I have checked my sizes of the flag pattern, and the sizes of my block of wood. Carbide Create, when saved to G-Code makes whatever size it wants. I use Mach-3 for my cnc, and the G-code will try to make the stars bigger than my cnc machine. I’m new and have tried everything I know how. I can’t figure this one out.
step 1: look at your gcode using ncviewer.com … that is what CC created and wants to send to the machine. If that is right… it’s on the machine side
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Is it a metric to inch issue?
Is the output 25.4 times bigger than what you expect?
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Please post the source file (and notes on where it was sourced/how it was made using what application), .c2d, generated G-Code, step-by-step notes on how you are securing your stock and setting zero relative to it, and a photo showing an attempt at cutting and we’ll do our best to work through this with you.
Thank you for the response. My pattern is outside the graph on ncviewer. Does ncviewer’s graph stay the same, of does it change with the G-code?
Thank you for your response as well. It should not be a metric to inch, because I have tried both. I’m not sure how much bigger the output is as I have had to stop my machine before it went to the limits.
Thank you for your response. I will work on getting what you have requested. I really do appreciate the help.
I’m thinking the program is created in metric, but the machine is setup for inch. Are you using Mach 3 on a Shapeoko? I didn’t know Carbide Create could program a Mach 3 controller? There is a good chance I am wrong though. 
I use carbide create to generate the G-code and transfer it to mach3. I am using a cncest (chinese) machine. I wanted to learn on it, but I wish I had gotten a bigger machine to start with.
Are each of the bigger squares 1 inch on ncviewer?
I would recommend calibrating the machine in terms of movement — we discuss this in the context of our belt drive machines at:
but all you need to do is open a Log, send $$, then read the $100/$101/$102 settings and use those numbers for the calculations.
I believe the large squares on ncviewer are 1cm if your code is metric (g21) or one inch if the code is imperial (g20)
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From that ncviewer snapshot there, it seems like the G-code is configured in mm (G21) and then moves the cutter to X and Y values consistent in the ~120mm ballpark from X0Y0, so if the machine actually travels further than that it is likely a problem in your GRBL $100/$101/$102 settings as Will mentioned. They may be completely off, it all depends how you set them initially, and what the number of steps per mm is on your cncest machine.
Since I don’t know anything about MACH3 I’m confused. Isn’t MACH3 an actual CNC controller, not a G-code sender ? What does it do with the G-code file you generated ? Does your machine have a dedicated controller running GRBL, or is it controlled by a MACH3-based controller ?
My suggestion would be to draw a series of 1" squares — cut each out of a bit of scrap using a different toolpath and measure each — that should make obvious what is happening.
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I use carbide create to make the G-code, and Mach3 runs my machine.
I’ll give that a shot.
Mach 3 handles units differently than grbl.
If you jog 1mm, does it move 1mm?
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Where did you hear that? That would be fundamental breakage. Perhaps something to do with improper calibration?
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Sorry, my statement was unclear.
I meant that in terms of the way the steps per unit are set. When we calibrate our grbl machines, we always use steps per millimeter. Mach 3 sets in steps per unit and the default unit also is set.
Millimeters are only millimeters if the steps per unit are correct. That’s why I asked him what happens when he jogs one mm.
Following the hunch of @themillertree, I’d suspect that it will move one inch.
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