Can you call it a bandsaw if it has neither band nor saw? [WeldingRod1] does, with his entry in the laser contest — a manually-controlled laser cutter that he’s dubbed a Laser Bandsaw. Some might quibble that it’s not actually sawing with the beam, and others will inevitably find the safety implications rather frightening. We think it’s a fun project and that [WeldingRod1] can call it what he wants, as long as he follows his own advice and keeps his laser goggles firmly on his precious vision orbs.
He has actually put some thought into what started as the physical manifestation of a joke in a podcast. The blue diode laser — a NUBM44 diode rated at 7 W — got a custom-made copper heatsink. It’s also got a hefty beam dump in the form of a stack of box knife blades. That’s very necessary to keep the beam from reflecting where it shouldn’t, especially when you consider this operates like a regular band saw: you turn it on, and it’s ready to cut. With only 7 W of laser power it can’t cut that much, mind you, but apparently it’s great on balsa wood and blasts black paint off like nobody’s business.
Now if this was our shop we’d probably want to put the laser diode onto some kind of CNC platform, be it Cartesian or SCARA. But we’ve seen that done many, many times and if you’ve got the motor skills this might be just the tool for you. There’s a pinout and STLs for the 3D printed frame on the project page if you’re interested. If not, why are you still here? The article is finished. Go make something lase and send it in. The deadline for the 2026 Frikkin Laser Contest is fast approaching!
In terms of size, gestalt, and semi-plausible use cases, it seems a lot more akin to a laser scroll saw than a laser band saw.
(as a bonus, the “scroll” part remains just as accurate when it uses a laser, since it refers to the style of cutting, not the type of blade)
I’m not worried if he blinds himself, possibly due to an unexpected specular reflection. But this contraption could easily blind someone else nearby. It only takes a microsecond, and saying “oops, sorry” wouldn’t be acceptable.
5mW is usually on the limit of being eyesafe; this is 1000 times more powerful than that!
IMNSHO, hackaday should not provide any publicity whatsoever for devices that could easily blind random passers by.
As the old safety poster put it, “do not look into laser with remaining eye”
eh, i am really upset also at this project but i wouldn’t go so far as to say hackaday shouldn’t spread projects with a significant safety problem. an awful lot of hacks here are dangerous, that prohibition would cut a wide swathe
maybe it was just a fluke but personally i thought it was brilliant how my middle school hired the 9-fingered man to teach shop class. “kids, this is dangerous” is a worthwhile exposition imo.
i’m not sure what to think of the fact that fooling around with lasers hasn’t produced a bunch of half-blind youtube stars…maybe you’re right and it makes it appear safer than it is but also maybe it is safer than it seems?? idk
I don’t want uninvolved passersby to be blinded, e.g. my daughter or me. I’m very deaf, so if I’m blinded (for whatever reason) I will commit suicide. Seriously.
I’m not averse to carefully calculated risk: I backpacked around India with a 14yo, and my daughter was making solo forced landings before she could even get behind the wheel of a car.
Glasses always. Based on wavelength. For everyone in the house, including cat 😂
What percentage of light would still get through/around glasses?
99.9% absorption might not be enough (7W, 5mW)
Here is where a full helmet with the crappy yellow screen hooked to a camera-on-a-chip comes into its own.
Singe everything else.
99.9% would be very bad, that would be OD3. The glasses I use with my fiber laser are OD6+ for that specific wavelength, so better than 99.9999% absorption.
Which is assuming the glasses you use are actually suited for the wavelength of the laser that is used.
With 6 nines, and assuming that each nine is an extra 20dB (does it work that way with laser light?) that is 180dB of rejection. That would mean that you won’t see the laser spot at all.
Or if you turn this around: If you can see the laser spotlightig your material, then maybe “something” is seriously off. Don’t buy laser goggles from aliexpress, amazon, etc…
Laser light attenuation measurement works just the same as any other electromagnetic wave. Just note that the attenuation spec is power, not voltage or amplitude. So each nine adds 10 dB, not 20.
Ok..
Lots of nervous opinions. And yes, they are absolutely ok. I’m inclined a little differently. If it can only blowtorch its way through balsam wood or black paint, it needs more wattage. That said I’d use it with a black out shield/box, internal camera with filtration and and external screen —- all doable for peanuts.
Goggles…good. Kids in goggles… good. Pets….out of my work space…even the goldfish.
