[baronjutter]

So my makerspace built their own laser inside the shell of an old laser. All the mechanics work great, the laser cuts nice, but we're having a hell of a time getting cuts at 1:1 scale.
Our controller is this X7 DSP Controller card for CO2 Laser Engraving/ Cutter with color screen

In the "manufacturer settings" there's an option to scale the X and Y, but after 2 hours adjusting the numbers trying to get it printing correctly it always seems a bit off when we go back to cut again or cut something of a different size. Does anyone have any tips or insight on getting the laser calibrated and cutting to perfect 1:1 scale?

[crob09]

Not enough information, can you answer the following questions so I can help?
1.) Are you uploading Firmware to that device? It's a "Serial Controller" and will require an Interpreter to receive from the PC, if the Firmware isn't correct the units maybe off.
2.) What CAD CAM and Machine software are you using? Be sure to check the scale when producing a cut path, also when producing the image.
3.) How out of scale is it? Are there any areas larger than others, or does anything taper anyplace over many passes? If so, it could be a machine calibration issue, consider looking at belts or screws that drive the machine.

[baronjutter]

Thanks for the quick reply! I'm not sure if I'm "uploading firmware". I'm using the options within the lasercad software which communicates with the laser controller, it's reading settings off the machine and then saving those settings to the machine.
We are using the "lasercad" software that came with the X7 DSP controller, it's set to mm and no scale options.
It's perfectly consistently out of scale depending on what we have the machine's X and Y scale values set to (something about pulses?). Lowering the number makes the cutting bigger, increasing it makes it smaller. I'm away from the machine right now but I can take screen shots and get more info if it will help solve things.

[crob09]

Thanks for the quick reply! I'm not sure if I'm "uploading firmware". I'm using the options within the lasercad software which communicates with the laser controller, it's reading settings off the machine and then saving those settings to the machine.
We are using the "lasercad" software that came with the X7 DSP controller, it's set to mm and no scale options.
It's perfectly consistently out of scale depending on what we have the machine's X and Y scale values set to (something about pulses?). Lowering the number makes the cutting bigger, increasing it makes it smaller. I'm away from the machine right now but I can take screen shots and get more info if it will help solve things.

Alright, so as I noted this is a Serial Device so it's using Serial Software to send Packets to the Controller. The Scale Options are set, they are in MM's as you note, the Diameter of the Laser will change based on PWM settings, these are the Pulses you speak of.

The Cut will require an Offset, so, you need to get a happy Diameter and set that in your CAM software not CAD software "LaserCAD", note the "CAD" in "LaserCAD" I don't see CAM in the name.
Once you specify the Offset each part should come out the same and accurate, think of the laser dot at (3.14mm) as a 3.14mm end mill, you wouldn't cut on the line because you would lose 1.8 mm * 4 sides.

[baronjutter]

What is a CAM software? Lasercad is the only program that came with the controller, it's how you access all the laser's attributes. It basically lets you set all the options as you would on the physical controller but from your computer then upload those settings to the laser controller hardware.

What's a happy diameter? Cut circles and adjust the settings until I get a perfect circle the correct 1:1 diameter?

[crob09]

Sorry by "Happy Diameter" I'm trying to say; set the laser dia to whatever you want, one setting will be better than the other depending on material and thickness.
CAM software maybe Vectric Aspire, or MasterCAM, or GibbsCAM, there are literally hundreds of different players n the market, you will have to decide what's best for you, some open source stuff includes Slic3r, but that's for 3D-Printing and not for offset cutting.
I really like Vectric Software myself.
LaserCAD is CAD software, you use it with Vectric to get good cuts, use the Laser Diameter you choose based n PWM (Pulse Width Modulation), once you have that number use it as a cutting tool dia in Vectric. LaserCAD probably comes with Machine Software that sends the information to the Controller.
Vectric will generate a cut path, after that select "Save" and find a "Post" for your machine.
Either way, it's most likely an offset or Drawing problem.

[baronjutter]

I was told the only software that could be used with this controller was the software that came with it, I know that's a common criticism of this controller. This Vectric program can replace the machine's software, or at least communicate with the laser?

