After [Ross] from FauxHammer miniature model fame got lured into reviewing laser engravers and similar via the Bambu Lab H2D’s laser module, he found himself getting slightly nervous about the whole ‘safety’ aspect of these lasers. After all, lasers can not only light stuff on fire, but it’s a well-known fact that even reflected laser light can be sufficient to cause permanent damage to your retinas. Or worse.
Since your eyes generally do not regenerate, it makes sense to get caught up on laser safety before turning on one of those plentiful-and-increasingly-affordable home laser systems for engraving and/or cutting.
While the issue of stuff catching on fire is readily solved by having a good CO2 extinguisher – and plan B options – at the ready, for safety glasses it’s significantly more complex. There’s not just the issue of finding glasses that block the wavelength of the laser system that you are using, but also with the right optical density (OD) rating. Every mm of the safety lens material can attenuate a certain amount of laser light at the given wavelength, so the OD rating of your laser safety goggles need to match the laser’s power output level, or you might be living with a false sense of security.
Finally, there is the issue of the smoke and fumes produced by these lasers as they obliterate the target material. Much of what is in this smoke you do not want to breathe in, even ignoring long-term dust and VOC exposure issues, so having a solid fume extraction setup and PPE as necessary are absolute necessities. As [Ross] puts it, you don’t want to breathe in the smell of regret today, for your future self to reflect on a decade from now.
Work safe, work smart, don’t become the subject of a laser safety PSA.
The lack of knowledge of laser safety by the general public is staggering.
I ran across someone with an open-frame laser engraver operating it out in the open at a booth in a local mall. There were people standing around it watching the guy engrave jewelry trinkets.
It was one of the MOPAR fiber ones. 40-50w. It’s not even legal to sell those without an enclosure here, let alone operate it outside an enclosed space. But you can get them shipped cheaply from overseas…
I got into an argument with the guy when he didn’t want to hear about “safety garbage”. And he called security when I started telling the customers that he was literally blinding their kids who were like 2 feet from the machine.
I called the mall admin and they told me it wasn’t a problem.
I called the local police and they said there was nothing they could do.
The people I talked to clearly had no idea of how dangerous these things can be when operated wrong.
I called the state police, even though I didn’t think they could do anything, but the desk sergeant knew EXACTLY what I was talking about and immediately had her captain call the local chief to explain the situation.
The stall was empty the next time I was there.
According to a clerk, the guy was only there for 2 days total.
I hope he didn’t cause too much damage, but at least it didn’t make national news by blinding dozens of kids.
On the one hand, it is AWESOME that I can go buy a useful laser for under a grand nowadays.
On the other hand, it is TERRIFYING that any ignorant rando can do the same thing, and no one will realize there is a problem until a bunch of people get hurt.
Also, it is incredibly frustrating to see someone doing something dangerous and illegal like this, and have no way to stop it because everyone is ignorant to the danger.
If that state cop hadn’t HAPPENED to know exactly why it was a problem AND hadn’t gone out of their way to fix it, what then?
Call some news shop and see it they want to bite on a story?
Try to get in touch with a critically underfunded/gutted federal safety agency?
Hope the guy blinds himself before he blinds too many kids?
Vigilante?
What then?
I agree. I bought an enclosed machine from a reputable manufacturer. I probably expressed too much concern to two friends who bought open frame lasers, but they actually built enclosures before running them, which I was relieved about.
One of the very first mods I did to my K40 (after I’d sorted out all the electrical safety issues) were safety interlocks on the lid and an extra, thick sheet of polycarbonate on the window, it’s scary to think anyone can buy these things without any idea of the safety issues
Adding interlocks is a good idea, but the plastic window in them is fine. What did you do, install the laser head upside down?
no a mirroring surface under an angle is enough. way easier to do than to completely rebuild the projection head.
Polycarbonate (Lexan) is good for mechanical protection, not so much for blocking the laser light. Plexiglass (acrylic, PMMA) absorbs CO2 light much better: essentially total extinction in 0.1 mm.
Whatever you do, don’t use polyethylene: it’s basically transparent to CO2 light.
I’m in the process of replacing a window on the console laser at the local middle school.
Rabbit Laser, the original manufacturer of the machine, told me with no uncertain words that the window should be made of acrylic, and that it’s cheaper to use a local source rather than ordering one from them.
I thought the top window was polycarbonate as well, until recently.
As far as beam safety, once it leaves the focusing lens it focuses to a point and then expands. if you try to laser a mirror or something, by the time the beam goes more than 4 inches beyond the focal point it’s already expanded and generally safe.
That’s for CO2 laser cutters. My understanding is that the fiber laser beams are tiny and don’t expand all that much.
Can anyone fact check that last statement?
Ah, yes, good point. Acrylic is specifically very good against the 10 micron CO2 wavelength, and their usual divergence means they are unconditionally safe beyond a meter or so even without the plastic absorber, because the 10 micron wavelength also doesn’t get through your cornea to get focused on the retina.
A very important EXCEPTION is when doing mirror alignment: the power density in the collimated 10 um CO2 beam will happily give you permanent scars very quickly.
But a fiber laser is a completely different beast. Pretty much any common transparent plastic will be useless for blocking the light from 1-micron fiber lasers, the beam does not diverge nearly as much, and enough energy can get through your cornea and lens to do retinal damage without you even noticing.
If you can’t enclose a fiber laser completely, with interlocks, then you MUST use goggles specifically rated for the wavelength of laser you are using. Be prepared to spend $200 or more for quality glasses with a trustable pedigree.
