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It is true that you will pay $3500 on up for a scuba compressor that pumps safe air. But a proper low pressure compressor system using the right hose, regulator or mask and filtration will cost as much as $1000 ... even in the PI!

Lots of things have been brought up here and some of them are gold and some pure BS.

So, lets start with air source.
  • A scuba tank with a long hose is great since it is filled with filtered grade E air. The drawback is that most second stage regulators (the part that goes in your mouth) and breathe harder the deeper you go. Additionally, you have no indication of how much air is left in the tank until you run low and it gets REALLY hard to draw a breath.
  • Next is a compressor. You can use just about any compressor that can put out the proper flow rate. Remember, when you are underwater pulling a wrench or scrubbing the bottom, you are breathing harder than if you are just sitting on the deck. Plus, even though it is pretty shallow at the keel, the increased density of the air means higher flow rate. Commercial compressors for 20' or less are 12 CFM or bigger so go with something that size.
Next is filtration.
  • The act of compressing air increased the density. But, since water is not compressible, the humidity level is greatly increased. Plus, there is always a little carryover from whatever lubrication is used in the compressor. so, a proper moisture separator will remove a bunch of the moisture and then you follow with a chemical filter bed. Additionally, any compressor will impart an odor/taste into the air so you will need a charcoal filter as well to sweeten the air. And ... NO ... those cheap plastic air filters just don't cut it.
Air storage
  • It is important to have a backup air source should your compressor shut down. Most LP compressors are available with a holding tank. If you are pumping away and working at depth and run out of gas, propane, electricity or squirrel food, the compressor stops. Believe or not, you can generally hear a compressor running through the air hose and, if the sound stops, the volume tank gives you enough to safely make your ascent.
The regulator
  • Standard SCUBA regulators are built to operate at from between 120 and 175 PSI and are pretty finicky. If the feed pressure drops a a couple of pounds, it becomes a little harder to breath. For a low pressure compressor, there are special compressors meant to operate at lower pressures and are a little more difficult to find.
  • The feed hose to the regulator needs to be made of the proper material. Cheap rubber hose breaks down rapidly and tastes terrible! Cheaper vinyl hose tastes terrible all the time! Get proper breathing air hose. It ain't cheap but makes working under the keep a LOT more comfortable.
OK ... all that said ... forget the DIY hooka system. You bought a boat to travel and enjoy yourself. Learn scuba, bring your gear aboard and dive in cool locations.
 

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For the most part, Ray gives good advice above. I would take exception with three points, primarily because I feel he didn't give them enough emphasis:

1.- In a DIY system you should use an oil-less compressor only.

2.- Depending on how you plan to use your hookah, air storage and the associated plumbing are not necessary. For hull cleaning, I would say there is no need.

3.- This cannot be stressed enough; only mil-spec breathing hose should be used. It's not a matter of how the air tastes or the hose degrading or whatever. It's a matter of breathing poison or not.
 

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Otter
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I use a ROL-AIR compressor with my company on basic jobs and a Quincy diesel for deep dives. If you are not using an oilless compressor you MUST USE MONOLEC! Monolec is one of the only approved oils for compressors PERIOD! I would steer clear on making your own unless you really know dive physics and dive medicine. We buy the bare compressors but plumb the fittings and in line filters ourselves when we are not using HP Bottle Banks. That being said DO NOT use cheap pvc hose. Get yourself a legitmate breathing hose approved for diving. Also , that compressor needs to be pumping out enough CFM and PSI to get the air down to you. Its not as simple as throwing a reg in your mouth and going for it, there is ALOT of math going into diving that needs to be considered. If you really want a compressor I reccomend buying a premade off the shelf model. If you are going shallow like under a hull just get a hookah off the bottle set up, but DONT try to make your own. The only reason we do it is we are trained and experienced. Its not something you want to skimp out on or try to save money.
 

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Great response Ray, thanks. Below that are additions by two professionals who work in the field and literally live or die by this technology. Gotta love SailNet. :D

I would only add the emphasis again that SCUBA certification is necessary AND worthwhile. It's cheap (usually under $150) and they teach you the stuff you didn't even know you didn't know that WILL kill you if you didn't learn it.

Additionally, getting a small pony tank + reg could be one option for additional safety instead of the stored air in the compressor tank. More redundant, but much more expensive and filling the tank is an issue as you need a SCUBA compressor. There is also a self contained unit called Spare Air that you could take down with you also, but again at increased cost and difficulty filling.



I do think the DIY can be done safely if you really do your homework, but as has been mentioned before, a purpose-built hooka system off E-bay is probably the safest/cheapest/best option proposed so far IMHO.

MedSailor
 

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I do think the DIY can be done safely if you really do your homework, but as has been mentioned before, a purpose-built hooka system off E-bay is probably the safest/cheapest/best option proposed so far IMHO.
As I've mentioned before, the purpose-built hookahs sold on e-Bay are, for the most part, based on cheap, Chinese compressors that anybody can buy at Home Depot for a couple hundred bucks. The sellers are simply guys in their garages putting together the absolute most low-budget hookahs they can, and then marketing them on e-Bay as high end surface-supplied air rigs. They are junk and will not survive long in a marine environment.

