I like to get one of those cheap China lasers and have a few questions, and since there are a quite a few experts here....
I like to use standard G-code which I can generate from Fusion360 or similar CAD software. Hence I like to change the controller to a one that can work with LinuxCNC. I don't think I have much demand for Moshi software.
Cheap China laser - materials, power, G-Code - need some feedback.
Moderator: baker
Re: Cheap China laser - materials, power, G-Code - need some feedback.
Cut will be mainly PMMA and EVA foam
My questions:
Can I simply replace the controller with a TB6560 or similar?
I like to control vie LPT/Serial Port for now. Are there better controllers?
In case 'yes, can do':
Can I control the laser power via the PC software (i.e. LinuxCNC)?
Do I need Z-Axis control?
Laser have Z-Axis?
Can I still engrave with the new controller? (mainly letters on PMMA)?
How thick PMMA I can cut with what power?
Think will be mainly 3mm or so.
How thick EVA foam I can cut, in case anybody knows?
Can be easily 30mm or more.
Not sure if I should take the normal 40W or go for higher wattage. I like to have the option to cut 5mm PMMA or so.
My questions:
Can I simply replace the controller with a TB6560 or similar?
I like to control vie LPT/Serial Port for now. Are there better controllers?
In case 'yes, can do':
Can I control the laser power via the PC software (i.e. LinuxCNC)?
Do I need Z-Axis control?
Laser have Z-Axis?
Can I still engrave with the new controller? (mainly letters on PMMA)?
How thick PMMA I can cut with what power?
Think will be mainly 3mm or so.
How thick EVA foam I can cut, in case anybody knows?
Can be easily 30mm or more.
Not sure if I should take the normal 40W or go for higher wattage. I like to have the option to cut 5mm PMMA or so.
Re: Cheap China laser - materials, power, G-Code - need some feedback.
Replacing the controller is pretty stright forward, getting the new controller to work as expected can be tricky.
I started a project based on MarlinKimbra for my machine and it is listed on Instructables as well for all the details, might be of interest for all the problems that come along with these chinese machines.
You can use basically any CNC controller that has support for lasers but you should decide first what you want to do and how.
Only expensive commercials controllers will offer you a printer driver that works for all programs you might use, normal solutions either need external programs to generate the gcode or plugins for progrmas like Inkscape.
LPT port control is a bit outdated, USB, SD and WiFI are used these days.
Having a lifting table to get different work heights certainly helps with engraving jobs but adding them to existing firmwares either means finding the right specs as used in the firmware or to modify the firmware to your needs.
Engraving support is only a thing of the Gcode generated unless you mean 8bit photo engraving.
3mm acrylic is no problem for a 40W CO2 laser, speed, power and thickness possible depend on your settings and what you need. For 3mm I would say around 10mm/sec @40% power should work in one or two passes - you don't want to use your laser at full power...
Cutting 30mm foam is not going to happen if you require more or less straight edges.
Do some reading on focal lenghts, laser spot size and usable cutting depth - it becomes clear when you see some related pics.
To put it short it is best to use a hot wire cutter for foam that thick otherwise wou will need quite a high pressure for your air assist (at close range!) and a lens with a really long focal lenght.
40W should be plenty for your purpose unless you are after extreme speeds but then again you would consider a cheap chinese system
I started a project based on MarlinKimbra for my machine and it is listed on Instructables as well for all the details, might be of interest for all the problems that come along with these chinese machines.
You can use basically any CNC controller that has support for lasers but you should decide first what you want to do and how.
Only expensive commercials controllers will offer you a printer driver that works for all programs you might use, normal solutions either need external programs to generate the gcode or plugins for progrmas like Inkscape.
LPT port control is a bit outdated, USB, SD and WiFI are used these days.
Having a lifting table to get different work heights certainly helps with engraving jobs but adding them to existing firmwares either means finding the right specs as used in the firmware or to modify the firmware to your needs.
Engraving support is only a thing of the Gcode generated unless you mean 8bit photo engraving.
3mm acrylic is no problem for a 40W CO2 laser, speed, power and thickness possible depend on your settings and what you need. For 3mm I would say around 10mm/sec @40% power should work in one or two passes - you don't want to use your laser at full power...
Cutting 30mm foam is not going to happen if you require more or less straight edges.
Do some reading on focal lenghts, laser spot size and usable cutting depth - it becomes clear when you see some related pics.
To put it short it is best to use a hot wire cutter for foam that thick otherwise wou will need quite a high pressure for your air assist (at close range!) and a lens with a really long focal lenght.
40W should be plenty for your purpose unless you are after extreme speeds but then again you would consider a cheap chinese system
Re: Cheap China laser - materials, power, G-Code - need some feedback.
Thanks for your reply.
So how do I know what controller supports lasers? After some reading the TB6560 seems suitable for lasers as some other managed to get it to work.
For the EVA, focus isn't really a big issue. I just try. And if 30mm fails I simply use 3 x 10mm and glue them together.
For the engraving, well, worst case, I do have a cheap China CNC mill that can do that too. That uses parallel port too. I have an old PC for that with LinixCNC on it.
G-Code. My China CNC uses G-Code. I create some 2D, then generate the G-code with Visualmill. Now I use Fusion360 (gee that is good, and free! It's owned by the AutoCAD people) which has a CAM function to generate G-code too, but I haven't tried it yet.
Seems I am ready to go....
So how do I know what controller supports lasers? After some reading the TB6560 seems suitable for lasers as some other managed to get it to work.
For the EVA, focus isn't really a big issue. I just try. And if 30mm fails I simply use 3 x 10mm and glue them together.
For the engraving, well, worst case, I do have a cheap China CNC mill that can do that too. That uses parallel port too. I have an old PC for that with LinixCNC on it.
G-Code. My China CNC uses G-Code. I create some 2D, then generate the G-code with Visualmill. Now I use Fusion360 (gee that is good, and free! It's owned by the AutoCAD people) which has a CAM function to generate G-code too, but I haven't tried it yet.
Seems I am ready to go....
Re: Cheap China laser - materials, power, G-Code - need some feedback.
The TB6560 is just a stepper motor driver and not one of the best out there if I might add - check Google for problems with them.
What type of Gcode you need will highly depend on the firmware you use on the Arduino as they all work differently.
GRBL is very popular for everything CNC related and has some options to use a laser too, although it is not my first choice as it is not really designed for the chinese laser cutters.
Some hardware mods or changes in the firmware are required to make it work on a chinese laser.
For Marlin there are several firmwares out there that support lasers and IMHO it is easier to convert a machine to use Marlin than GRBL.
I don't know if Fusion360 will work for generating usable Gcode as I don't use it, so you might want to read up on that first or seek more modern alternatives.
What type of Gcode you need will highly depend on the firmware you use on the Arduino as they all work differently.
GRBL is very popular for everything CNC related and has some options to use a laser too, although it is not my first choice as it is not really designed for the chinese laser cutters.
Some hardware mods or changes in the firmware are required to make it work on a chinese laser.
For Marlin there are several firmwares out there that support lasers and IMHO it is easier to convert a machine to use Marlin than GRBL.
I don't know if Fusion360 will work for generating usable Gcode as I don't use it, so you might want to read up on that first or seek more modern alternatives.