So I laser weld, and beyond my own PPE, interlocks (gun won't fire if it's not touching metal, etc), the most important part of the whole setup is laser safety curtains.
Because it's a 2500 watt laser, if i didn't have laser safety curtains , the relections/etc could very easily blind someone at a fairly long distance.
The NOHD (nominal ocular hazard distance) is something like 10km (2500 watt laser, 0.06mm spot size, divergence is very very small). The actual hazard distance is shorter, but still, kinda crazy.
(as for why i have a laser welder - i got it cheap and besides the downsides above, it is very easy to weld ~anything without much skill. A person who has never welded in their life can weld sheet metal and have it come out basically perfect in 5 minutes)
Why don't welding/cutting lasers add more divergence with built-in optics? Would it hurt performance? It seems like you could add 1 mrad and it would hardly make a difference at the usual working distance, but spread out to a meter over 1 km, so you can't zap people across town.
If it's a 1-micron wavelength laser with a 60 micron radius spot, the divergence can't be much less than about 5.7 mrad half angle. What makes eye safety tricky is just that 2.5 million milliwatts is a lot of power. Even when you spread it out some.
‹twitches in metric prefix›
2.5 kilowatts. It's called 2.5 kilowatts.
‹calms down›
2.5 kilowatts is how much power a tea kettle in the UK draws. It's an insane amount of power to pump into a 60 micron point.
This seemed like a wild claim (2500 watts for a tea kettle!? As much as a microwave oven in full blast?) so I looked it up. Wow.
It's actually only americans who unaccountably make do with these horribly underpowered kettles. The rest of the world wants their tea and they want it now...
Technology Connections did an excellent video on this: https://www.youtube.com/watch?v=_yMMTVVJI4c
tl;dw -- kettles in the U.S. only take about 4+ minutes to boil a liter of water. So when you say "now" you really mean it.
I live in the US and have an induction stovetop. It can dump 3600 watts of targeted heat into a pot of water. It can boil 2 liters of water in ~3-5 minutes.
Plus, when you reduce the heat the heat reduces almost immediately.
Nothing else compares with the speed it works that I've ever used before. Definitely worth the upgrade in time saved at the stove.
I just nuke a mug of water for a minute or two when I'm making instant coffee. I never understood the big deal about electric kettles.
A water kettle lets you consistently heat water to the same temperature (not just boiling, high-end kettles have additional temperature options), regardless of:
- Amount of water
- Initial temperature of water
- Position of water container
They also prevent superheated water accidents.
Yes and: Kettles are much easier to clean than microwave (interiors).
Well our kettle is 2.4kW, our microwave is 800W or so effectively. Also our induction stovetop is much faster, so the nuking option is slowest by a lot.
Boiling water in a microwave does not make the microwave dirtier.
In fact if it boils it can help clean it!
True. The mess comes from a son reheating food, often tomato sauce based, without a lid.
most lid are plastics, so i suggest people heating without lids. Cleaning mwave is east anyway. I am sure ppl don't want microplastic laden food.
Better that than reheating it in a kettle!
Microwaving has the undesirable side-effect of also heating the exterior of your beverage's vessel.
Electric kettles make it easy to pour for pour over.
When the other options just need to be poured, waiting 4.5 minutes for boiling alone is a significant waste of time.
You can improve that by using less water, but I would still like to double the power.
Interesting what power do microwaves in US deliver. In EU the regular micros are about 900W range give or take 200W (that is 1500W from wall because microwaves are not efficient machines) but kettles have usually range 2200..3000. So it is obvious why everyone uses kettles. I myselft have 3kW one and it heats 0.35 litres to boiling in 51 seconds. To have similar microwave it would have to be 3000W micro that is 4500W from wall and have not seen that kind of monsters, also regular 1 phase EU socket delivers max 3600W so that limits it also.
A typical US microwave draws 900-1100 watts too. I can't even find a 2000-watt microwave listed for sale in the usual consumer places. That'd be like a "pro chef" level luxury item, likely needing beefier electrical wiring and so on. US electric code requires a dedicated 20-amp circuit for microwave, which isn't supposed to serve a 2000-watt load.
> it is obvious why everyone uses kettles. I myselft have 3kW one and it heats 0.35 litres to boiling in 51 seconds.
