As hackers, our goal is to reuse something in a way in which it was not intended and [Rulof Maker] is a master at this. From his idyllic seaside location in Italy, he frequently comes up with brilliant underwater hacks made of, well, junk. This time he’s come up with a wind-powered pump to move air through a hose to a modified scuba mask.
The wind turbine’s blades look professional but you’ll be surprised to see that they’re simply cut from a PVC pipe. And they work great. The air compressor is taken from a car and the base of the wind turbine’s tower started life as a bed frame. As you’ll see in the video below, the whole setup is quite effective. It would have been nice to see him using his leg mounted, beer bottle propulsion system at the same time, but the air hose may not have been long enough to make good use of them.
A breathe of fresh air for sure
“[the base] is almost high like me, 2 meters.”
B^)
The blue stripes on the blades was a nice touch.
And I’m glad he didn’t wear Speedos for the video.
…perhaps a filter on the pump intake?
I’d hate to inhale a bug, or bird poop.
PCB Pipe? That could end poorly.
PVC pipe, prolly.
I knew that didn’t look right for some reason. Fixed. Thanks.
Neat. I am not sure I would try it though. First an old auto A/C compressor has all kinds of nasty oil and refrigerant in it. I am not sure how one would go about totally cleanin that out. The compressor is not designed to be oilless so I am assuming the pistons want or need some kind of lube. Ditto with the air line. I am not sure what I would be comfortable breathing through, but that hose looked a bit sketchy to me. Plus there is the obvious what happens if the wind stops blowing thing, but I guess if it dies down for more than a few seconds you can do a free assent. I would call this one of those things that is cool watching you do, but not quite for me.
It’s not like he was taking it down below 10 m or so — how long was that hose? When the bubbles stop bubbling, all he has to do is swim up.
I hear you about the lube filter, and that wouldn’t be all that hard to add inline either.
The free ascent is not a big issue, but it is an issue to be aware of. The issues to me are air contaminating crud left in the compressor and crud de gassing in the air hose. I am picky about what I breath.
Some compressors can be oil-less but perhaps not that one.
However it’s not pumping against pressure so it’s not under huge load.
It’s not going to be used continuously for a long time.
The fan is cooling it :)
A junk compressor is about $10 so who cares.
Using one as an air compressor on a tank to make 150psi to run tools is quite different to having one “wind milling” under near zero load.
Those junk ebay car tyre air compressors which take 30mins to do a car tyre are oil less too and seemingly last through a torturous life and go feel how hot they get.
Those little tire inflators don’t have an oil sump but they most definitely have a bunch of oil on them. That probably wears off pretty quickly but they are not designed to pump air for breathing. They also move almost no air in terms of volume. On the car compressor it is not so much running it without oil but getting all of the old oil and nasties out of it. For more air volume you could just use an old lawnmower engine with a bit of a mod, but do you really wanna be breathing all the crap out of that, even after a good cleaning?
It is pumping against pressure. For every ten meters deep you go, you are pumping against and additional one atmosphere is pressure. The biggest danger is contamination of the air with any kind of lubricant and how regulated the output pressure of the system is. Real scuba systems use a primary high pressure regulator that drops to an intermediate pressure and a secondary lower pressure regulator that brings that down to breathing pressure with demand controls. In an easy breathing system, this is necessary since there is a fine line between a free flowing regulator (uncontrolled air release) and one that requires too much effort. If the input pressure to the secondary is kept constant it is really easy to tune.
One ATM is what, not even 15 Psi? And he’s not even going 4m deep. For a compressor designed to pump at pressures of 400+psi and in the heat of an engine bay, this compressor is seeing literally zero load. Just look at the extremely small displacement of those pistons.
yet another suicidal scuba project on hackaday…
Another? You realize SCUBA was all DIY from surplus tanks and oxygen regulators until probably the late 60s and 70s.
A lot of the early scuba pioneers were met with pretty grim fates. This seems like a high risk, low reward project, especially when there are such easily attainable and safer alternatives. I hate to think of the consequences for neglecting something here.
More like Early 50’s. Cousteau invented the SCUBA in 1942 and thought up “Aqua-lung” as a commercial name. They started exporting them in the late 1940’s. The surplus parts you would occasionally see were the tanks. I had a pair of O2 tanks from aircraft so I could afford a brand spanking new Scubapro MarkV.
I want to see some old 6351 alloy tanks get shot to see if they’ll explode. If it wasn’t a steel SCUBA tank in “Jaws” it would have been one made of 6351, not 6061. 6061 had been used in high pressure tanks in aircraft as far back as WW2, but commercial SCUBA gear was still available with 6351 tanks into the 1980’s. https://www.youtube.com/watch?v=hsSjwG1b4u4
The problem with shooting some of those old tanks is getting someone to certify them to be filled to pressure, then getting someone to fill them. Would have to find people who’ll accept an explanation they’re going to be destroyed, not used for diving. They maiht want to come along to see their (hopefully catastrophic) destruction.
