I've just bought the ORTUR LM2 20W laser engraver.
At $300 it is a seriously impressive piece of kit that performs many of the jobs that have been difficult - to say the least - at the DIY level.
Finally I have a machine that can produce PCBs with repeatable accuracy.
With a bit of playing it can also produce front panels, all-be-it in acrylic.
It won't etch metal directly but eats acrylic with ease.
For PCBs just spray acrylic paint onto the copper and then etch away the unwanted paint, then etch away the coper with FECl3.
Panels can be done in several different ways depending on the result you are after.
Either coat the metal panel with acrylic and burn away what isn't needed (ie negative printing) or reverse print on clear acrylic sprayed with paint.
It's also powerful enough to cut through 2.5mm black acrylic.
At $300 it is a seriously impressive piece of kit that performs many of the jobs that have been difficult - to say the least - at the DIY level.
Finally I have a machine that can produce PCBs with repeatable accuracy.
With a bit of playing it can also produce front panels, all-be-it in acrylic.
It won't etch metal directly but eats acrylic with ease.
For PCBs just spray acrylic paint onto the copper and then etch away the unwanted paint, then etch away the coper with FECl3.
Panels can be done in several different ways depending on the result you are after.
Either coat the metal panel with acrylic and burn away what isn't needed (ie negative printing) or reverse print on clear acrylic sprayed with paint.
It's also powerful enough to cut through 2.5mm black acrylic.
Unenclosed 20W laser? Seriously? (Well I had a bit of a delve and its 20W electric power, 5.5W laser power). Still, that's too powerful for unenclosed use, can damage eyesight at 500m if in the visible range from what I can find out. Class 4 is the highest classification of laser.
Safety of Class 4 visible-beam lasers
Safety of Class 4 visible-beam lasers
As long as you take reasonable precautions it is safe to use.
It's virtually impossible to look straight into the laser beam.
It's virtually impossible to look straight into the laser beam.
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Will be interested to hear about your experiences, but to be honest I recently bought a small CNC because those cheap hi-power lasers look very dangerous to me 🙂 (and ok, a CNC is slightly more useful for me).
Each machine has its drawbacks. The CNC is more expensive and can be less reliable for PCB manufacture.
It is the reflections off the work that are the main problem.
Then you might ask where does the vaporized material go? Hopefully not into your lungs.
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I spent 10 years in the 70's and 80's maintaining a factory full of manufacturing equipment. This encompassed several lasers in the 20 to 100+ watt range with the 100 watt CO2 laser modified "Tubelab style" to make around 200 watts for cutting the 40 mil thick ceramic substrates used to make some of the modules in the MX-300 series radios.
Achieving "mode" on this beast involved removing all covers and interlocks and aiming the unfocussed laser at a 1/2 inch thick sheet of asbestos. The asbestos target was mounted on wood, so you worked quick. A burn through got flames, which gets you in trouble.
You used Allen keys mounted on long Delrin rods to adjust the mirrors for the hottest spot on the asbestos. Each mirror was mounted on a metal cooling block elevated to somewhere beyond 25KV (meter pegged due to mods). Accidentally touching one of those blocks could kill you. Three people were hit by this beast in 10 years, one had to be revived with a defib. it was the only thing in that factory that truly scared me.
I left that group in 1984, but I still have two permanent blind spots in one eye due to incidental reflections off screw heads on the cutting table caused by the controller losing its mind. Even in 1977 the laser cutter ran "G code" loaded from paper tape that was punched on a Teletype machine.
Get a pair of decent laser goggles that are rated for the wavelength of your laser and have them on any time you are in the room with it. Sunglasses, and cheap goggles found on Amazon are likely useless since the laser wavelength is likely out of their working range.
I might have done several "experiments" with the laser, including a quick erase of a 2708 Eprom (reduced to shards with about 5 1 mS pulses), and some others, but at least I wasn't the idiot who clamped a front surface beam bending mirror in a pair of vise grips and burned his name in the ceiling tiles with the laser on full power CW.
Achieving "mode" on this beast involved removing all covers and interlocks and aiming the unfocussed laser at a 1/2 inch thick sheet of asbestos. The asbestos target was mounted on wood, so you worked quick. A burn through got flames, which gets you in trouble.
You used Allen keys mounted on long Delrin rods to adjust the mirrors for the hottest spot on the asbestos. Each mirror was mounted on a metal cooling block elevated to somewhere beyond 25KV (meter pegged due to mods). Accidentally touching one of those blocks could kill you. Three people were hit by this beast in 10 years, one had to be revived with a defib. it was the only thing in that factory that truly scared me.
