Adding Laser to my CNC

[Larsson55]

Apologies if I'm in the wrong place,

I have a table top cnc mill approx. cutting area 42"x36", 3 axis, 4 stepper motors, VFD controlled water cooled spindle, Mach3 software, all made with 3/8" aluminum stock. Its for a hobby use and was thinking to add a laser so I can learn what they can do.

I have no idea about lasers and searching it gets more confusing with the variety of lasers available and their cost. If I get a laser it will be used to cut/engrave plywood, MDF and 1/8" thick aluminum.

Can you give me an idea what I should be looking for and perhaps a link of a suitable laser?

Thanks

[Roehrenonkel]

Hi Nicolas,
 
yeah, lasers are fun. 8-)
I got myself a laser as well for my cnc.
A 40W input (10W optical power) diode-laser with air-assist.
(Around 200,- € from Aliexpr.)
It's okay for cardboard, MDF and plywood-cutting.
But forget about cutting aluminium with it.
You can scratch the surface a bit (black anodised heatsinks work well).
.....but you got a mill for that. ;-)
Get some eye-protection and smoke-extraction too.

Good luck

[Larsson55]

Hi Nicolas, yeah, lasers are fun. I got myself a laser as well for my cnc. A 40W input (10W optical power) diode-laser with air-assist. (Around 200,- € from Aliexpr.) It's okay for cardboard, MDF and plywood-cutting.
But forget about cutting aluminium with it. You can scratch the surface a bit (black anodised heatsinks work well).
.....but you got a mill for that. Get some eye-protection and smoke-extraction too. Good luck

Thanks mate for your time, looks like all lasers are made in China, would you have a link for the one you bought? I know about eye protection but why smoke protection?

[thm_w]

The smoke/material will build up on the lens and the laser will heat it up and destroy it.
https://www.reddit.com/r/ChineseLaserCutters/comments/qdj1sm/burnt_out_lens_what_could_have_caused_it/

[fourfathom]

I've got a CNC mill (Shapeoko) and considered looking for a laser head so I could use it for "engraving" legends in anodized and powder-coated aluminum faceplates.  I ended up buying an inexpensive laser mill (a refurbished X-Tools D1).  I probably want a more powerful laser (they are available for this machine) to speed things up, but it works quite well and burns a much finer line than I can reasonably mill with the CNC.  I haven't carefully measured the "engraved" line width, but it looks like about 0.005" .  It's also less sensitive to surface leveling than the CNC router is.

Putting a laser head on the CNC mill would have worked, assuming the laser-control software could be adapted, but since the laser mill doesn't have to drag a spinning router bit across the work surface the heavy-build of the CNC mill isn't necessary.  And I still regularly use the CNC mill so I don't have to tear things apart and re-calibrate when switching tasks.

[Roehrenonkel]

Thanks mate for your time, looks like all lasers are made in China, would you have a link for the one you bought? I know about eye protection but why smoke protection?

Hi again,
....yes, even german cars are comming now from Tshina! :-(
I think i got the E40 80W-set:
https://de.aliexpress.com/item/1005002428418897.html
You could also try:
https://de.aliexpress.com/item/1005003888432181.html
Smoke-extraction/protection:
Depends on the smoke you'll create.
You can wear a gas-mask or get rid of the smoke with
a vacuum-cleaner (here with a water-filter) from under
the honey-comb-grid.
When i cut a spraying-template out of "Forex" for a good friend
of mine (car-hater) i had a headake for two days.....
And that bloody fool didn't even use it!

Ciao4now

[Larsson55]

Many thanks again, the links helps a lot to get a feel about lasers however I have much to learn about them. Now I understand about the smoke, I thought lasers do not create any but I was wrong

[Roehrenonkel]

Hi Nicolas,
 
always glad when my input can help.

Smoke, gasses etc.:
And not to forget about fire-protection. ;-)
Especially with forced air-flow from the air-assist.
A wet rug might do.

Ciao4now

[LinuxHata]

If you really want metal engrave, you should be looking into 200w models. If you want metal cutting and willing to do oxygen assist, then 400w co2 laser will work. If you into metal cutting, consider fiber optic laser. But none of these are in shape which allows simple mounting onto CNC.

[Larsson55]

If you really want metal engrave, you should be looking into 200w models. If you want metal cutting and willing to do oxygen assist, then 400w co2 laser will work. If you into metal cutting, consider fiber optic laser. But none of these are in shape which allows simple mounting onto CNC.

Thanks for the tip but have no interest in metal cuts. If I ever get a laser it will be just for hobby use on plywood or MDF but so far looks complicated to get it working with my existing cnc setup

[fourfathom]

If you really want metal engrave, you should be looking into 200w models. If you want metal cutting and willing to do oxygen assist, then 400w co2 laser will work. If you into metal cutting, consider fiber optic laser. But none of these are in shape which allows simple mounting onto CNC.

My "engraving" is just ablating the surface treatment, not actually removing the underlying metal.  The 5W laser on my XTOOLS D3-Pro does take a long time to do the job, but it works.  If I need more speed I will get a stronger laser.  Here is an image of what I am doing with a powder-coated aluminum faceplate.  This took one hour of burning:

[Larsson55]

That's an excellent job you did there mate, perhaps one day I may be able to do something similar

[Old Printer]

I have been running co2 lasers as my day job for 20 years. They don't cut, they burn, so if a material can be burned it can be considered laserable in a co2 machine. Many materials, like plastics, give off toxic gasses when burned. PVC releases chlorine gas, which besides being toxic is very corrosive to metals. All of this makes a very strong case for a sealed working area. I have always used a one hp high volume dust collection pump as a minimum. Unless removed quickly smoke will condense on the lens and mirrors, it will then absorb the beam energy and ruin them. Co2 is the wrong wavelength for metals. A 75 watt machine will cut a half inch of acrylic, but barely leave a mark on tin foil, though it will do a nice job engraving away the anodized coating on aluminum. None of this makes what you want to do impossible, it's just that there are a lot of things to consider.

[Old Printer]

I have been running co2 lasers as my day job for 20 years. They don't cut, they burn, so if a material can be burned it can be considered laserable in a co2 machine. Many materials, like plastics, give off toxic gasses when burned. PVC releases chlorine gas, which besides being toxic is very corrosive to metals. All of this makes a very strong case for a sealed working area. I have always used a one hp high volume dust collection pump as a minimum. Unless removed quickly smoke will condense on the lens and mirrors, it will then absorb the beam energy and ruin them. Co2 is the wrong wavelength for metals. A 75 watt machine will cut a half inch of acrylic, but barely leave a mark on tin foil, though it will do a nice job engraving away the anodized coating on aluminum. None of this makes what you want to do impossible, it's just that there are a lot of things to consider.

[Larsson55]

Much appreciate your input Old Printer, I only started "thinking" to get a laser for my cnc about 2 weeks ago and the idea was lasers must be something "simple" kind of plug & play however the more I search the more confusing lasers become. I have all Winter ahead to learn about lasers and right now the verdict is "forget lasers".