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Underwater Chain Saws

stanleyinfrastructure.com

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Re: Underwater Chain Saws

#51

Post by jojobas »

Daub wrote: post #12
CBLT wrote: post #2

From the user manual on that page: > Maintain proper footing and balance at all times. Is this not supposed to be used in deep water? Or am I just swimming wrong?

Former chainsaw operater speaking. I cant imagine easily using a chainsaw underwater for the every action has an equal and opposite reaction thing. However, I notice that the front spikes on the saw are noticably big. When these are dug into the timber, they offer a fulcrum using which the operator can apply force onto the timber. This could lessen though not negate the issue. I gave up chainsawing the day I accident…

Put enough lead on yourself and it's much like on the surface. You don't swim with a chainsaw.

Re: Underwater Chain Saws

#52

Post by RetroTechie »

dig1 wrote: post #43
chubs wrote: post #9

Around $4100! https://www.amronintl.com/stanley-cs113no-hydraulic-underwat... Amazing how capable tools can be, in industries that simply cannot get their work done without them and are willing to pay a healthy amount. Sometimes I wonder how good our dev tooling would be if we were willing to pay thousands a year, as opposed to the time-wasting bug-fest that is Xcode. Not singling out Apple, I’m sure all are comparab…

I can imagine why these things are expensive, as someone who occasionally cleans the local Olympic pool using an underwater vacuum cleaner (just a side gig to get free diving time). Salty or chlorinated water (and public pools usually use heavily chlorinated water) will dissolve almost anything over time - I've seen chlorinated water eat through plastic or neoprene in 2-3 years of use. Account to that mentioned vacuu…

> Salty or chlorinated water (and public pools usually use heavily chlorinated water) will dissolve almost anything over time

Metals, in particular. This is why in marine environments, special grades of stainless are used. Most commonly SAE 316 alloy (often marked with "A4", vs "A2" for regular stainless).

Another approach is the use of sacrificial anodes.

Where practical, it helps to rinse equipment with fresh water after use.

Re: Underwater Chain Saws

#53

Post by jojobas »

rocqua wrote: post #46
steve_adams_86 wrote: post #36

Earlier quoted context omitted.

I wonder if you’d get issues running an ICE under water if you went very deep, due to pressure changes on the exhaust system. Assuming you could seal up the system well enough to work at depth, and provide O2 as you mentioned. Even the pressure going into the combustion chamber could be a complicated thing, right? Say you’re at 20 feet, that’s a fair amount of pressure. But what if you’re at 80 feet? Would it still b…

If you can push the fuel and air in at ambient pressure, it shouldn't matter much right? Because the 'neutral' point of the cilinder pressure would be just as high as the pressure of the exhaust. You'd probably lose some efficiency because the difference between peak pressure and neutral pressure in thr cylinder feels like it would be smaller. Perhaps not, because you could fit much more fuel and air in the cylinder…

Most of your engine's power will be spent pushing the exhaust into the water.

Re: Underwater Chain Saws

#54

Post by psd1 »

tempodox wrote: post #44

Great, that opens up under-water scenarios for computer games where the protagonist can pick up a chain saw.

Doom 3 had a great journal entry to discover: "We requisitioned a crate of jackhammers, and the idiots sent chainsaws! What use is a chainsaw on Mars?"

Re: Underwater Chain Saws

#55

Post by gpderetta »

ek_erilaz wrote: post #34
anjel wrote: post #21

While gas / electric chainsaws are unlikely to work underwater, I can't imagine a reason why a hydraulic chainsaw wouldn't work on dry ground with its superior weight to power ratio and lack of blue smoky exhaust. Probably quieter too.

Your intuition was spot on! I used to cut concrete for a living, and we had several hydraulic chainsaws. The torque on those things was incredible. They were quieter than gas chainsaws, even factoring in the diesel-powered hydraulic pump in the trailer nearby. The main drawback, as other commenters mentioned, was portability. The saw itself was shockingly light (which made the torque that much more surprising) and po…

Thanks for the colorful description! I'm always amazed by the variety of backgrounds of people commenting on HN

Re: Underwater Chain Saws

#56

Post by jacquesm »

ek_erilaz wrote: post #34
anjel wrote: post #21

While gas / electric chainsaws are unlikely to work underwater, I can't imagine a reason why a hydraulic chainsaw wouldn't work on dry ground with its superior weight to power ratio and lack of blue smoky exhaust. Probably quieter too.

Your intuition was spot on! I used to cut concrete for a living, and we had several hydraulic chainsaws. The torque on those things was incredible. They were quieter than gas chainsaws, even factoring in the diesel-powered hydraulic pump in the trailer nearby. The main drawback, as other commenters mentioned, was portability. The saw itself was shockingly light (which made the torque that much more surprising) and po…

I've used one of those to cut a doorway in a concrete wall. Initially I tried doing this using a very large cutting disc but it wore down the disc so fast that it would have required passes from both sides. The saw did the work in a fraction of the time and made a cleaner cut than the disc, which I had not expected. You want to really plan your cuts though, if it should get pinched it probably would be quite impressive.

Re: Underwater Chain Saws

#57

Post by Cthulhu_ »

chubs wrote: post #9

Around $4100! https://www.amronintl.com/stanley-cs113no-hydraulic-underwat... Amazing how capable tools can be, in industries that simply cannot get their work done without them and are willing to pay a healthy amount. Sometimes I wonder how good our dev tooling would be if we were willing to pay thousands a year, as opposed to the time-wasting bug-fest that is Xcode. Not singling out Apple, I’m sure all are comparab…

That's the weird thing about software development, it can be done on a small budget. But large companies will find ways to spend money, i.e. by using loads of CI servers on AWS.

Re: Underwater Chain Saws

#58

Post by avidphantasm »

It amazes me how much we’ve figured out how to do underwater. For instance, cement! Now chainsaws! Although I imagine using a chainsaw while scuba diving would probably violate the terms of my life insurance policy. Paradoxically, it may be safer than using one on land; the kickback should me much slower do to the density of the water.

Re: Underwater Chain Saws

#59

Post by tempodox »

psd1 wrote: post #54
tempodox wrote: post #44

Great, that opens up under-water scenarios for computer games where the protagonist can pick up a chain saw.

Doom 3 had a great journal entry to discover: "We requisitioned a crate of jackhammers, and the idiots sent chainsaws! What use is a chainsaw on Mars?"

True, I remember this.

Re: Underwater Chain Saws

#60

Post by MichaelZuo »

theamk wrote: post #38
chubs wrote: post #9

Around $4100! https://www.amronintl.com/stanley-cs113no-hydraulic-underwat... Amazing how capable tools can be, in industries that simply cannot get their work done without them and are willing to pay a healthy amount. Sometimes I wonder how good our dev tooling would be if we were willing to pay thousands a year, as opposed to the time-wasting bug-fest that is Xcode. Not singling out Apple, I’m sure all are comparab…

I worked at the company which used a proprietary compiler, IDE including debugger.. It was few thousands $ I believe. plus about the same amount for their proprietary JTAG adapter. Worst software I ever used. Crashy, slow, critical features missing (example: debugger can show thread list... but not the stacks of other threads). So no, I would not expect expensive commercial software to be better. It might generate 2%…

But at least the vendor would guarantee, in writing, some minimum baseline of performance?
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