I have just purchased an Antlia oil free compressor, mainly for touch up jobs on my Roberts Spray, away from the marina.
These compressors haven't been out long and in Australia retail for $299, although I got 30% off last Saturday at Repco.
Model No AN20210F.

60L/min free air delivery, max pressure 115PSI, draws 550w so I can power it with a 1KVA Honda on board (or in the tinny). The compresor unit with tank and all fittings weighs 22kg, so it's quite manageable.
It is very quiet and works a little touch up gun, no worries.

My question: with the correct filters (open to suggestions), a 100PSI regulator and about 20m of dive hose, does anybody see this unit as a problem for diving to check the hull and clean the prop. The boat only draws 4'4", but I realise poor air and any operation, even at 5ft depth, does carry potential dangers. I previously (in the 80's, before licences came out) used scuba for commercial collection of saltwater aquarium fish in Queensland where I live.

I know nuttin, but mate, would you bet your life on a bit of mechanical gear (probably from a large former kingdom) that you bought for $299 less 30%?

Keppelyachty,

That compressor has insufficient volume to be used by a diver.

You will need a DIAPHRAGM compressor with at least 120 l/min to be usable in diving.

While it also says oil free, you will need an filter capable of removing oil.

Mate of mine actually tried this with a comparable compressor, didn't work!


Well at least you have brought a good pump for all your car tires etc

Diaphram pumps are better but piston oil less will be fine. The only problem I can see is the high pressure will create heat and a metre of the correct heat hose before joining the hookah hose will be required. The capacity is fairly low so a chamber will be required, either a tubular frame to mount the unit on or a floating chamber.
I use one of these pumps - www.gardnerdenver.com/en-au/thomas

Same pump is used in commercially available hookah units and they all use chambers. The photo below is mine. The frame is 1.5 inch SS tube which is the air storage. I have a separate chamber that floats under construction. I have found that I can breath down the capacity particularly in winter or when working. Mate with the same pump has a large chamber and it has transformed the performance. I use a section of pantyhose as the filter!
[URL=.html] [/URL]

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nswsailor said..
Keppelyachty,

That compressor has insufficient volume to be used by a diver.

You will need a DIAPHRAGM compressor with at least 120 l/min to be usable in diving.

While it also says oil free, you will need an filter capable of removing oil.

Mate of mine actually tried this with a comparable compressor, didn't work!


Well at least you have brought a good pump for all your car tires etc

as another person keen to kill himself with a home made hookah made from a compressor from Bunnings (but yet to get around to it)

does one really need a pump output put so high if its just used no more than say 4 meters depth.

I was under the impression that the air flow is dependant on the depth. shallow diving requires less air.

to the OP I'm pretty sure there are loads of people who have built there own diving hookahs, using oilless compressors from hardware stores. just use due diligence and research research research.


get it wrong and you will die.

Very interesting!
I will be looking into making a Hookah set-up from scratch next year too.
If anyone knows some good links or How-to videos please share

Vernon

good topic ............... please keep the info coming. I would like one of these setup too , but , as bubble7777 suggests ....... I DON'T WANT TO DIE !!!!! .......... ever !!!!

keppleyacht.
One point I should make after re reading your post concerns te use of a petrol motor. Ensure the exhaust is well clear of the pump intake. I would not have the generator in the dinghy with the pump. Better to keep it onboard.

First thing.... Make sure that your air intake is well above the exhaust and cannot be knocked down. I know of two guys who died when their dog knocked the air intake into the boat where the exhaust fumes were. (the air intake had a flexible hose as part of it).
Likewise I know of a death where the intake was bumped against the exhaust and the fumes from the melting plastic proved to be toxic.As for the oil, it is not just oil fumes to be wary of but the heat generated can cause the oil to be burnt (albeit just a bit) and produce carbon monoxide. Carbon monoxide cannot easily be filtered out and is very toxic.

I used to run activated charcoal and alumina in my hooka unit, though it was a different set up than what you are trying.Mine is a Honda motor driving a Clisby twin compressor.

Be careful & good luck.

PS. Definitely consider an air receiver as mentioned above.