Wh? It’s definitely less hassle, and maybe faster, to fill a cup/mug and stick that in the microwave
Than it is to fill a cup, pour that into the kettle, boil it, then pour it back in the cup. Or you have to put more water into the kettle than you need, because you can’t measure it accurateLet, and then it takes longer to boil
Standard wall outlet in the US is 15 amps, so a maximum of 1800 watts. 20 amp outlets (which can supply 2400 watts) are getting common, but I've seen very few home appliances that actually use the extra amperage (as determined by having a plug keyed for such an outlet).
The back of the envelope comparison isn't difficult. The energy in different forms are doing the same thing.
Doesn't your microwave heat a cup of water in about the same amount of time as a tea kettle? And most tea kettles are bigger than one cup.
Now, think about concentrating the same amount of energy to heat up your eyeball. Or worse, concentrated into a tiny point on your eyeball.
Brits don’t mess around with tea I guess. I believe they’re mostly on 240v even for residential there. Correct me if I’m wrong but I don’t think it would even be possible to heat water that fast in the US on 120v.
Correct, it takes about twice as long to boil a kettle in the US. But the US is the anomaly here. Most countries use 220-240V mains like Britain [1].
[1] https://en.wikipedia.org/wiki/Mains_electricity_by_country#T...
British outlets are individually fused so they're typically rated for more current
British outlets are fused for _lower_ current than american outlets, not more: 13 amps instead of the 15 or 20 that's common here. It's the voltage that's higher, which means that the power transferred for a given current is about double.
Fused for 13A running off 32A ring main.
Continental Europe uses 16A radial circuits so the current rating is higher there.
EDIT: Of course, you can't run two kettles on one radial, but you can on one ring.
Technically, the US does as well.
You have 240 V at the panel, but you only run half for each common circuit.
Technically basically all buildings in Germany (residential and commercial) run on 400V 3 phase power. But access to it via sockets is only common in residential homes via sockets in a garage. It gets more common with car charging although they rather use 3 x 230V as far as I am aware of.
Fun fact: 400V 3-phase and 3x 230V are the very same thing. You'll get 230V AC between Neutral and each of the three phases, but the AC voltage between two of the phases will actually be 400V.
I'm living in apartment block built in 2016 in eastern EU and here every apartment has a separate 3 phase(5 pin) socket for the stove. It is a 7kw beast, it can easily destroy regular aluminum-steel pan if you put it on max heat. Steel part will fall apart.
Same in Eastern Germany, at least up to the 2000s. (Probably still, but I left, so can't vouch.)
I seem to remember our electrical stove and oven back in Germany in the 2000s using three-phase power.
Here in Singapore I think our pool pump uses three phase power, too. (Our plugs and outlets here in Singapore follow the British model.)
They have a man watch the telly to hit the button to turn on the power for all the teapots going on. https://www.youtube.com/watch?v=slDAvewWfrA
That poor operator probably gets an adrenaline rush (and finger twitch) every time he hears the Eastenders theme tune.
Assuming perfect energy transfer (fairly reasonable for conductive heating of water) with no losses to ambient, a starting temperature of 20 C, 1 L of water (which I assume to weigh 1 kg) and a 1800W kettle (the max you’ll find in America): no.
t = specific heat capacity of water * mass of water * degC deltaT / power
4.186 J/gC 1000g * 80C / 1800 J/s ~= 186 seconds
Higher, that would be quite an extraordinary microwave (probably too high) - 800W to 1kW at maximum typically.
(I use mine mostly on the 90W or 180W settings, for defrosting.)
I recently bought a 3500 watt electric kettle out of the bargain bin in LIDL, for around 20 euros. Europeans do not mess around when it comes to hot beverages
Yeah funny, i was going to say 2.5 kW kettles are a britishism and the ones on continental europe are weaker...
... but then i checked my eastern european kettle and guess what, it's ... 2.4 kW.
> This seemed like a wild claim (2500 watts for a tea kettle!? As much as a microwave oven in full blast?) so I looked it up. Wow.
Almost all household appliances that heat (and specifically heat food or water) will operate at the limit of what your house can supply.
So that's about 1800 Watt in the US and about 3500 Watt in most of the rest of the world.
