I've got a few 3" steel pipes to cut about 1-2 meters under the waterline. It's a bit too deep to do it with a snorkel so I'm considering getting a 0.5l scuba thing you can fill with a bike pump so I can go at it with a hack saw. Got any other ideas? I
>>2922880 (OP)>I'm considering getting a 0.5l scuba thing you can fill with a bike pump so I can go at it with a hack saw.That's going to give you what, maybe four complete breaths?
>>2922880 (OP)>Got any other ideas?abrasive blade on an extended shaft weed eater
>>2922881 It's supposed to give 10 minutes of autonomy
>>2922884go on
buy a pneumatic angle grinder from your local hardware store
just hold ur breath for 30 seconds at a time
>>2922880 (OP)https://presearch.com/images?q=cs%20unitec%20pipe%20saw#view
>>2922880 (OP)Curious what these underwater pipes you are talking about are used for?
>>2922880 (OP)just use a couple hoses with check valves, one for fresh air and one for exhaust
>>2922912>German sawFuck it op, go full retard and get a clamshell, you can cut and bevel it at the same time.
I'd do this
>>2922902 or get a longer snorkel and have a buddy make sure it stays above the water line. But just holding your breath you should be bale to get through 1 pipe in less than 10 minutes. Don't forget to support at least one side of the pipe and cut it so the other section drops without binding up your cut off wheel. I had to cut through a 2 inch sc160 with a fucking hacksaw in an scba and that only took me about 5 minutes, a Metabo will do good for you.
Got access around the entire pipe? If so use a regular pipe cutter.
Make a box large enough to fit you but don't put a top or bottom on it. Lower it to right above the spot you need to cut and pump the water out. Keep the pump running to make sure it doesn't feel back up with water. Also make sure it's secured because if it rolls you could easily become disoriented, stuck and die.
Or find a cast iron clawfoot tub, plug the drain hole and use it as a diving bell.
>>2922891>It's supposed to give 10 minutes of autonomyAn 80 L cylinder at 3000 psi would give you a couple hours at 2 m. You can't stuff enough air with a bike pump to get 10 minutes.
>>2922919You ever tried to breathe through a pipe underwater? More than 3 feet or so and the water prevents your diaphragm from working normally. You literally cannot inhale. The input pipe must be pressurized.
>>2922880 (OP)Water proof rotating blade?
>>2923318You mean lbuy one of these and blast The Prodigy at it?
Two meters isn't that deep, could you just use a reciprocating saw with a long blade? Given the pipe is only three inch.
Other options, you break the pipe with a pneumatic hammer and a extended bar.
You break the pipe with a bottle jack. Probably way faster.
You could attempt to use a chemical agent, a wax tube with a reactive oxidiser. Kind of like a thermite line but without the heat.
You could use a regular pipe cutting die, and just use a rope to cut back and forward, cutting through a small section at a time.
You could use a heat deferential, wrap a rubber ring around it, then hit it with liquid nitrogen in a pump tube.
Could could instantly depressurise the pipe with a propane flare out. So put immense suction pressure on on the pipe.
You could try using an arc welder on a pole, great way to electrocute yourself.
There's thermate but it's notoriously hard to use in marine environments
>>2923241You don't want to be trapped underwater in a tube. You might do this to get a cutting torch down.
>>2923318>wire saw?Underrated post. That's what I'd do. Long ass wire saw, nigger rig plank across pipe where you want to saw. Then dive in, thread wire saw underneath pipe, pull up all the way to plank, stand or kneel on plank and saw away. If you've got nowhere to lay plank, drive in two posts for either end of a boat to butt up against (to keep boat clear of wire saw), tie ends of posts to boat and saw away while kneeling in boat.
