Shorten Your G-Code Using a WHILE Loop! | CNC Macro Programming Tutorial

@GCodeTutor demonstrates how to remove a large amount of material writing only 9 lines of G-code.

As we saw in other videos in this series of CNC programming tutorials, Macro B variables are a great way to simplify your G-code programs and make them easier to read and modify.
In this video, Marc Cronin shows how to write a Macro program using a WHILE loop.

Stay tuned for more machining videos!

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#Gcode #CNCprogramming #macroprogramming

[faradynemotors]

I usually use go-to subs for that sort of thing with G91 moves, but this technique seems like it is a good tool to have in the box of tools to use. I've heard some folks get wound up about mixing G90 & G91 but the fella that taught me G-code basics 30 years ago used both routinely without thinking much about it.

[lcmac]

You guys are like free school. Thanks for all the info

[iliandimitrov]

These examples are very helpfull indeed, thank you!

[somethingelse]

I kept having a 1 in 100 intermittent tool change issue where the machine would throw tools randomly against the walls, fixture, parts, etc. Maintenance wouldn't believe me--they'd watch it do ten tool changes and walk away. So then the machine would throw a drill randomly, nobody would notice, then try to bore a non existent hole, and have a cascading effect of tool destruction and scrap material. I eventually wrote a while loop that would do a continuous (user specified) loop of tool changes to prove I wasn't crazy. Well it worked, but it blew the thermal breaker on the ATC system almost immediately and I just about shit myself thinking I destroyed the machine. Lucky it just took a hard reset and was fine. I added a G04 dwell between tool changes before I showed off my fancy macro to anyone. Be careful, and always test your code with a variety of inputs.

[---MarcosVanzuita---]

Muito shoy este tutorial de repetição do Parabéns!👏👍

[shaunybonny]

Is this kind of stuff even needed with modern CAM software?

[KoenBrader]

Why do you count down? Isn’t there a “less than” or “less than or equal” ann increment to that?

[Bagginsess]

I wonder why the programming language enigneers didn't use "<=" for GT or "=>" for "LT" like in other programming languages.