It's only natural that you see almost any (heating) appliance cluster around these numbers.
(I'm actually not quite sure where you would see 2500 Watt kettles. Perhaps some are deliberately neutered a bit, so that you don't blow a fuse in case you have anything else on that circuit?
Keep in mind that in the UK, but not in eg France or Germany, every plug also has its own fuse.)
I found it odd that in the US most home brewers don't use electric, but as you say they are limited by the elements they can use.
Here in the UK, my home brew beer set up has a 3000w option - great for boiling 25 litres of water/wort - that said it came with a EU plug with some sort of 'fancy' UK plug convertor. After about 4 years the plug started to get so hot that it melted a socket or two - I found that inside the convertor the connection between the EU plug and the UK was really thin, which was causing it to heat up.
I cut off the end of the cable and rewired it to a heavy duty UK plug - it has been perfect since then - and no longer over heats.
Electric is growing in popularity. It’s not overly expensive (compared to the cost of the gear, anyway) to get a dedicated 30A or 50A 240V circuit installed; or you can brew next to your washer/dryer, since there is nearly always a 240V circuit available there.
> I found it odd that in the US most home brewers don't use electric, but as you say they are limited by the elements they can use.
Yes, but you still see electric space heaters. And they essentially all also have the same wattage: the limit of what they can get.
british household AC is wild, it's like they've got a full-power american range plug for every outlet
Not just UK, the whole world except North America and Japan.
South african plugs are rated 16A @240V. Thats a safe 3.5kW at each and every plug socket in the house.
> Not just UK, the whole world except North America and Japan.
Brazil is also an exception. The standard socket is only 10A (with a 20A alternative for things like air conditioners), and the voltages vary depending on the city (and the building, and location within the building); you might have 110V, 115V, 127V, 220V, 230V, and perhaps others I have missed (I went in more detail about it at https://news.ycombinator.com/item?id=40385851). I live in a 127V/220V area, so my single-phase sockets are 10A @ 127V, for a total of only 1.3kW each.
So it's pretty normal for a "230v" plug to actually be anything between 220v and 240v. Voltages fluctuated pretty wide depending on location. It's all down to the loca transformers.
But mixing 100s of volts with 200s of volts sounds mad. I presume you had the special plug for your 200 range outlets? Does Brazil also have split phase AC like the US?
> I presume you had the special plug for your 200 range outlets?
The same type of socket is used for "110V" (usually 127V) and "220V", sometimes in the same building, sometimes right next to each other. The "220V" socket might be colored red, or might have a sticker saying "220V" glued next to it, but don't count on it. The only difference is between the 10A and the 20A, the pins on the 20A plug are slightly thicker and don't fit in the 10A socket (the opposite works fine).
But at least, it's better than a couple of decades ago: on top of all that, back then we didn't even have a plug and socket standard. It was a mix of several types, including a "universal" socket which looked like the common USA socket but could also accept plugs with round pins, and all of them (including the USA standard sockets) could be used for both "110V" and "220V". The new plug and socket standard is great; it's better than the USA standard, since a partially pushed plug won't expose live pins (and it's also slightly smaller, allowing for denser power strips). It's unfortunate that they didn't also modify the European standard they used as a base to add keying for the different voltages (while allowing a universal plug for things which can work on both voltages), but I understand that trying to do too much could make it politically unfeasible to mandate the new standard.
> Does Brazil also have split phase AC like the US?
It's more common to have three-phase AC (that is, between phase and neutral is 127V and between a pair of phases is 220V), but we also have some places with split phase (for instance, 110V between phase and neutral and 220V between a pair of phases).
I remember watching a Technology Connections video where he was looking at space heaters rated for small/medium/large rooms and pointing out that the medium/large room heaters were both 1500kW (iirc) as it’s the maximum continuous draw from a US socket.
Over here in NZ we get pretty similar ratings on the same style heaters, but the large room ones are 2400kW because we can get that from any socket.
Also with my hobby - sewing. A lot of people in North America talk about forgetting they left the iron on, but I switch it on and off every time because it heats up in 30 seconds - less if it’s been on recently.
And because nearly every single house in UK is wired for single phase only, your connection to the grid is usually rated at 80-100amps(so a regular British home can draw around ~20kW on a single phase).