I left that group in 1984, but I still have two permanent blind spots in one eye due to incidental reflections off screw heads on the cutting table caused by the controller losing its mind. Even in 1977 the laser cutter ran "G code" loaded from paper tape that was punched on a Teletype machine.
Get a pair of decent laser goggles that are rated for the wavelength of your laser and have them on any time you are in the room with it. Sunglasses, and cheap goggles found on Amazon are likely useless since the laser wavelength is likely out of their working range.
I might have done several "experiments" with the laser, including a quick erase of a 2708 Eprom (reduced to shards with about 5 1 mS pulses), and some others, but at least I wasn't the idiot who clamped a front surface beam bending mirror in a pair of vise grips and burned his name in the ceiling tiles with the laser on full power CW.
I've been experimenting, I'm only trying to make home brew PCBs.
The best results so far have been with masking tape on the copper surface.
Use a very low power 15% to burn away the paper tape and then gently remove the adhesive with acetone.
This is far superior to CNC cutting away the unwanted copper.
The masking tape then acts as a perfect mask for acrylic paint which then acts as an etch mask.
The best results so far have been with masking tape on the copper surface.
Use a very low power 15% to burn away the paper tape and then gently remove the adhesive with acetone.
This is far superior to CNC cutting away the unwanted copper.
The masking tape then acts as a perfect mask for acrylic paint which then acts as an etch mask.
I think it sounds interesting. As for safety, the glasses make sense, but the most important thing is caution and paying attention. I use a number of power tools on a regular basis - table saw, numerous routers, a jointer, a bandsaw and (so far) I have all ten fingers. Just about anything used inappropriately, and without caution, can be harmful.
My main issue at the moment is that the acrylic paint still creeps under the tape.
I've ordered some "high definition" modelling tape which might be better.
I've ordered some "high definition" modelling tape which might be better.
The problem is it doesn't only emit the laser wavelength "color", but also nasty infrared & UV light, unless there are filters installed.
But with 20W I could lighten up the hill trees near my home.
I'd second the laser glasses PPE for whatever wavelength. It's your eyes, man - and it's the unexpected that can get ya...
I have successfully used masking tape for etch resist ever since I was a kid. After putting the tape on the board take something with a smooth rounded end (butt of a screwdriver, or back side of a spoon) and rub it all over the tape to press it tighter to the board.
Power tools can hurt you, but you can see the dangerous parts in action. I do not know about this particular laser, but I'm guessing that it is not using visible light. If that's the case, its what you can't see that can blind you. Things that don't necessarily reflect visible light can reflect IR light.
CO2 lasers are infrared. Lower power ones are used for surgery. Normal machine shop practice is to coat the metal with a clear photo resist that turns black when heated by the laser instead of engraving and filling. When used as photo resist the entire piece is painted with a covering often black and then the area to be etched is removed.
Let's see, make a cover for the entire assembly that blocks all light while working and with a fan driven vent to exhaust high outside or go blind. Doesn’t seem to be a tough decision. Of course the advantage of no cover is just might teach an unauthorized fiddler an important lesson.
Sorry if this seems a bit nasty, but I have seen too many shop injuries.
Let's see, make a cover for the entire assembly that blocks all light while working and with a fan driven vent to exhaust high outside or go blind. Doesn’t seem to be a tough decision. Of course the advantage of no cover is just might teach an unauthorized fiddler an important lesson.
Sorry if this seems a bit nasty, but I have seen too many shop injuries.
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I've just bought some "Easy Peel" A4 labels.
Finally success.
I'm running the laser at 800mm/sec and 35% power. This laser is NOT infra-red, the beam is in the visible end of the spectrum. (It may well contain IR radiation but the beam is clearly visible).
I've managed to get down to 0.5mm traces at 0.5mm spacing which is fine for my DIY work.
It's a bit of a pfaff peeling the cut paper off the board and then spraying the acrylic but FINALLY I have a technique that works and is repeatable.
Finally success.
I'm running the laser at 800mm/sec and 35% power. This laser is NOT infra-red, the beam is in the visible end of the spectrum. (It may well contain IR radiation but the beam is clearly visible).
I've managed to get down to 0.5mm traces at 0.5mm spacing which is fine for my DIY work.
It's a bit of a pfaff peeling the cut paper off the board and then spraying the acrylic but FINALLY I have a technique that works and is repeatable.
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C02 is infrared that is why it cuts so well. Although there may be some other emission or reaction from the material it is illuminating. Of course your laser may not be all that is advertised. Does make getting the right protective lenses a bit tougher.
At visible red 10 mW may be enough to cause damage.
At visible red 10 mW may be enough to cause damage.