There are plenty laser Cutter on the market with such powerfull lasers. Many without enclosure. I thought to buy one until I visited a fab lab where they had one with eclosure and wir exhaust system. The whole room smelled like open fire. And I dont wanna know what aerosols are created when cutting plastics. The danger of laser Radiation and fumes made ne rethink. I dont wat this in my house.
As a scroll/band saw doesn’t cut until something is pushed into the blade, this should function likewise. I suggest an optical mouse sensor be used to detect movement of the workpiece. No motion, no laser. If you want to be really fancy, you could modulate the power of the beam based on the speed of the motion.
yeah good idea. might be even easier to have a temp or photo sensor on the ‘beam dump’ side of the thing to detect if when it’s made it through
blades as a beam dump? any reason why? (i did not see an explanation of the choice in the project page and i will not be watching the video sorry thanks)
The sharp edges means minimal reflection(top surface width) and the tight angle of the blade faces means reflections are channeled further into the stack of blades and not reflected sideways.
oooh! i didn’t understand the orientation. they’re edge-on. thanks!
The video in case anyone was looking for it.
https://www.youtube.com/watch?v=1sBeiYIkn4k&cc_load_policy=0
“I too have a new toy, but considerably more practical. You are looking at an industrial laser, which emits an extraordinary light not to be found in nature. It can prowjekt a spot on the moon, or – at closer range – cut through solid metal – I will show you”………
https://www.youtube.com/watch?v=wzwPI1zJ9K0
User name checks out.
This is safer than the hundreds of thousand of other power tools that are hand fed. Tablesaws, jointers, grinders, drill presses and such can pull you into them. This can’t, all you have to do is protect your eyes like a lot of other tools.
Have you seen the laser rust removers? They are like magic, they cost a few grand though.
What is weird is that they warn people about eye exposure but then the videos of them seem to be using unprotected lenses to film them in operation.
They are a wide moving patch, but powerful enough to remove rust instantly, so you’d think they would kill camera sensors from accidental reflections.
And they use them on docked boats, so then I wonder what about the sea birds and passerby people?
“…as long as he follows his own advice and keeps his laser goggles firmly on his precious vision orbs.”
’nuff said, IMO.
This project is no more dangerous than Sugar Rockets or reloading ammunition or reroofing your home.
From a HACKADAY point-of-view, listing a URL is somewhat problematic since HACKADAY has international readers. Readers in the U.S.A. may refer to:
http://www.fda.gov/radiation-emitting-products/alerts-and-notices/consumer-safety-alert-internet-sales-laser-products
There are countless dangers thrown at an individual daily and DIY projects just puts one at a slightly higher statistic for self-induced injury. Nearly every tool or toy comes with some warning label regarding misuse; which is printed on the packaging or manual insert because lawyers demand it.
http://www.cdc.gov/nchs/fastats/accidental-injury.htm
Maybe some warning stickers in braille are apropos.
I LOVE the sarcasm in this labelling idea! Definitely up there with the “Do not look into death ray with remaining eye” sign!
I built in as much shielding/guarding/reflective path limiting as I could semi-reasonably get in there. That’s the function of the U-shaped orange part, an analog of the upper guide and blade guard on a bandsaw; it is made from laser blocking plastic specifically tested for these blue lasers. Yes, it does cut pretty well on this laser; a good confirmation that it absorbs in the blue range. The column blocks another quadrant pretty well.
This is never going to be a 100% safe tool, but I submit that its not significantly more hazardous than a bandsaw. The laser beam in question has a definite focal point; the beam spread away from there is quite significant. During testing (WHILE wearing laser safety goggles) I projected the laser beam onto a wall a few feet away. The power density falls quite rapidly as you get away from the focus; I didn’t even warm my wall up.
Its honestly mostly a “can I even build such a thing???” kind of project. Not actually a useful tool. The power level is just too low to do much functional cutting. Plus, it comes with all kinds of charring!
“I built in as much shielding/guarding/reflective path limiting as I could semi-reasonably get in there.”
Irrelevant.
Did you build in sufficient to guarantee that nobody else in the vicinity could be blinded?
How much personal liability insurance do you have?
Could you find a lawyer to defend you?
Suggestion to Webmaster
Can we have a “Ignorant and Happy” mode where users can opt to hide posts complaining about safety.
Don’t hold your breath. We’re still waiting for an edit button.
Then I would lobby for a killfile option, like any decent netnews reader had back in the day. I suppose a browser plugin could do that now. Hmm… added to the project list.
I was holding my breath just watching the video – would fume extraction be too whiney a demand?
Light handling tech at the very small…tiny lasers
https://www.nanowerk.com/nanotechnology-news3/newsid=69813.php