And just like Americans have special access to 'full-power', there's special access to three phase 400 V in many nominally 230V countries, too.
That's eg common for electric stoves in your kitchen.
When we discuss laser power, damage begins in the milliwatts range, so those of us in the hobby prefer to state it like that so we can easily give people an idea of how fucked they can be if they treat a laser like a toy.
2.5 billion microwatts.
Sure but how many millijoules per day is that?
216 billion.
<twitches in metric prefix>
60 micrometres. "micron" is a deprecated irregular word that is unlike every other scaling of the metre.
Listen, our shoe sizes are measured in barleycorns, so we’re doing the best we can to adopt metric in places.
Correct me if I'm wrong "micron" IS metric (decimal based system) but it's NOT an SI unit?
Eh. At least this one is just a name. I don't know how precise we have to be in a blog post, you know? They're the exact same unit.
On the other hand, 2.5kW of light is not outrageous. It’s not drastically higher than some of the larger theatrical lights. (Not that being in a spotlight is pleasant, but it does not permanently blind the actors.)
A lot of this comes down to wavelength. Some wavelengths get focused by one’s eye and can concentrate their power in a small spot on the retina. Other wavelengths will be absorbed before they get to the retina and will therefore deposit their power over a larger area and in less sensitive tissue.
It can also make a difference if the light is pulsed.
Are you sure that's actually 2.5kW of optical power? Non-scientific lights aren't usually rated by optical power, but by electrical power.
But isn't stage light labeled for consumed power, not emitted power?
that's what i was going to say. and while you can use barn doors and lenses to hone the throw (the size of the beam on stage) -- it's not collimated like a laser is. even with parabolic reflectors like par cans. we're talking magnifying glass and the energy at the focal point (minus what the air absorbs for a given wavelength etc)
I'm not an expert here. But according to https://en.wikipedia.org/wiki/Diffraction-limited_system (see last paragraph of the intro) the diameter of a laser beam doesn't impose a diffraction limit on the optics it goes through. You still get the angular resolution you'd expect given the entire aperture of the lens even though the beam is only going through a small area of it.
Whatever refracts the light will have to stand up to the beam for long periods of time. Maybe it's a materials science problem.
As long as it doesn't absorb the light, it's fine.
Just like the electric cables for your water kettle typically don't get hot.
Your kettle's power cable is sized to handle the relatively tiny current put into it, but even then it does warm up slightly. Try to run a million amps through it, and it will vaporize.
This type of laser carries so much energy that even a tiny fraction of a percent absorption will add up quickly, hence the propensity for injury.
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 use laser absorption coating or other things.
There are places that also just use reflection sensors that detect reflection on the ceiling and trigger (again, machines already support handling this). I have heard this works very well but have no direct experience with it.
All that said, reflection off ceiling is more uncommon for practical reasons (The angle at which you hold the gun to the piece, the fact that ceiling directed angles often become back reflection into the gun which it already detects, etc).
They already detect very high reflection as well.
For a makerspace, one of the issues you will have is that people will likely want to try to weld copper and aluminum a lot, both of which are highly IR reflective.
If you said "You can only weld steel and iron" you would eliminate a very high percent of reflection in the first place.
Here's a basic chart that looks right: https://www.researchgate.net/profile/Tomasz-Kurzynowski/publ...
For a 1064nm laser, you can see Al or Cu is going to reflect a lot of the energy, while steel/iron are still off the graph high in absorption
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?
I know one of the reasons we wanted pico-second and shorter pulsed lasers is that they can cut material with little to no damage of the neighboring material. There was a demo that I read about when this was all brand spanking new research, where they claimed that a laser scalpel causes no heat damage to tissue outside of a cell’s breadth from the contact point.
Here's a figure comparing the hole left in a metal surface with normal and femto-second pulses. The difference is quite stark.
https://www.researchgate.net/figure/SEM-image-of-the-substra...