In reality there are only a couple really reputable recreational-level hookah sellers in this country and they are Airline by J. Sink and Brownie's.

Air Line Diving System | The Air Line by J. Sink
Brownie's Third Lung Diving, Hookah Surface Supplied Air Systems |
 

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I have nothing against belt and suspenders, so one can carry Spare Air, if they must.

However, if you can not do a no air ascent from 6 feet, you should not be cleaning your hull on compressed air.
 

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As I've mentioned before, the purpose-built hookahs sold on e-Bay are, for the most part, based on cheap, Chinese compressors that anybody can buy at Home Depot for a couple hundred bucks. The sellers are simply guys in their garages putting together the absolute most low-budget hookahs they can, and then marketing them on e-Bay as high end surface-supplied air rigs. They are junk and will not survive long in a marine environment.

In reality there are only a couple really reputable recreational-level hookah sellers in this country and they are Airline by J. Sink and Brownie's.

Air Line Diving System | The Air Line by J. Sink
Brownie's Third Lung Diving, Hookah Surface Supplied Air Systems |
Thanks for clarifying this for me! I did not know that there were garage-built "dive compressors" for sale on ebay,:eek: though I should not be surprised. When I recommended buying a compressor off ebay, I meant a used brownies third lung or other commercially manufactured unit.

MedSailor
 

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I'd suggest that SpareAir, in this context, is just one of the many ways dive shops are using FUD to sell more gear and make more profit. There is absolutely no need for "reserve" air if you are working on a recreational sailboat, where you will simply never be more than ten feet below the surface.

If someone can't hold their head together and make a free ascent from ten feet, even on empty lungs, THEY SHOULDN'T BE THERE IN THE FIRST PLACE. Period.

All the extra gear in the world won't help someone who simply should not be there. The trend in the diving industry today is to insist that divers need computers, spare air, and K valves because J (reserve) valves are too dangerous. Bullpuckey! I'd rather have one cam and one spring (the J valve) and know that it is my job to ensure it has not fouled or tripped, than to rely on an extra five pounds of gear, more valving, a second regulator, and a batch of electronics and o-rings and batteries.

Most dive shops can only survive if they can figure out a clever way to get money on a regular basis, more and more every year. Most, not all. Very few dive shops or locations have been around for 30-40 years, they seem to typically last maybe ten years and then dry up and blow away. To stick around, they need a hook (contract with a local college or municipal first responders or a boat and resort location etc.) and even then, everyone is trying to sell more, often at obscene prices.

Like the push to do VIP+ instead of a VIP, all the time, when VIP+ is simply needless on new tanks or steel tanks. "Oh, we do it all the time" shouldn't be my problem, it isn't appropriate and it wastes my money.

Then there are the shops that all "require" a current VIP after a hydro. Require? The DOT requires a visual inspection before the hydro test, and that tester has been trained and certified to do it. So why should an unregulated dive shop require a redundant VIP by some dive association franschisee on top of that? Oh, well, so they can make $15 for a five minute looksee.

Sorry, guys, but while I readily agree with what I was taught, that diving can easily kill you, I also think the whole recreational/sport diving industry is based on FUD not safety. I've had too much crud turn up in tanks that were only filled by certified shops, and heard too much BS from the operators.

And I most firmly think NASDS was right and every other organization was wrong: You've GOT to do panic screening and you've GOT to fail some students, if they just don't have the presence of mind to be safe divers.

DIY hookah? Hell, Jacques Costeau used DIY equipment when he started. Maybe he was lucky as well as skilled. But diving on a sailboat, which is no deeper than diving in most pools, isn't quite the same as maintaining oil drilling equipment in the North Sea.

If the air is of a safe breathing quality, all the rest is details. Except the suitability of the diver.
 

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I'd suggest that SpareAir, in this context, is just one of the many ways dive shops are using FUD to sell more gear and make more profit. There is absolutely no need for "reserve" air if you are working on a recreational sailboat, where you will simply never be more than ten feet below the surface.

If someone can't hold their head together and make a free ascent from ten feet, even on empty lungs, THEY SHOULDN'T BE THERE IN THE FIRST PLACE. Period.
Agree with this part, but some of the Brownies third lung systems are rated to a depth of 90ft. Personally I'd like some kind of redundancy at that depth. J-valve to pony, pony with reg, or spareair or a straw to suck the air out of your drysuit ;). No need for a backup if the system is for changing zincs.

