Diving contraption.

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burgundyben

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Is there such a thing that allows a berk to dive into the water while at anchor or in port, with an air supply that's fed from a pump on the deck? To a depth of just a few feet for scrubbing the bottom or clearing the prop?
 
I think circa 500quid buys you a kit with a dockside (or deck if you wish) pump (12V or 220V) with no oil etc on the air, 10m or so of pipe and a regulatorish thing. All horrible yellow coloured.
Had them bookmarked but cannot find them now, ebay is full of that but mainly from the US

V.
 
I had a go with the Peter Diving System whilst in Mallorca last year. Was quite fun. Looks to be in the same class as "hookah diving" of the tank-on-a-float variety rather than a surface pump. Not sure where you're based but if in the Med you can probably find a place with Peter Diving System to try it out. I did it at Punta Negra near Portals.
 
Whatever you do (or let your kids do) DON'T go underwater with just a pipe in your mouth, with the other end open to the atmosphere. ESPECIALLY with a weight belt to keep you from surfacing.

I tried it once as a kid in a swimming pool and damn nearly died. The pressure difference between the open air and water at only four feet was totally terrifying in that all the air in my lungs was forced out in a split second.

I was lucky.
 
Have a look at Mini B, great bit of kit for shallow diving say a few metres for e.g. cleaning the hull. As with anything like this, make sure you get the proper training such as Padi, Bsac.
 
burgundyben said:
Oh! right! I was just gonna dive in!
Click to expand...

I did

In 3 m of clear blue water .

First without the belt then with it cos without you tend to float to the surface and waste energy trying to sink .
Remember somebody telling me kids had to be around 14 - something to do with delicate lung tissue .
They were so - “ dad ,dad can we have a go “
Sure kids .
We have all snorkelled deeper btw and I think kids did diving training @ school - Olympic free board stuff so been deeper than 4 M .

Really just fit n go , there’s a guage .
Ideal for a less strenuous way of cleaning the sterngear.
Bottle in SoF is €4 refill at a dive shop on the marina and every 2 years in Fr the bottle is sent away for a pressure / corrosion test - kinda MOT and the ex date stamped on when it returns 4 days later costs about €40 .

I got it mainly for clearing fouled ( pot ) stern-gear in an emergency.
But use it to phaff under the boat now the novelty of chasing octopus clams and gropers has worn off:)
 
Portofino
It beggars belief where you stow all the equipment you have, Not once have you informed us what marvelous storage there is on an Itama!
Clear it out for another 10 knots!
 
Re: Diving contraption

stelican said:
Portofino
It beggars belief where you stow all the equipment you have, Not once have you informed us what marvelous storage there is on an Itama!
Clear it out for another 10 knots!
Click to expand...

Did do when I got it came with 16 life jackets, some still in wrappers - gave them to local kids sea school .
Far to many warps and mooring chains - gave those away ,

Dive kit
It’s only 6 kg and about 1/2 the size of fgt cabin bag when all packed easily into its bag .
Fits in the dead corner of the L shaped kitchen / galley - amongst the bottle s of red and rose store .
Wine on board weighs more :)

4.2 M beam means plenty of storage all the seats in the vast cockpit have lift off access panels as they are on top of the engine room .
You see no accommodation underneath the cockpit as true mid engine .Most other competitors have a rear cabin accessed from the saloon and the cockpit seats are actually part of the headroom so no storage .

Got a spare pair of props under one of the rear cabin bunks - about as large as a Range Rover wheel each .
Sorry no pics of that one .
Over and above normal under saloon seats and master cabin bunk ,there’s a few nice storage touches

https://imgur.com/a/W6jey
 
Re: Diving contraption

Like Portofino I also find it useful to be able to do cleaning and maintenance under the boat whilst floating in clear safe water. I investigated the hookah system and it is not as simple as i hoped it would be. A normal scuba regulator has a two stage system. The 1st stage (that screws onto the top of a diving cylinder) takes the pressure from in the bottle (can be as high as 300 bar ) and reduces it to 7 to 9 bar so that you don’t burst a lung with a squirt of incredibly high pressure air..... something that I suspect stings a bit...... the air supply is then constant at any depth (assuming one observes natural and very logical depth restrictions) so that by the time the air reaches the mouthpiece (which is stage 2)it can be reduced further to whatever pressure you need to suck it into your lungs (one or two bar max). That regulator system works as well on a compressor as it does on a cylinder.
The problem with a compressor is that it has to be pretty powerful to provide enough pressure to allow that 1st stage to work efficiently down to a depth of say 20m. Which you clearly wouldn’t need for Boat maintenance. This is why the ready made hookah systems are so expensive.... the compressor is powerful, the filtration system has to be effective (your life depends on it) and the lubrication must not be oil based as that residue, if breathed can kill you...... powering the compressor is another issue..... if it’s big enough to do the job down to 20m then 12 volts won’t cut it, so you either need mains or a petrol engine..... that then leads to further complexities.

In truth you could build some sort of cobbled together 12volt compressor to give enough air to breathe at 2 or 3m, and youtube is full of the sort of contraptions I am talking about....... however the chances of doing yourself some serious harm most probably from the quality of the air you would be feeding yourself, but also possibly from lung damage, that I think you’d be a loony to even try.