Is it this?
https://en.wikipedia.org/wiki/Coulomb_explosion
It's related, but as i recall the reason that short pulses cut better has to do with heat transfer. Most heat transfer in metal is due to the vibration in the electrons, being much lighter than the atomic lattice they move in. Very short pulses, means that the heating in the beam path happens faster, than the electrons can transfer it out to the rest of the metal. In long pulses once the metal is vaporised, a lot of the surrounding material has melted. This molten metal cools into jagged structures and that leaves the edge weird. All this doesn't happen if the pulse is short enough. It vaporises metal before the surrounding structure has a chance to heat up.
Here's a figure showing the quite stark difference. https://www.researchgate.net/figure/SEM-image-of-the-substra...
Awesome, those photos do illustrate the difference really well.
Thanks heaps. :)
That's how LASIC and PRK work, after all!
its the operator skill part when dealing with thin sheet metal. It just works better / easier / faster for thin stuff, where in TIG, that's the high-skill work that everyone pays big bucks for.
Agree with the post above, though. The safety setup for lasers is basically full isolation.
seems like its more cost effective to just stay on or above 20ga unless you're really high volume or you really need the weight savings
> completely enclosed separate room for it with door interlocks
You absolutely, absolutely need this. Do not take chances. "Real estate is expensive" is not an excuse for a blinding hazard to members and visitors of your space.
I've worked with very high powered room-sized laser cutters before and they should all have a full room enclosure.
Are lasers typically able to reflect off of surfaces that diffuse light (ie drywall)? I’m totally ignorant when it comes to laser safety, apologies if this is a stupid question .
Do you see a bright spot when aiming the laser at drywall? If the answer is yes, then laser light is being reflected into your eye.
Hope this helps!
> Do you see a bright spot when aiming the laser at drywall?
It was red for a second but now what appears to be a black hole is consuming everything.
Congratulations, you've made your eyes laser-proof then! From now on, you can safely look at high-powered lasers.
This subthread is perfect for training AIs. Google, found it yet?
It's not that simple. A diffuse reflection will be orders of magnitude less bright than a specular reflection.
For a very wide range of laser powers (not 2.5kW), the trouble is in guaranteeing a diffuse reflection.
I’m confused. This is true from every angle from which you look at the wall right? So there has to be quadratically less reflection than e.g. a mirror, but still a lot more then a completely black surface.
The inverse squared falloff from a diffuse surface is not enough to prevent eye damage if you're in a regular-sized room, and playing with a class IV laser, or even some class IIIb lasers (depending on the distance, and the duration).
Got it, thanks!
Surfaces may produce diffuse or direct reflections (or more commonly, a mixture of both) for any light source. If you can see it, it's being reflected.
And even if you can't see it. You won't see a spot from an IR laser while it's burning the hell out of your retina. Which is why many (but not all) IR lasers co-produce a visible spot so you can see where the dangerous beam is.
>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.
That is the only way to not blind your membership.
What I do to match my lazer curtains is I hang a lazer tapestry off the ceiling to block all the lazers. I don't do lazer welding but I have lazer scissors and lazer axe which it is still useful for
Separate room with interlocking doors
-coming from another hacker space
NOHD = Nominal Ocular Hazard Distance
Yes. Sorry for not expanding it. I edited it to expand it.
For others:
The NOHD is really a nominal distance. It's just the distance at which the beam falls below the maximum permissible exposure.
The 50% eye hazard distance (ED50) is 31.6% of this number. That is, if the NOHD is 100m, then at 31.6 meters you have a 50% chance of causing a medically detectable change to the eye. It's also worth noting - the beam power at this 31.6% distance is 10x, not 3x, what it is at the NOHD.
For laser welding, the spot beam is small (60um) which is one reason the NOHD distance is so high.
For reference, a laser pointer is like 1.5mm, so this is 25x smaller.
It also doesn't help that the lasers used are all ~1060-1070nm wavelength and so invisible as well :)
I'm dying of curiosity how cheap a cheap laser welder can be.
So, to clarify - what i have is a very nice IPG lightweld 1500 XR. They are normally not cheap (30k), and are very nice and well thought out safety wise.
One of the fun parts when i lived in the bay area was that as companies got acquired, they didn't know what to do with the stuff they had before acquisition that isn't needed anymore, and it either sits in a warehouse, or gets auctioned off (or both!)
So for example, at one point, Google (after acquiring terra bella and some other companies) had like 5 or 6 very nice 5 axis VMC's sitting around collecting dust. Each was worth well over 250k. They already had plenty of VMC's in the machine shop, etc, and didn't need these, and it was not worth the trouble to sell them. At least back then.