While the enclosed machine is a really good idea when its a production machine, or for use by the ignorant I have no objection to machines being used without for the folks like the HAD audience who should understand and treat it with the respect deserved – no enclosure opens up extra possibilities in how you use them, so in your personal home lab or other controlled condition so properly controlled it is fine. The important bit is being sure they are aware of the level of danger posed – building your own enclosure sounds good an all, but if the laser you are using will burn right through it its probably actively more dangerous as you will think its safe etc.
Lasers are very similar problem to the arc welders really, you need to pay attention to the safety of those around you as well as you own, and I really wish there was a greater awareness of that with how dangerous to innocent bystanders it can be so mandate something other than just the little yellow ‘I’m a dangerous laser’ triangle that is put on everything including stuff that is basically eye safe – when the only danger marker ever used is shared across such a wide range it just makes it easy to fall into the trap of thinking they are all as dangerous as each other, even if you are relatively well educated.
Well done on finding someone to take you seriously. I’m surprised that mall admin didn’t listen to “This laser is going to blind someone and poison others who will all sue you”
When dealing with uninterested authorities, you have to frame your problem in a way that will affect them. Personally.
A local tree was rubbing along the power lines and throwing the occasional spark (and the wood was hot and burning). I suggested that the police officer block off the road in case the powerline wire snapped and came down on someone’s car. He refused, saying essentially that it’s his decision and her didn’t think it would be a problem.
I looked at his name tag and said “Officer Marshall decided not to block off the street at 1:30 PM. Good enough for me.” and walked off. Ten minutes later we had cones blocking off the area.
When reporting this problem, get the name of the mall admin, and say “John Jones authorized the merchant to use an unshielded laser out in public. Good enough for me, I’ll make a note of that.” It puts the hint of fear in his decision, he’ll probably ask around about the dangers, and then do something about it.
This, by the way, is a standard sales technique. You can’t just say “would you like to by a photocopy machine”, you have to say something like “a photocopy machine will reduce your costs by $500 a month” or similar.
It’s how you get peoples’ attention.
A call to the local TV news station is likely the best bet for quick action. Have other examples of items that are illegal, toxic, potentially highly dangerous, etc., yet can be purchased with a click and a CC number. Need a catchy title: “Dangerous or Illegal Items; Buy With Just A Click”. If possible, have a rough first draft at hand for the story; would be a big plus.
As a maker I’ve used many different lasers, where my most used is a home build CO2 at hackerspace Bitlair. Designing bits to then have the machine cut them out remains magical. For my work I also use diode/fiber/dpss lasers. These live in a laser safety enclosure, and you can’t turn them on without closing the box. The laser then does its thing for weeks on end.
The laxness on safety is quite curious to me, and discussional always leave people annoyed. They don’t want to be pointed out that the stuff they laser is actually toxic for them and destroys the machine. ‘The laser cuts it, therefore it is allowed’, is not too uncommon as an answer, sadly.
As for content, I would have preferred a link to the text based source he has the information from. For example, a list of materials and their fumes would be nice to have for future reference. Looking at all his screenshots with text, while it may not be wrong, it still may all chatGPT.
Similar to using abrasives on your lathe etc – not best practice but if it works it works. The machine isn’t these days expected to last decade after decade so damage to it isn’t a big deal it seems, so cheap just get a new one! Though dealing with the cutting gas and particles so you don’t breath them certainly should be.
Maybe I can agree, if it is your own machine. But a large format laser cutter is a significant investment for a hackerspace, and no-one is looking forward to rebuilding it. Furthermore, the same nasty fumes are also the corrosive ones.
Yeah that is a good point if it isn’t your machine you better be treating it properly, including following any rules the owners put on, even when they are not really defensible.
Leave it to Bambu, who makes printers that are very difficult to service or repair, to put a laser inside of one that’s going to gunk up the insides with fumes and residue.
Maybe with tdi minimus removed from law, these won’t sneak through as easily and customs will actually stop the unshielded ones from getting into the hands of makers who are going to lose their eyesight.
Don’t get me started on people who think it’s perfectly okay to slap one on their CNC router and run it open.
Well that can be perfectly OK, even required to actually be able to do the tasks you do as any enclosure limits the maximum object size you can work on – its all about how you do it. Though obviously an enclosure with decent lockouts so you can’t run it open is safer and idiot proofs the machine a fair bit it isn’t required to operate the tool safely – all that is required to operate a laser in the open safely is control of the space, actually very similar problem to arc welding – keep everyone else away, and have nothing that burns too easily in the danger zone.
“While the issue of stuff catching on fire is readily solved by having a good CO2 extinguisher – and plan B options – at the ready, for safety glasses it’s significantly more complex.” Whenver I use anything that generates heat (welder, cutting torches, ETC.) I use a water fire extinguisher because it gets the heat out fast. Just my two cents.
” having a good CO2 extinguisher ”
CO2 extinguishers are great, but I can buy five dry-powder extinguishers for the price of a single CO2 one, and I don’t have to treat them like the hazardous container a CO2 is.
Mine are located near the risky equipment and along the exit routes.
Sure, the powder will make a huge mess when they get fired off, and that might be disincentive to use them when needed, but that’s a price I’m willing to accept.
Ski goggles look cool and you can’t change my mind. Those are the kind of goggles you wear when doing dangerous activities, so it’s cool by association.
Ski goggles are cool, but, if you want to hang with the really cool kids you have to do the safety squint. Just close your eyes enough to barely see what your doing;) /s
Packing tape’s only downside is taking off your eyebrows.
Best comment on the internet this morning.