Her is a shot of the compressor, one side shroud removed to show pump. The capacity is the same as the Powerdive Power snorkel 2cfm, which operates to7m for one diver.

Keep the info coming, much appreciated.
Regards,
Les.

The most expensive part of a unit is the filters, water separation, particle filter and charcoal filters, generally two side by side can cost up to $800, i have built two units, there is no way i would dive without these filters on a hooka, or with a dog in the boat, an observer is always another good way to stay alive!!!!

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keppelyacht said..



Her is a shot of the compressor, one side shroud removed to show pump. The capacity is the same as the Powerdive Power snorkel 2cfm, which operates to7m for one diver.

Keep the info coming, much appreciated.
Regards,
Les.

That compressor is just a twin piston unit similar to what hull cleaners use in the USA on their hookahs. The pistons use nylon rings and run on nylon bearings and there is no oil anywhere. I would prefer a diaphragm pump and low pressure personally. That tank is more than adequate as a receiver.
I'm guessing this is your compressor www.alibaba.com/product-detail/oil-free-air-compressor-promotion_206416244.html?spm=a2700.7724857.29.64.wtWs0V

We have covered this territory previously on a few occasions, here is one example.
www.seabreeze.com.au/forums/Sailing/General/Floating-electric-Hookah/

Plenty of threads on cruiserforums. Here is just one. www.cruisersforum.com/forums/f115/source-of-food-grade-air-hose-for-hookah-setup-150279.html

Take notice of anything fstbttms says as gospel. The only critical item to buy is the hose. Ensure it's food grade and I would suggest one that's stamped as Hookah hose. 20 metres is about $100 and don't use less than 20 metres.

In a former life I was involved in commercial design and manufacture of breathing air compressors and systems so hopefully I can remember some useful info to pass on... I'm not into long explanations so here's the story in point form...

Compressors:
When you compress air it gets hot, eg, as in a bike pump.
The higher the compression ratio, the hotter the air gets. eg in a diesel engine it ignites the fuel.
Restricting the inlet of a compressor will raise the compression ratio and therefore the air temperature.
High air temperatures can generate "nasties" in the output air in all types of compressors.
A diver breathing normally needs about 30 litres/minute of air per 10 metres of depth underwater eg 30 l/m on the surface, 60 l/m @10m, etc..
As the pressure output rises on a compressor the l/m value drops due to inefficiencies.
For every 10m deep, a diver needs another Bar of air pressure, ie, 10m=1 Bar, 20m=2Bar, etc..
So one diver at 10m depth needs at least 60 litres/minute @ 2 Bar.

There are 3 basic types of compressors for Hookah use:

1. oil lubricated (eg Clisby):
- highest efficiency
- single stage is good for 6 Bar
- low cost
- lube oil should be mineral or synthetic but NEVER vegetable oil
- requires high efficiency filtration (expensive) to remove hydrocarbons from the air (using Coalescer, Molecular Sieve, Activated Charcoal, etc)

2. oil-free Diaphragm (eg: Thomas type)
- very low efficiency
- only useful for up to about 2 Bar pressure
- does not need special filters

3. oil-free Piston (eg: Antlia compressor mentioned previously..)
- medium efficiency
- works ok up to about 5 Bar pressure
- does not need special filters
- the piston seal is made from a Teflon compound and can give off a narcotic gas over about 230 deg C which is possible if operating with a high compression ratio due to restricted intake + high output pressure especially in the hot sun. (it does give a "high" but comes with side effects of terrible headaches and possible drowning..)

Hoses:

any engine driven compressor needs care to ensure that the air intake suction hose is at least 25mm ID and is made of metal or rubber, NOT plastic.

For in the water, "Divers hose" is specially made for low-toxicity and it has almost neutral buoyancy so it floats on the surface and doesn't get tangled down under.. Brands are Barfell, Esdan (and others?)

Regulators, also known as "demand valves", are another chapter.. the best type for hookah use are called "upstream tilt valves", the Airdive brand being the best known.
"Downstream" valves, as used with Scuba tanks, are designed for use with a constant inlet pressure of up to 10 Bar which is not possible with hookah. Many people do modify these valves for hookah use but the breathing effort is not consistent and can be very tiring.