Of course, one DIY system that won't contaminate your lungs is the $10 system developed and used by Motessier. On page 167 of his book "sailing to the reefs" he details a system of upturned buckets, weights, lines and other bits. He was able to use this system (with his friend refilling the buckets of air, upturning them and sending them down to him with a weighted line. Simplicity itself. ;)

Check it out free here on google books:
Sailing to the Reefs - Bernard Moitessier, Rene Hague - Google Books

MedSailor
 

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He seems to have re-invented the 4th century BC diving bell as described by Aristotle and others,
and added some complications and a hose so that a small bell not enclosing the diver could be used. 2500 years of progress.
 

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Otter
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Dont forget if you ran out of air at 6 feet and held your breath on the way up in a panic you will most likely be in a serious world of hurt. If you dont know what im talking about look up Boyles law and Pulmonary Overinflation.
 

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True, but if you can't do a free ascent from 6 feet, you should not be using diving equipment either. Or 10 feet or 20 feet or even 30 feet in my view. That's just me though.
 

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Not related to last post, just a thought:
When you free ascend you take in air at sea level so it would be impossible to cause issues like you would see with tank or hookah diving. I think that is the biggest risk with hookah diving without a diving cert, you really need to understand the problems that can occur if you hold your breath on ascent. My dive instructor did the classic example of a balloon filled at depth then released to the surface. It got the point across well.
 

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I have a Brownies. Dumped the float and base, put it in the dinghy, much less stuff to store and carry around. Friends use a $130 generator ,hooked up to a $149 oil less compressor for hull cleaning. Works well. Raise the air intake as high as possible on an extension tube. A snorkel with a purge valve works as well as a regulator. Old Johnson Air buoys used that principle.
 

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When you free ascend you take in air at sea level so it would be impossible to cause issues like you would see with tank or hookah diving.
I'm not being picky, but this statement is technically wrong and dangerous. A free ascent is defined as: "An emergency procedure used to return to the surface. The diver swims or floats to the surface while breathing all the way up." If you hold your breath at any time during a free ascent you are placing yourself in harms way. The balloon example is a good one and if nothing else highlights why no one should use compressed air diving equipment without proper instruction in it's use. Which I think was the point of this post, but unfortunately the wrong term was used.

Free diving is when you take your breath at the surface, hold it, and dive to depth, then return to the surface still holding your breath. In this scenario, there is no danger of an embolism since compressed gases were not introduced into the lungs.

I think we can all now agree that diving in the absence of proper training is a very dangerous thing to do. I think we can also agree that building ones own diving rig is not small undertaking and care must be taken to use equipment and materials that are up to the intended task. Beyond that, I also think we are, at this point, beating a dead horse.:)
 

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Ill stick with my Kirby Morgan thank you
A GREAT piece of equipment! However, it is designed for commercial divers and this thread is all about hooka diving. Most of the people here are just doing a little light maintenance like hull wipe, inspecting or zinc changes. or maybe they are more interested in looking at pretty fish.

You, on the other hand are a working guy and diving is basically your way of getting to work.
 

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Really, dont ever use a normal air compressor for an air source. First off, commercial offshore diving services all use deisel dive compressors that have various engines (325, all the way up to 5120's) which the output in volume at depth is calculated by a very knowledgeable person. Second, they are specifically designed with water traps( air filters) to screen out that bad **** such as bugs, rust, you name it. Thirdly, they use two oils. One.for the engine that powers the air pistons and then a breathable synthetic oil for the actual lubrication of the pistons. You can buy seperate volume tanks, engines and compressors to piece them together which would be alot cheaper then paying 8 grand on a beat down 325.
Also. Another alternative would be just to get an airpack of hp bottles. You can rent whatever medium youd like however at 14 ft - 50 foot youll only need air, unless you do inwater deco stops using 02. Thats a whole nother ball park. Get yourself two hp bottles, have them professionally inspected. Then order 3/8' inch air hose for a dive umbilical. Youll need a air regulatlor for the bottle manifold and of course the second stage for your mouth. If you call divers supply in belle chase la they can tell exactly what you needs. The hp air bottle rack is always emergency air for divers offshore. This would be a more realistic way to surface supply dive without spending a fortune.
 

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Really, dont ever use a normal air compressor for an air source.
All commercially-available, recreational-level hookahs are based on repurposed oilless air compressors and they are 100% safe for surface supplied air. Virtually the entire hull cleaning industry uses them and has for decades. I have been using various rigs I've built myself for over 18 years and 20,000+ dives. To infer that it is unsafe to use any air source that hasn't been vetted by the hard hat commercial dive industry is ludicrous. The guy is talking about cleaning his boat bottom, for Christ's sake. He doesn't need an $8000 diesel compressor.
 

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My limited understanding is that all of the modern "oil-less" compressors are in fact oil free (except possibly manufacturing/machining traces) because they use teflon rings instead of oiled ones. And that is why the small tire-inflator types easily overheat and burn out, from the teflon melting if they are run too long.

Not a question of oil type of quality, just a different piece of equipment that simply does not use oil at all, so it can't contaminate the airflow.

Assuming it has properly cleaned of manufacturing traces during assembly.
 
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