SO ..... Portofinos solution is to use a cylinder ( a normal diving bottle) and, if I’ve understood correctly, he uses a very long regulator hose from the bottle so that he doesn’t have to carry it with him....... however he is technically diving with a scuba tank and I think the OP was interested in a compressor. Porto is hookah breathing In the sense he doesn’t carry his tank with him. But the actual point of the compressor is to give unlimited air supply so that divers, like baloney divers can dive at very shallow depths for very long periods of time without concerns over air supply.

My opinion for what it’s worth, and what I actually have done, is to buy a good quality 12litre cylinder (a much smaller one of just 3 or 7 litres are also available and much easier to stow and handle and would be plenty at shallow depths to do any conceivable underwater job) on eBay for £100, have it tested and certified (£35). And I have also bought a regulator set on eBay, £75 and had that serviced and certified (£70). And a simple backpack (£16)...... I carry the tank on my back, whilst Porto doesn’t, but I’d prefer to have my captive air supply with me than to have it elsewhere and I didn’t fancy the additional cost of the long hose I would need when it’s only for occasional use.

Finally, and at the risk of bleating about elf and safety, Please don’t underestimate the damage you can do to yourself underwater. An air embolism can form in just a few metres of depth (1 m of depth roughly equals 1 bar of pressure), And you can drown in any amount of water ....... so even though I broadly agree that you’ll probably be ok with a bit of common sense I would still much rather that, for the sake of a short course, anyone using this kit under water gets some sort of training, Even if it’s just reading the text book and learning about what not to do from someone who knows, then that’s much better than nothing !!! I am a certified diver who has dived all over the world for the last 35 years and I am always astonished when anyone is in the camp of “well what can possibly go wrong”? The biggest issue is that underwater there are no small problems..... so please don’t be too casual !
 
Last edited:
Re: Diving contraption

Boatbore said:
Like Portofino I also find it useful to be able to do cleaning and maintenance under the boat whilst floating in clear safe water. I investigated the hookah system and it is not as simple as i hoped it would be. A normal scuba regulator has a two stage system. The 1st stage (that screws onto the top of a diving cylinder) takes the pressure from in the bottle (can be as high as 300 bar ) and reduces it to 7 to 9 bar so that you don’t burst a lung with a squirt of incredibly high pressure air..... something that I suspect stings a bit...... the air supply is then constant at any depth (assuming one observes natural and very logical depth restrictions) so that by the time the air reaches the mouthpiece (which is stage 2)it can be reduced further to whatever pressure you need to suck it into your lungs (one or two bar max). That regulator system works as well on a compressor as it does on a cylinder.
The problem with a compressor is that it has to be pretty powerful to provide enough pressure to allow that 1st stage to work efficiently down to a depth of say 20m. Which you clearly wouldn’t need for Boat maintenance. This is why the ready made hookah systems are so expensive.... the compressor is powerful, the filtration system has to be effective (your life depends on it) and the lubrication must not be oil based as that residue, if breathed can kill you...... powering the compressor is another issue..... if it’s big enough to do the job down to 20m then 12 volts won’t cut it, so you either need mains or a petrol engine..... that then leads to further complexities.

In truth you could build some sort of cobbled together 12volt compress to give enough air to breathe at 2 or 3m, and youtube is full of the sort of contraptions I am talking about....... however the chances of doing yourself some serious harm most probably from the quality of the air you would be feeding yourself, but also possibly from lung damage, that I think you’d be a loony to even try.

SO ..... Portofinos solution is to use a cylinder ( a normal diving bottle) and, if I’ve understood correctly, he uses a very long regulator hose from the bottle so that he doesn’t have to carry it with him....... however he is technically diving with a scuba tank and I think the OP was interested in a compressor. Porto is hookah breathing In the sense he doesn’t carry his tank with him. But the actual point of the compressor is to give unlimited air supply so that divers, like baloney divers can dive at very shallow depths for very long periods of time without concerns over air supply.

My opinion for what it’s worth, and what I actually have done, is to buy a good quality 12litre cylinder (a much smaller one of just 3 or 7 litres are also available and much easier to stow and handle and would be plenty at shallow depths to do any conceivable underwater job) on eBay for £100, have it tested and certified (£35). And I have also bought a regulator set on eBay, £75 and had that serviced and certified (£70). And a simple backpack (£16)...... I carry the tank on my back, whilst Porto doesn’t, but I’d prefer to have my captive air supply with me than to have it elsewhere and I didn’t fancy the additional cost of the long hose I would need when it’s only for occasional use.

Finally, and at the risk of bleating about elf and safety, Please don’t underestimate the damage you can do to yourself underwater. An air embolism can form in just a few metres of depth (1 m of depth roughly equals 1 bar of pressure), And you can drown in any amount of water ....... so even though I broadly agree that you’ll probably not be ok wi5 a bit of common sense I would still much rather that, for the sake of a short course, anyone using this kit under water getsome sort of training, Even if it’s just reading the text book and learning about what not to do from someone who knows it’s better than nothing !!! I am a certified diver who has dived all over the world for the last 35 years and I am always astonished when anyone is in the camp of “well what can possibly go wrong”? The biggest issue is that underwater there are no small problems..... so please don’t be too casual !
Click to expand...

Great post, thank you.
 
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