Get it on video and finally put to bed whether or not a period appropriate aluminum SCUBA tank would or would not blow up the shark in the original “Jaws” movie. We know steel or 6061 tanks wouldn’t because several people have shot those types and claimed their non-explosions as “proof” that the movie scene couldn’t happen – yet nobody has (AFAIK) shot any pressurized 6351 tanks.
As a qualified diver I am pretty sure this guy will become a statistic. I would not try to develop my own surface air delivery systems. Not worth the risk.
Without people like that you wouldn’t have a job in the first place. :)
The people who did that in order to eventually develop SCUBA gear were working at the cutting edge of knowledge and technology. This is not the same at all.
They did it in a military capacity – 1942.
It did not seem to be a military project:
https://en.wikipedia.org/wiki/Aqua-Lung
This is not an invention that builds on the state of the art. This is a cheap hack to replace a commercially available product. Diving is dangerous enough with a lot of unknowns (like a complete theory of decompression illnesses) that resorting to junk like this is not helping anyone.
No decompression needed with this. Stay less than 30 feet deep – or use a 30 foot hose – and dive all day. Evinrude sold these. Wish I had one. https://www.youtube.com/watch?v=n6sZBvQB3MI
Wait – nobody has complained that he shouldn’t be using the word scuba for this project? (Since it’s not self-contained.) I thought there were too many HAD readers with a pedantic bent to let this slip by. I’m impressed, way to go!
They’re shadow Banned
Whoa! I think he is exposing himself to sand and what next, lead?
He said it was “dangerous”, which is right! There are safety issues that may not be so obvious to non-divers such as: the air coming out of the hose at depth is compressed higher than atmospheric pressure, just like the air coming out of a scuba tank. This air then expands in the lungs on surfacing which can cause lung rupture if the pump happened to fail and you decided to hold your breath when swimming to the surface. Also, breathing that air at depth causes gases such as nitrogen to dissolve into the bloodstream, which causes bad things if you surface too quickly, allowing it to abruptly come out of solution. It would be prudent to take a scuba class and research all of the safety issues of breathing compressed air at depth, as they are often not intuitive to many of us land dwellers. Even the shallow depths shown (3 meters) or swimming pools can cause decompression sickness (just do an Internet search for “shallow water bends”).
I’m not dismissing your point on diving as I’m no expert diver.
But this is not compressed air.
It’s pumped air.
There is no vessel with a valve holding the air under pressure, it’s a pipe in a leaky mask.
The “air compressor” is merely pumping the air down said open pipe.
It’s pumped to the same pressure as the surrounding water. Thus it’s compressed compared to atmospheric pressure.
Even though it is not compressed in a tank it must be compressed to an equal or greater pressure of the surrounding water to exit the tube and fill your lungs. The only time it wouldn’t be compressed is if pressure on the outside is matched by the elastic compression of a pressure vessel, such as a submarine, or sealed pipe extending into the water. A human is essentially a bag on the end of a pipe so you need air matched pretty close to ambient pressure to float the line between deflated and blown up. Even diving regulators deliver air at a pressure that is only equal to the surrounding water pressure. Given that this is bubbling it’s a greater pressure than a regulated supply.
With that being said, the guy is as at depths that people normally decompress at, unless he spends several hours with the hose fully extended then immediately comes up to the surface he will probably be ok. Just limit your total time spent diving and spend more time at a shallower depth than the accumulated time below that depth.
One atmosphere (100,000 pascal) for every 33 feet/10 meters of sea-water depth.
Rule one. never ever ever under any circumstances hold your breath while using diving equipment. You should always be either inhaling or exhaling. There is no real scientific model of who will get decompression sickness. All the current models are based on Navy data actually tested in the real world by giving guys decompression sickness. The problem is that you can dive completely within the guidance and still get decompression sickness while others that surely were outside the guidance are completely unaffected. If you are interested in the science of it, check out Diver’s Alert Network who sponsors a lot of the civilian research and the US Navy which is the source of the original dive tables and the basis for all the models since.
I didn’t realize that an auto air conditioner compressor was a constant displacement pump (per revolution).
There may be other application to like hydraulics or a water pump even.
What’s the normal output pressure range for these pumps?
I would imagine the valve plate is stainless for it’s lower metal fatigue. Does anyone know what the bore/pistons are made of?
if i recall, i think the compressor pistons were made of aluminum. if you try and pump water and you have a decent amount of torque on the input you’ll hydro-lock it and destroy it. the pressure output is somewhere in the ballpark of 240-ish psi.
Scuba divers are all over-trained safety nazis. Unless you are a moron or prone to panic at the least provocation, there is no way you can’t self-rescue (i.e. swim to the surface) from 10m. I have no problem solo diving at such depths. Yes I know this violates all you have been taught, etc. etc. Yes, I am a certified diver. P.S. don’t hold your breath.
When I was a kid in high school I found an old A/C compressor and a 1/4 hp motor and it wasn’t long before I had air bubbling out of a hose at the bottom of our pool and was using it to refill my lungs. No kids, you shouldn’t try this at home, only certified experts like myself can get away with this.
