gSender default

How to get gSender to default to inches instead of mm?

@wdashley - First of all welcome to the forum. Plenty of good people willing to help out.

If you click on the gear in the upper right corner it will display all of the setting options. The first screen is the general screen where you select inches (G20) or milimeters (G21). This is permanent until you change it. Enjoy and have fun.

I have the G20 ticked, but when you type command $G it list the default as G21

@wdashley - If I am not mistaken, and somebody more knowledgeable correct me please, GRBL converts inch commands to milimeter commands while processing/parsing before sending to the cnc. The $G command simply shows parsing parameters I believe. The general settings change the way your gcode is shown in the visualizer and may tell GRBL that the gcode needs converting from inches to milimeters. Hopefully this is correct. If not I’m sure someone will jump in and explain it to both of us.

Ok thanks for info. waiting to see if anybody has anything different to say.


You’re conflating two sets of units - the g-code modals and application preferences.

gSender will let you choose to display everything in the application in your preferred units - metric or imperial. That means anything that that is reported, from visualizer to DRO etc., will be in that units regardless of the modal of the file.

The GRBL firmware itself has it’s own unit modal which determines how it calculates cutting movements - that’s what you’re seeing when you press $G. It defaults to G21 (MM) always on startup since MM is the more standard unit worldwide.

You should never really have to worry about the GRBL firmware modal because if you’re running a tool path the value will either always be the default state (G21) or the modal that the program you’re running tells it to be (G20 or G21) based on the postprocessor used.

Hope that clarifies.



@KGN - Thanks Kevin. That’s what I was trying to say but your explanation is obviously better than mine. Appreciate you stepping in.

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