And lastly, but most important, is to fit a non-return (check) valve between the demand valve hose and the hose going to the surface! This is the prevent the diver's internals being sucked through the demand valve in the case that the supply hose gets cut or disconnected at the surface!

Hope this all makes sense! (if not, don't try to make a hookah..)

cheers!

Thanks Iancd and everyone,
Ian, a lot of information in as little as words as possible, that's hard to do.

One question, is the demand valve in this setup in your mouthpiece?

Spot on iancd,

But guys, get some dive training before you start as the top 2m of water is the most dangerous!!!!!

Select to expand quote

iancd said..
In a former life I was involved in commercial design and manufacture of breathing air compressors and systems so hopefully I can remember some useful info to pass on... I'm not into long explanations so here's the story in point form...

Compressors:
When you compress air it gets hot, eg, as in a bike pump.
The higher the compression ratio, the hotter the air gets. eg in a diesel engine it ignites the fuel.
Restricting the inlet of a compressor will raise the compression ratio and therefore the air temperature.
High air temperatures can generate "nasties" in the output air in all types of compressors.
A diver breathing normally needs about 30 litres/minute of air per 10 metres of depth underwater eg 30 l/m on the surface, 60 l/m @10m, etc..
As the pressure output rises on a compressor the l/m value drops due to inefficiencies.
For every 10m deep, a diver needs another Bar of air pressure, ie, 10m=1 Bar, 20m=2Bar, etc..
So one diver at 10m depth needs at least 60 litres/minute @ 2 Bar.

There are 3 basic types of compressors for Hookah use:

1. oil lubricated (eg Clisby):
- highest efficiency
- single stage is good for 6 Bar
- low cost
- lube oil should be mineral or synthetic but NEVER vegetable oil
- requires high efficiency filtration (expensive) to remove hydrocarbons from the air (using Coalescer, Molecular Sieve, Activated Charcoal, etc)

2. oil-free Diaphragm (eg: Thomas type)
- very low efficiency
- only useful for up to about 2 Bar pressure
- does not need special filters

3. oil-free Piston (eg: Antlia compressor mentioned previously..)
- medium efficiency
- works ok up to about 5 Bar pressure
- does not need special filters
- the piston seal is made from a Teflon compound and can give off a narcotic gas over about 230 deg C which is possible if operating with a high compression ratio due to restricted intake + high output pressure especially in the hot sun. (it does give a "high" but comes with side effects of terrible headaches and possible drowning..)

Hoses:

any engine driven compressor needs care to ensure that the air intake suction hose is at least 25mm ID and is made of metal or rubber, NOT plastic.

For in the water, "Divers hose" is specially made for low-toxicity and it has almost neutral buoyancy so it floats on the surface and doesn't get tangled down under.. Brands are Barfell, Esdan (and others?)

Regulators, also known as "demand valves", are another chapter.. the best type for hookah use are called "upstream tilt valves", the Airdive brand being the best known.
"Downstream" valves, as used with Scuba tanks, are designed for use with a constant inlet pressure of up to 10 Bar which is not possible with hookah. Many people do modify these valves for hookah use but the breathing effort is not consistent and can be very tiring.

And lastly, but most important, is to fit a non-return (check) valve between the demand valve hose and the hose going to the surface! This is the prevent the diver's internals being sucked through the demand valve in the case that the supply hose gets cut or disconnected at the surface!

Hope this all makes sense! (if not, don't try to make a hookah..)

cheers!

Awesome

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Shaggybaxter said..
Thanks Iancd and everyone,
Ian, a lot of information in as little as words as possible, that's hard to do.

One question, is the demand valve in this setup in your mouthpiece?

I'm not Iancd but yes, the demand valve is in the mouth piece. In my photo above the non return valve is between the black flexible hose and the yellow hookah hose. My mate with the same set up does not have a non return valve and there is some debate as to whether they are needed with a diaphragm pump at the depths we dive at.