Oh I managed to find a screen shot of the exact screen I've been trying to solve my problems in by adjusting the top two numbers.


You're saying my solution isn't with adjusting these numbers, but by using different software?

[crob09]

Not sure if the Interpreter will accept G-code or if the LaserCAD outputs something different. LaserCAD maybe machine software also. (Pronterace for open-source USB Serial Control), but the software looks like CAD to me. There should be a postscript someplace for your machine, not sure I'd have to look at Vectric but I bet it would work.
Looks like "Datum" is the problem based on screenshot: https://en.wikipedia.org/wiki/Datum_reference
How Much are your parts out from end to end? If you measured the full X travel vs what you want in real life, what's the difference?
Enter Positive in Datum maybe.

Also nice... still using Windows XP!

[baronjutter]

That's just a screen shot I found of the screen online, not actually our setup.
When we first started cutting it was way out. Someone needed a 30x30mm box and it came out closer to 40mm. So we played with those X and Y settings until the box came out 20x20. But then when I tried to cut 300x300 it came out more around 310mm. Played and played with the X and Y until I was about as spot on as I could get, but still didn't feel perfect. I also had to vary the X and Y by a microscopic amount to have it right.

[crob09]

That's a firmware/ settings issue.
A configuration and logarithmic problem, hence my conclusion, fix your settings either in Firmware or in the Software.

Settings: 200 steps = 5/16 | 7.9375 mm
VS
Settings: 200 steps = 11/32 | 8.7313 MM
= 0.7938 * 10 units = 7.9mm

Or say you use 8MM vs 7.9375MM...
0.0625*10 units = 0.625

Think of the math and compounding over distance...

You need to configure the Firmware, Machine, or Software.
Maybe Firmware isn't a choice, if not change the pulley system or screws on the machine, otherwise build a Postscript that makes up for the problem.

[baronjutter]

I'm still rather a layman at all this so 90% of your advise is probably flying right over my head. So you're saying the solution isn't in this "manufacturer parameters" screen and we adjust the settings somewhere else? Do you know how to adjust the firmware on this specific controller? I'm not sure how I'd adjust the mechanics.

[crob09]

I'm still rather a layman at all this so 90% of your advise is probably flying right over my head. So you're saying the solution isn't in this "manufacturer parameters" screen and we adjust the settings somewhere else? Do you know how to adjust the firmware on this specific controller? I'm not sure how I'd adjust the mechanics.

It's either something simple in the CAD software or CNClaser software setup, for example the image isn't being scaled properly (it's being draw to 10mm but you expect the machine to cut something 5mm). Or another example, the settings for the machine are not being entered or haven't been entered into the UI (User Interface) properly.

Or something more complex, like the Firmware, for example GRBL https://github.com/grbl/grbl .
The Logic Controller inside that box with the Screen on it uses an Interpreter that's programmed for a specific thread pitch or sprocket O.D. and Motor, for example (Another possible problem... Mechanics); if the motor is a .9-deg step angle it will take .9*400=360-deg, or 400 steps per revolution v.s a 1.8-deg motor giving 200 steps per revolution, check the motors.

So we have three systems to cover:

* CAD-CAM & Machine Software. (Start with the simple fix before going to something more complicated).
* Mechanics (Screws | Belts, Motors).
* Firmware (Parallel Machines Don't Use This). Contact the manufacturer if you feel this is the trouble, you may require an ISP programmer if the PBA doesn't have an FTDI IC (Arduino PBA's).

[GeneMpls]

That controller is sold by Lightobject and they have a pretty good forum for this kind of problem. Lightobject.com Support Forum ? Index page ( go to 'DSP Controller for CO2 laser') Lightobject seems a pretty good company IMO.

The guy with the knowledge seems to be Tech_Marco but I think I read that he was leaving for China for a while to work with the Chinese companies that he sources from. The X7 is not built by Ruida (pretty sure anyway) but it uses
a slightly truncated version of RDworks which is the Ruida software.