Page 1 of 3
Underwater Air Supply
Posted: Wed Aug 23, 2006 9:39 pm
by Atlantis
I'm trying to find a way to get an air supply underwater without using air tanks, basically I need a way to be able to run an air hose up the surface.
The problem is that my SCUBA Diving friends said there would be a pressure problem. I only plan on 20 ft max. I assume the pressure would cause my lungs to explode, I need an wasy way to regulate the pressure.
Any ideas?
Posted: Wed Aug 23, 2006 10:09 pm
by huse_spud
what's ur air supply? a compressor will be worse than smoking a mary-J cigar.
it sounds like a stupid ideer but explain more please...
Re: Underwater Air Supply
Posted: Wed Aug 23, 2006 10:45 pm
by Atlantis
Atlantis wrote: basically I need a way to be able to run an air hose up the surface.
I need to run a hose to the surface for air, like a really long snorkel tube, but apparently theres an issue with pressure. Is the pressure even wrth worrying about at 10-20 ft?
Posted: Wed Aug 23, 2006 10:49 pm
by SpudStuff
just get an extender hose at the local dive shop. I use them all the time
Posted: Wed Aug 23, 2006 10:54 pm
by Atlantis
So I don't need to use some kind of regulator? If so, that's good. I might just add a water hose to a snorkel and attach the end of the hose to my friends paddle boat. Now I just need to find something to way me down. Any idea how deep I could go without pressure issues?
Posted: Wed Aug 23, 2006 11:00 pm
by saladtossser
shouldnt the pressure in your lungs equal the water pressure at depth?
Posted: Wed Aug 23, 2006 11:01 pm
by Atlantis
Well the air from the surface would be lower than the pressure down there, less pressure inside your lungs than outside.
Posted: Wed Aug 23, 2006 11:02 pm
by sergeantspud2
Wait hold on... your trying to take a garden hose and basically use it as a long snorkel?
EDIT:oh nevermind I was thinking of something that didn't make sense.
sorry.
Posted: Wed Aug 23, 2006 11:08 pm
by Atlantis
I'm gonna test this off my friend's boat. I'll slowly decend, so I know when to stop if I need to.
Posted: Wed Aug 23, 2006 11:11 pm
by sgort87
Actually, what happens when you get lower is that it becomes extremely hard to breathe in that air from the surface through a tube. Many many years ago I had the same idea to take a hose and hook it up with one way valves on a snorkel and just float around under water. Unfortunately, about only 3 feet under water it became almost impossible to breathe anything.
What you need to do is set up a pressurized hose to feed you air when you need it. You can have it run through a couple one way valves at a pressure equal to the pressure of the water and that will allow you to breathe normally.
It goes from a tank to a hose to a one way valve to your mask/snorkel to another one way valve for exhaust.
Posted: Wed Aug 23, 2006 11:29 pm
by boilingleadbath
You ever tried sucking 10 psi?
It's not possible; you'll need forced air.
Breathing from a blowgun ain't safe; you'll pop a lung.
Breathing from the "upright" section of a T with the air input through the top would be possible.
Keep the flow restrictor on the blowgun, or even make a smaller one - last thing you need is more flow.
Ways to keep yourself down?
A belt of (lead) weigts with a quick release. It's what the professionals use.
What's that, you say? "What if I put too much weight on?"
Well, real divers have something called a "boyancy control device" - which typicaly takes the form of a vest with an inflatable pocket. They have low-pressure checkvalve type inflators, for mouth usage - but that SUCKS to use (really), so you'll want to make it so you can use your air hose to inflate it.
About your nitrogen issues - so long as you stay down for less than 3 hours, at 20', once per day (I'm not going to acctualy check my dive tables), you'll be a safe little bugger.
Which won't be an issue, considering how fast you'll get cold in 60*F water. F, I get cold in 65*F water with a 6mm wetsuit on.
Ya got fins? 'Cause if you don't, ya gonna be one immobile idiot.
Oh, and a quick list of suggestions for diving:
1) DON'T hold your breath. Ya wanna die?!
2) Go with a buddy.
3) If ya lose your hose, or run out of air, scream like the scared M*th*rF*ck*er you are and release your weight belt. With any luck you won't pop your lungs on the way up (and keep screaming. It's the only thing preventing a potentialy fatal lung injury.) Don't worry about running out of air - the air in your lungs will expand on the way up.
4) If ya get a cramp, swear like a sailor, stretch the mussle, and massage until ya regain functionality.
Oh... yeah, wear a full-face mask (covers nose), and don't forget to equalize your ears and sinuses on the way down.
Such is done by holding your nose and trying to exhale. Squeeking noise will result.
If you get water in your mask, look upwards, and peel your mask upwards (so it only touches at the top). Proceed to emmit bubbles from your air supply while shaking your head side to side.
90% of eardrums pop by 14 psi pressure difference, IIRC. And even a couple psi hurts.
(I appologize for any vulgar language. I'm having a bad day, and can't be bothered to be polite with suicidal idiots.)
Posted: Wed Aug 23, 2006 11:55 pm
by Atlantis
I don't really plan on per say "dive", I just want to walk around on the bottom for a minute or 2, which is about 10-20 feet down. I don't plan on any long stays, the waters too murky to see much anyways down there, I just want to see if it can be done. Me and my friend might build a really simple sub, one that won't be able to go completely underwater, just under maybe, enough to qualify as a sub.
P.S. I'm not suicidal, if I was suicidal I would just do it without asking for advice.
P.S.S Could somebody draw me a picture of what system I would need for this kind of operation.
Posted: Thu Aug 24, 2006 12:47 am
by boilingleadbath
Oh... in that case...
Put a life jacket on, attatch an overly heavy weight belt. Lower yourself, and raise yourself, by climbing a rope with a brick tied to it, connected at the top to the boat.
It'll take about 1 minute to just go down then up safely, but I get your drift.
looks something like this:
(air in)
n
||
| =:o (you)
||
||
||
(open bottom)
Posted: Thu Aug 24, 2006 10:59 am
by Kris.Is.Awesome
I'm a PADI diver myself.. the reason you can breathe at depth with a scuba tank, is that its an on-demand force-fed supply. I don't think you can go under even 20 ft and suck air. I wouldn't try it. I made a snorkel and at 5 ft it was almost straining... Remember the rule 11... 33... etc.
Posted: Thu Aug 24, 2006 11:49 am
by WOW!!
You said you have a friiend(s) that dive? Then why dont you just use the same set up as a SCUBA system, but take a hose and put it from the tank to the boat with the tanks on it? That might work.