In my case, I was able to get this welder for way less than half price.
The lightweld's have come down in price over the years, and that will keep happening.
They are pretty much the most expensive laser welders though, you can easily get one for 10k these days.
The truth is, however, if you go cheaper than this, what often what gets overlooked is safety. So some of them in the lowest price range don't even require you touch the gun to metal before letting you fire, etc.
All of them can weld the same, so if you go looking, look at other things too.
THe other thing - one of the nice things about laser welding is that it's improving very fast. So similar to fiber, running multiple types of lasers or optics in the cable is not particularly more difficult than running one. They just add more fibers (it's not quite the only issue, but you get the point).
Why does this matter? Because it means you can run another laser or something to monitor the weld and adjust parameters on the fly. Which lightweld and others are starting to do. So if you are moving the gun too fast/slowly, or got the power wrong or whatever, it will compensate automatically
This probably won't ever happen on mig/tig. The lasers are heavily computer controlled already, this just adds a feedback loop.
It also enables real time certification of a weld - see https://www.ipgphotonics.com/products/laser-weld-measurement for an example (this is a separate product, but you get the idea)
In any case, my take would be - if you want to play with them as a hobbyist, or have too much money, they are cool Otherwise i'd wait ~5 years and what you get will probably be 5-10x better for the same price.
VMC == Vertical Machining Center
PSWAATY == Please Say What the Acronyms Are. Thank You.
> PSWAATY
I'm keeping that one.
Usually i do, but there is one acronym in the entire 450 words, and it doesn't really matter to the point what the thing was?
If the definition doesn't matter, better to use a more generic term than a more specific/cryptic one.
OK. Thanks for the informative post. Don't want to discourage you from more.
I agree with you.
It's also pretty easy to figure out what you're talking about from context.
It's the second post in which he did this. And how should anyone know whether it's important to know what it means without knowing what it means?
I'm of the opinion that the guy or gal is giving us valuable information so let him rip instead of asking him to change stuff. If we can't google a simple acronym with the right context which we already know, we're on the wrong site.
> plenty of VMC's in the machine shop
So now I have to know why Google has a machine shop. Beyond the obvious "why not?"
They make hardware prototypes. When you do that having your own machine shop can lower the iteration time and thus speed up the development.
Just from the top of my head: waymo develops their own lidars, akamai obviously needed a ton of machining for the kite, project loon probably had machined components. And those are just the flashy examples we heard about outside of the company. They can have ton of other projects which didn’t get to the point where we heard about them but required hardware prototyping.
Duh! Of course!
I think Google and I only think search/ads. I forgot Alphabet has all that other stuff going on.
So does Alphabet.
All other projects are on the cancellation list, so don't worry overmuch about them.
IIRC it was started in earnest for Nexus phone prototypes in the early 2010s.
We had one at the Facebook offices too, as a side-effect of the Oculus acquisition. Hardware prototyping is fun
Google as a company manufactures hardware, it makes sense to have a machine shop for prototypes.
Google was founded by burners who want to take cool shit to the desert.
They are in the rich people’s glamping camp. They haven’t lifted a finger on the playa, ever.
Google used to indulge employees' interests. They fund, or used to fund, "the generator", a build shop in Reno. I know a Googler who openly worked on a small art project at the office, albeit a small part of the work.
I'm not saying that Google has machine shops purely for burning man. But I strongly suggest that when the idea has been floated in various locations, one recurring theme is "yeah let's! And let's get some lasers and propane burners!", and I also believe that some managers were thinking "great, this is the culture we want."
The register calls it "the chocolate factory" as a reference to Willy Wonka. Shame they descended into evil.
I don’t mean the rank and file but Page and Brin. They’ve only ever gone the glamping sparkle pony route.
> I'm not saying that Google has machine shops purely for burning man. But I strongly suggest that when the idea has been floated in various locations, one recurring theme is "yeah let's! And let's get some lasers and propane burners!", and I also believe that some managers were thinking "great, this is the culture we want."
There was! It was the predecessor to the Garage. I suspect because the machine shop boys wouldn’t let them use the real toys.
