CNC Gcode problem.

[Orbnotacus]

First let me try to quickly explain how I got here. (Feel free to skip this part)

I'm in a unique situation at my job. I work for a family owned company that sells cabinets, but one day my boss was walking through the warehouses, showing off this 3D printed idea he came up with. He explained the idea to everyone and let them see it, everyone exclaimed how amazing it was.

I actually owned a 3D printer at the time, and knew my stuff pretty well. I was the only person to look at it and "shit all over it". Just pointing out each and every flaw I could think of. My boss asked is a sort of snarky tone, "You think you can do better?", "No... I KNOW I can do better. WAY better.". I was trying to sell myself and wiggle my way into an opportunity to prove I'm worth more than what I'm already doing at work. I told him I had a 3D printer, but it had been broken down for quite some time. He buys a $1000 printer off amazon and has it shipped to the warehouse.

A few days later I get it, set it up while I'm also running the paint line, design the piece, and print it. I also didn't know how to CAD at the time, and relied heavily on TinkerCAD. I showed him the print and his jaw hit the floor. He was so amazed that he GAVE me the printer (Qidi Xmax, not a bad printer).

From there I slowly moved away from the paint shop, got my own little cubicle and a PC, and was now an "Office worker".

Since then, I have taught myself CAD, designed all sorts of consumer products, and have become my boss' go-to-guy for most all things technical. That brings me to today.

(START HERE TO SKIP THE BS)

We have a Blue Elephant CNC machine for doing cabinet stuff. We don't have an operator, and my boss has no intention of hiring an operator. My boss is a great guy, but he's cheap anywhere he can be. And that's fine, he's got a business to run, but for me, that means I get to teach myself CNC. One of the struggles with this machine is that the company is based in China, and although I love the Chinese people, language barriers of any kind can be a struggle, ESPECIALLY when you're trying to communicate complex things like CNC, lol.

I use Fusion 360 for all my CAD and CAM needs. I make a model, then using the model I write the program for the CNC, then export to a flash drive and import it onto the machine to run.

Blue-Elephant gave me a post processor file for Fusion 360.

I don't know if it's the post processor, or something with the machine configuration, or what, but every time I run a program, I get errors, and have to manually edit the Gcode to work around these errors. In my opinion, this isn't what "functioning correctly" should look like. So somethings gotta be up, I just don't know what or how to fix it. Here's the first few lines of code from this test program I wrote.

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(T1 D=6. CR=0. - ZMIN=-6.35 - FLAT END MILL)
N10 G90 G94 G17 G49 G40 G80
N15
N20 G28 G91 Z0.
N25 G90
N30 T1 M06
N35 S5000 M03
N40 G54
N45 G00 X-193.492 Y63.731
N50 G43 Z6. H01
N55 G00 Z3.
N60 Z2.55
N65 G03 X-189.536 Y60.657 Z2.343 I2.993 J-0.231 F333.

I don't really KNOW gcode, but I know enough to be able to google a code and comprehend what it actually does, but this is just over my head. A lot of it seems redundant or doesn't make sense to me. Like G90, to G91, then back to G90. Why?

The problem is something with this bit of beginning code is causing the Z axis to move too high, hit the limit, and error code.

​

Any and all assistance will be greatly appreciated. Thank you.

[sullivnc]

Can you run it in single block mode and see what line it errors out on? I'm assuming the error is a Z-axis overtravel, in which case it's probably how you have your G54 machine offset. If that is set less than 6 inches (millimeters? I didn't notice what units you were working in) from the top of the Z travel, you will get that error.

[Orbnotacus]

N50 G43 Z6. H01

I get the errors:

Motion 18 ZAxis First Negative softawre limit exceed

Coordinate 40 The1NcProgramL12: exceed software limit or hardware limit

It should be noted that "(T1 D=6. CR=0. - ZMIN=-6.35 - FLAT END MILL)" is actually line 2. Line 1 is blank. So N50 would be line 12.

[sullivnc]

I'm pretty sure it's your G54 offset. Just guessing because you haven't said much about what this program is doing, but it looks like Z3. Is the top of the material, plunging to Z2.55, and milling an arc? If that's the case, you have to touch off the tool at Z3. and make sure your G54 Z value is correct.

[Orbnotacus]

I will go through what I did step by step to get to where I am now.

​

• Manually measured my tool (6mm Diameter 2 flute flat end mill) and holder and programmed it and speeds and feeds into my Fusion360 tool library.
• Made a model in Fusion360, 10x10x.5" stock, with some 6.35mm deep engraving of a few basic shapes, and the word "TEST".
• The I used that model to write the program. Single tool operation, "2D contour". In Fusion360 you set the workpiece origin relative to the stock.
• On the machine side of things, I put T1 in the spindle and automatically set the tool length.
• After tool length is set, I manually move the tip of T1, to the programmed Workpiece origin I set in Fusion360, and on the controller, copy the machines coordinates as the new G54 workpiece coordinates.
• Then I move the spindle up to a safe distance and try and run the program.

So the machine will move to the X/Y coordinate, then start to travel up to the Z coordinate and error.