One of the most amazing exercises we went through during my certification was breathing by pushing in the button on the reg and letting the bubble rise into our mouths.
Interestingly enough, it’s effortless to separate the water form the bubbles .. I guess we do similar stuff from birth (drinking without drowning, breathing without drowning in our own saliva etc.) .. so underwater breathing apparatus can be pretty simple in a pinch.
There are lots of morons then because there are plenty of diving accidents every year in 10m of water or less. You can’t self rescue if you are unconscious from breathing from a contaminated air source. I also would love to see the 1/4 horse motor that was driving your A/C compressor. Thats the most impressive quarter horse I’ve ever seen.
The 1/4 hp motor in the above comment was driving a mostly unloaded AC compressor. I have no doubt that said motor could turn it while acting as a 5psi low flow pump.
I have seen many documentaries of divers that use little more than a regular air compressor and a plain hose with no regulator.
I am also an open water certified diver.
I am sure as heck never going to use any thing like that.
Yes it could be refined with a proper compressor with an emergency backup tank just in case something fails.
Just pulse the emergency air every 5 seconds to warn the diver that they are on backup air and to make a safe emergency ascent. .
Not much different than a gas powered floating dive air compressor for multiple divers. Most of the times it is for divers wearing helmets.
I have seen them in resorts in Jamaica.
And at one of the water parks in Florida. My wife an I did a little “dive” experience with them. (Since she is not a diver.)
I just had to keep fighting the urge to try to swim. You have to keep you head vertical or the trapped air in the helmet would bubble out.
My wife and I did the helmet diving thing in Bermuda many years ago (they called it bell diving). The most interesting/unsettling thing I noticed was how the water level in the helmet would rise each time I took a deep breath.
“All I needs is four stout men to work the bellows.” Not no more Grandpa!
Well, this video brought a smile to my face, the way he just uses things he has found on the streets etc, and then just cobbles them together – and it looks nice too!
I know, I know, not as safe as not going under water at all. But on the other hand – he’s not overpressuring the air. Because the air is pushed under force from the surface, and he has holes in the mask, the air is necessarily at the same pressure as the water depth.
As long as he stays within a few meters and doesn’t go too long, he’ll be fine.
Yea, I agree well done and good video. Rulof made it clear it was a bit of fun. Good on him.
In addition to the constant fresh air supplied, the positive pressure would probably keep water from seeping in to the mask. This is awesome.
Two additional problems
Poorly lubricated compressors generate carbon monoxide, as in carbon monoxide poisoning
A substandard non-return valve could result in catastrophic negative pressure inside the mask, as in sucking your lungs out of your chest catastrophic, this occaisonally happened to “hard hat” divers, when their compressors failed they died
How exactly would a wind powered compressor generate carbon monoxide? I call bullshit.
And the second argument is nonsense as well. Have you even seen the video?
The adiabatic compression raising the temperature of air in the cylinder past the auto-ignition point of any residual lubricants. Due to the increased partial pressure at depth, many things that are safe at sea level become toxic at depth. Oxygen for example can induce pulmonary and/or central nervous system toxicity (effectively buring your lungs or causing a seizure) Small levels of CO in a breathing gas is no joke. The standards for SCUBA state less than 10 ppm CO.
the adiabatic pressure rising above auto ignition point. In other words: that is never going to happen with this windmill.
Specifically the lubricant can break down under high enough heat and produce carbon monoxide. However… I’m not really certain that this wind powered compressor is operating at such extremes that this is really a concern. I would imagine it would be a bigger problem if the air intake sucked up the exhaust from a nearby gas/Diesel engine which… of course is unlikely here.
I have no comment about the return valve.
Makes me think of Thomson and Thompson pumping away (or not) at the diving compressor in ‘Red Rackham’s Treasure’.
I was reminded of the same thing. Poor Thomson and Thompson. They sure got a good workout though.
I just got a boxed set of Tintin the other day, looking forward to watching it again.
Nope!
I just don’t see how you can clean out a car A/C compressor to the point that it is safe to use as an air supply. Hopefully all the refrigerant was removed properly before he even arrived at the junk yard but I am thinking that there will always be a little oil in there no matter what he does and it will be slowly but constantly off-gassing right into his lungs.
Then there’s that hose. It looks like a used compressor hose such as one that would be used with air tools. No doubt it has had oily air ran through it in the past too.
Uh uh, not for me. I know we all die eventually but I have witnessed enough cancer deaths to know that all deaths are NOT equal and cancer is NOT the way I want to go!
There are my only two concerns.
I don’t know what is used for lubricant in an aircon compressor but I do know that many auto lubricants produce carcinogens when they have been heated. I would imagine though that there would be a relatively simply way to clean the compressor of the previous contaminants.
The hose is another story. It if was previously used on a lubricated air compressor then these would be oils in the hose that are bonded to the internal surface and would be near impossible to clean out.
Even the material the hose is made of, may emit other toxins. Of course you can buy safe hose but it would be expensive.
So, does that A/C compressor use a swashplate to run the pistons?