KSum
Posts: 23
Joined: Wed Sep 24, 2014 10:25 pm

Laser cutter on QU-BD Two-Up printer.

So I purchased and assembled a Two-Up printer. Pretty basic stuff and seems like a decent printer.

Instead of installing the included extruder, I installed an L-Cheapo laser cutter/engraver.

The setup should be similar to an SLA printer to control the laser on/off, but I can't seem to work out the right profile in Simplify3D.

Any help would be greatly appreciated.

NOTE: The Z axis is reversed so the material moves closer to the laser as it cuts/etches the next layer.
JoeJ
Posts: 1435
Joined: Sun Feb 16, 2014 10:52 am

Re: Laser cutter on QU-BD Two-Up printer.

What commands are you using to turn the laser on and off? I wonder if you can just place those in your retraction script so that the laser it turned off right before the printer moves to a new location, and then turned on again when it gets there
KSum
Posts: 23
Joined: Wed Sep 24, 2014 10:25 pm

Re: Laser cutter on QU-BD Two-Up printer.

The makers of the L-Cheapo say any of the extruder (stepper) lines don't have the necessary amperage or signal to power the laser. They connect it to the heater line. But I saw in the Simplify3D Firmware Configuration an SLA tab that uses the M600 and M601 commands to turn the laser on and off. I just don't know how to make that the default "extruder" that is used.

The makers of the L-Cheapo hook it up to the extruder heater line and leave it on and just make the travel speed while not printing high enough that the laser doesn't have time to burn that spot. It slows when "printing" and is able to burn. I'm not crazy about that method. I would rather see it turn off and on like an SLA printer should.
KSum
Posts: 23
Joined: Wed Sep 24, 2014 10:25 pm

Re: Laser cutter on QU-BD Two-Up printer.

I found another laser module that advises using the D9 (auxiliary fan) connector on the RAMPS board to control the laser.
M106 to turn it on, M107 to turn it off. I suppose I can generate the G-Code and then edit all of the extruder commands to use those codes, but I was hoping for a simple configuration change in Simplify3D.
JoeJ
Posts: 1435
Joined: Sun Feb 16, 2014 10:52 am

Re: Laser cutter on QU-BD Two-Up printer.

I've done this before. It isn't hard. Just click "edit process settings", and then go to the G-Code tab. You will need to enable the "Include M101/M102/M103 commands" options. When you do this, the software will now place an M101 right before the printer would start extruding, an M102 before any retractions, and an M103 before the extruder turns off. You can use those commands to trigger the laser too. But since these M101/M102/M103 commands are based on retractions, I would also make sure that retraction is enabled on the Extruders tab, and then go to the Advanced tab and disable "only retract when crossing open spaces". This way you will always have a retraction (and thus the M101/M102/M103 commands) anytime the extruder is moving to a new location.

Now, we just need to convert the M101/M102/M103 commands into what your laser actually uses. So go to the Scripts tab and add the following commands to your "additional commands for post processing" section.

Code: Select all

{STRIP "M106"}
{STRIP "M107"}
{REPLACE "M101" "M106"}
{STRIP "M102"}
{REPLACE "M103" "M107"}
That will remove any fan commands that were in the file to begin with (since those also use M106/M107), and then it will replace each M101 with M106 to turn the laser on, and replace M103 with M107 to turn the laser off. All of the M102's are just removed because we don't care about the actual retractions.

Thankfully the software is very customizable, so I've been able to use it for a lot of different applications with only a few changes :D
KSum
Posts: 23
Joined: Wed Sep 24, 2014 10:25 pm

Re: Laser cutter on QU-BD Two-Up printer.

That's awesome!! Thank you!
KSum
Posts: 23
Joined: Wed Sep 24, 2014 10:25 pm

Re: Laser cutter on QU-BD Two-Up printer.

Thanks again for your help. The process worked flawlessly and after some tinkering and hair pulling and more tinkering I ended up with a pretty good result.
20150830_145512.jpg
JoeJ
Posts: 1435
Joined: Sun Feb 16, 2014 10:52 am

Re: Laser cutter on QU-BD Two-Up printer.

Awesome! Glad you got everything working!
dunginhawk
Posts: 39
Joined: Mon Jan 19, 2015 10:15 am

Re: Laser cutter on QU-BD Two-Up printer.

would this exact change work for using a CTC SLA resin printer?
JoeJ
Posts: 1435
Joined: Sun Feb 16, 2014 10:52 am

Re: Laser cutter on QU-BD Two-Up printer.

Yea, it's the same concept. SLA is basically a laser cutter, just with extra layers ;)

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