Lots of reasons. Prototyping consumer goods of various sorts, etc.
> They already had plenty of VMC's in the machine shop, etc, and didn't need these, and it was not worth the trouble to sell them. At least back then.
Darn, we were trying to get a mill for the NYC office's makerspace. It was probably a safety issue and not a parts procurement issue, though.
I see a bunch of them for about 1k on aliexpress. Any thoughts on those? I realize getting the cheapest possible unit is probably not the safest idea with laser welding.
> So some of them in the lowest price range don't even require you touch the gun to metal before letting you fire, etc.
Are you able to attach them to the heads of sharks?
If you can get them to stay still long enough, maybe.
PSA: Sharks die quickly if you get them still. Their heartbeat is connected to the swimming motion.
Some sharks have to swim to move water over their gills. Not even close to all of them and it's not due to their heartbeat being connected to their swimming.
https://www.britannica.com/story/do-sharks-really-die-if-the...
Thanks. In my defense, I heard this from my diving instructor who is a marine biologist.
It is a thing. It's just not as universal as people try to claim. There's a lot of biology in the marine world. No one can be an expert on all of it.
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 raise enough money to start importing them, I'm sure I could sell quite a few.
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.
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...
Be careful as far as the FAA is concerned drones get the same legal protection as a plane with people in them so messing with them is legally hazardous.
I know. Hence the laser: blind the camera first and they can't prove that it didn't mysteriously drop out of the sky as soon as it passed the property line.
Go get em cowboy!
Oh yes: https://youtu.be/xNmbvaUzC8Q
This is why we can't have nice things
It's rare to have such a clear illustration of the difference between intelligence and wisdom.
There's no way this stuff isn't giving the secret service nightmares.
This guy set ablaze the inside of a vehicle through closed windows from a significant distance.
I had to look it up, because I thought that was what "Reason" was in Snowcrash.
I was mistaken: Reason was a railgun.
The weird part of reason is it is also (in the family of) a mini gun with it's multiple rotating barrels.
I feel obliged to mention that this does feature prominently in Kim Stanley Robinson's Red Mars trilogy. The single most important piece of infrastructure on Mars is a space elevator, but not everyone on the planet is happy with how the owners of the space elevator are running things.
Almost a different Funranium post: https://www.funraniumlabs.com/2022/12/choose-your-own-radiat...
https://www.everlastgenerators.com/catalog/laser-welders this is probably the easiest one to buy from a reputable (non alibaba) company. its $17k, so not "cheap", but hardly expensive.
My gut says they'll be for sale at $2-5k within 2 years at the rate things are going.
A quick search is showing me new machines in the $7k range. You could probably pick up a used one for a few thousand less. This is cheaper than I would have thought, honestly - a decent full MIG rig is not exactly cheap.
They are coming down in price very quickly.
The materials cost is really not very high (no idea on the laser itself, but the rest is easily <1k. Probably <500.). The R&D cost was probably very high to start (but also coming down).
I had a friend, “Kevin” who got picked as a lab assistant for a guy making one of the first violet, and IIRC, picosecond lasers. It’s frickin’ laser beams so of course I had to ask way too many questions. They probably should have been using curtains but if they were he never said, and I’m sure laser safety has evolved with the wattage and commercialization, whereas this was a static benchtop system.
There were lots of mirrors and prisms and they has to calculate refraction off of them and stick carbon blocks everywhere that light transmission was less than 100% efficient so that no light could escape the system except via the target.
What are the curtains made of? I’m surprised 2500W on 0.06mm don’t just go through like there’s no curtains
hopes and seams
Maybe it just diffuses the beam?
Somehow your comment reminds me of Tech Ingredients grilling a burger with laser:
https://www.youtube.com/watch?v=9VmITd0dKAo
Please provide some more details on your laser welder. Did you import it from China? I want one so bad, but buying them in the USA seems to be 4-5x retail cost in China.
I wouldn't get one from China, no matter what the price is. Money can't buy eyesight, not in this case at least
Cheaper ones often skip safety features like interlocks to so be careful.
> (as for why i have a laser welder - i got it cheap
that's how a lot of good stories start
You don't want to hear how I met the ex.
10km … damn. And the biggest problem is, the danger is invisible.