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How I got my laser eye injury

funraniumlabs.com

131–140 of 378 posts

Re: How I got my laser eye injury

#131

Earlier quoted context omitted.

I don't have one yet so cant really advise on quality, but I was recently looking and you can pick up a 2.5kW laser welder from about $15k. They are slightly cheaper (around 12k) from alibaba, but then you will be looking at import duties, warranty complexities, etc

Yeah, that's the problem with some of the more expensive Alibaba/Aliexpress stuff. The list price is attractive, but once you add in all the extras like duties, transportation from the port of entry to your location, warranty difficulty etc., there's not much price difference from heading over to the local Kubota dealership. Still, some of those little tracked tractors on TikTok are interesting. If I could somehow ra…

A lot of folks find those little chineese tractors at auctions in the US. There are folks who handle all the import and then resell them. Can be a great deal but many of them need some mods, like better cooling, to really shine.

Re: How I got my laser eye injury

#132
post #99
post #45

Earlier quoted context omitted.

I’ve seen some references to the universal laser glasses: Apple Vision Pro!

No, the cameras would probably not survive laser exposure beyond a cat toy pointer level power (and even then I wouldn't bet long exposure of those).

That’s fine. If I worked in a room with a laser and I screwed up and hit my face, frying an Apple Vision Pro seems like a pretty small price to pay. My eyes will be fine.

And the Apple Vision Pro works against tunable lasers, lasers of unknown frequency, flashlamps, etc.

Re: How I got my laser eye injury

#133

Earlier quoted context omitted.

There's a killer Neal Stephenson plotline in here somewhere. Redneck protagonist zapping enemy drones with a modified laser welder.

Hmmm. I'm black, but my wife did anoint me to the position of "honorary redneck" some time ago. Neighbor has stopped with the drone overflights of my property, but still, you're giving me ideas...

Go get em cowboy!

Re: How I got my laser eye injury

#134

Earlier quoted context omitted.

I get laser safety curtains, but what do you do for reflections off the ceiling? Asking because our makerspace was recently donated a fiber laser welding unit and we don’t yet know best practices for not blinding our membership short of building a completely enclosed separate room for it with door interlocks.

Ideally you have an enclosed area with interlocks. All of the laser welders support it (and it's the standard way). They make and sell mobile ones that can be pushed around. See, e.g., https://lasersafety.com/barriers/rigid-barriers/ for some examples (I don't know these folks, they just have helpful pictures/listings of kinds of things that exist) If you can't do this, you do need to panel or curtain the ceiling or…

I tig. wear a helmet and have to buy argon every year. this seems like a huge hassle in comparison. is there that big a difference in quality and or range of processes that make it worth it?

Re: How I got my laser eye injury

#135
Having started out my tech career as an intern in an industrial laser lab, this story is parts amusing and horrifying. Brought back a lot of memories of all the ablation tests and via drilling I used to do, with varying degrees of success, to help sell this massive lasers.

Re: How I got my laser eye injury

#136

I worked in a laser lab for a few months early in my career. After the safety training I fear lasers getting near my eyes in situations most people don't care about. I even look away from barcode scanners at grocery stores. Sometimes I wonder about lidar being shot in all directions from those self-driving cars around SF.

There's been at least one sketchy self driving startup that drove their LiDAR hard enough they burnt holes in journalists' camera sensors at CES.

https://arstechnica.com/cars/2019/01/man-says-ces-lidars-las...

Re: How I got my laser eye injury

#137
post #55
post #3

I’m not saying it didn’t happen as described, but this really kinda reads like the “Bald eagle named Albert Einstein flew into the classroom” copypasta…

Yeah, the story contains some obvious bullshit. There is no way in hell a flashlamp-pumped Nd:YAG laser could cut through a piece of steel. With typical ~Hz repetition rate and ~J pulse energy, the average power is only around 1 W. This is three to five orders of magnitude lower than typical welding lasers. This could burn some paint or engrave metal, but burning through a wheel well and brake line is completely ridi…

He didn't claim it cut through steel, JGCs have polymer wheel wells and brake lines like most modern cars.

Re: How I got my laser eye injury

#138

Safety guys always ruin the fun. I was in the Marine Corps and every time we got to test some new piece of gear the safety officer was like "No, you can't live fire it off the flight deck of the ship" or "No, not here, that village is down wind of the dust you will kick up when it goes off." No, that has a kill distance of 6 miles, you have to fire it into a hill." Blah, blah, blah. So after I got out I joined the Na…

I am reminded of the "Sir Isaac Newton is the deadliest son of a bitch in space" speech from Mass Effect 2. https://youtu.be/hLpgxry542M?feature=shared

Compton is a bitch for astronauts too.

Re: How I got my laser eye injury

#139

Safety guys always ruin the fun. I was in the Marine Corps and every time we got to test some new piece of gear the safety officer was like "No, you can't live fire it off the flight deck of the ship" or "No, not here, that village is down wind of the dust you will kick up when it goes off." No, that has a kill distance of 6 miles, you have to fire it into a hill." Blah, blah, blah. So after I got out I joined the Na…

> I was in the Marine Corps and every time we got to test some new piece of gear the safety officer was like "No, you can't live fire...

I thought the whole point of the Marines was to cause maximal amounts of damage. Are you implying there is a constraint on that?

But now I understand why the marines hate the navy: I had a buddy who'd been in the navy and he said they kept the kids busy by cleaning and painting everything but frequently they'd let 'em blow off steam by tossing cardboard boxes and stuff off the end the flight deck and shooting at them with the 50 cal machine guns.

We were good friends, attended MIT together, but if I thought the Navy would take many people like him I'd doubt their ability to fight a war. He was only in the navy because it would pay for school and AFAIK he managed to avoid getting any rank advancement at all. MIT requires, or used to, a lot of all nighters and he once said "I'm probably only sane with these all nighters because I did so much extra sleeping in the navy"

Re: How I got my laser eye injury

#140
post #94
post #44

Earlier quoted context omitted.

> custom infrared -> green laser Nd:YAG lasers always creep me out. I worked in a lab that had an Nd:YAG with two janky doublers: 1064 -> 532 -> 266 nm. The output energy was supposed to be a few mJ (IIRC), but it was basically zero. So the students operating it took off the second doubler and fired it at a bookend. Nothing (well, nothing visible). Took off the first doubler. After investigation, the zapping sound wa…

Replying to myself: I just searched Amazon. There are plenty of green “diode” lasers, 532nm, ~100mW, for very little money. I don’t believe that for a second — those are surely crappy frequency doubled Nd:YAG lasers, probably unfiltered (that filter wouldn’t be cheap, and it might fail anyway under that ridiculous power level), and they will blind you when some funny reflection of the, I dunno, 500mW of stray IR ligh…

I have a friend with multiple green and red lasers, some from aliexpress.

Years ago when the hype wasnt really there he visited me and wanted to show off. I have 3 dogs and I really like this kind of tech but I forbid it to turn that thing on near me, especially in my flat. Even if they are directed away, the chance of unpredictable reflections is just too high for a bit of fun.

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