to know with apropriate tools how much pressure a sib loses or gains once on water : Inflated a 380 sib to 3.0 psi on all chambers at 10 AM on a foggy day.
Exterior temperature 22? C - 71.6? F
Water temperature 15? C - 59? F
Sib Pressure 3.00 PSI
30 Minutes Later on water :
External temperature 22? C - 71.6? F
Water temperature 15? C - 59? F
Sib pressure 2.80 PSI
Tube temperature 23? C - 73.4? F
Checked conditions at 2.0 PM, the day was clear and slight sunny
External temperature 25? C - 77? F
Water temperature 16? C - 60.8? F
Sib pressure 3.0 PSI
Tube temperature 26? C - 78.8? F
Some conclusions in my particular case & location :
-With such small amount of pressure lose, you could not tell by finger/feel test the pressure difference at all.
-The colder the day and water, will lose more pressure.
-The warmer the day with near same water temp, gains more pressure.
-In plain summmer with about same water temp and 28? outside temp, usually inflate sibs to just 2.5 PSI, let sun do the overinflation to 3.0 PSI
-In plain winter with water temps of 12?-14? and no sun inflate sib to 3.25/3.5 to have near 3.00 PSI after deflation.
-Any sib/rib inflated to 3.5 PSI will be too bumpy if light loaded, recommended if fully loaded to have boat rigidity and top performance.
-The pressure that gives rigidity to any inflatable will vary accordinglly in coastal uses to : PSI inflated to, external temp & water temp.
TG states pressure loses of 0.5 to 1.0 PSI, that sib must have a fabric leak product of fishing
Happy Boating