FluidNC WebUI

I am a bit confused by the WebUI in Fluid NC and there is almost zero documentation that I can find. I use it and it works, but there I few things that I just don’t get. Here is the tablet interface:

At the top there is a G54 label. I understand that G54 is a work offset, but I don’t understand what it means in this context. I tried entering a value by clicking the X button and it moved very quickly to somewhere I did not expect, and I have not tried it since. I thought it would allow me to enter a specific coordinate and go there, which would be useful, but it did not do what I thought it would and now I am a bit gun shy. I am also not sure where you set the rapid speed for this function.
Below this section there is a G90 label. This is for absolute positioning. But it is above the jogging buttons, which in my mind are relative positioning. Am I missing something?
Below that there are two MDI buttons with GCODE command text boxes. I had to look up MDI: Manual Data Input. OK, I get it, but why are there two?
Lastly, is there a way to home individual axis in the tablet screen aside from entering the GCODE command? I have been homing from the Dashboard screen and then going to the tablet screen to jog into place before starting a job. I see in the menu there is a “Homing” command, but when I tried that, my z axis went straight up.
I am hoping to get some more information so I don’t have to have my hand on the kill switch every time I try something new in the GUI.

The repo for the webui is here if you want to ask questions that are not covered in the docs:

My understanding from reading Discord, etc. is the Tablet mode is a UI that Mitch added for himself because of the way he uses his machine, so it’s not likely to be super well documented.

I use it sparingly to jog bigger moves than is allowed on the main page, but generally I stay away from that page, as the main page has pretty much everything I need


The only thing I use the table side for is to visualize my gcode.

The regular interface is where we have always operated. The fluid guys are strict workspace users…we never really have been here.

I feel like this is a better place to ask questions. The discord users do things a bit different than we do.

If you want specific answer we can do that but in general for most jobs I see no need to complicate things with more workspaces just because it is the “proper” way people used to work.

Agreed. Only been on it a few days now with cnc but not once have I used tablet mode. If I want to make a big move I just type it in the terminal. G0 X450 Y800 F1000 moves mine to the center of my table for instance. Just be careful. Pay attention to where it is and what it says its at. It will retain the last spot you set zero even after a home. So adjust your gcode accordingly lol

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Took me a day or two to find the Probe tab. Handy when just messing around.
Hamburger icon upper right, preferences, in the GRBL panel–> Show Probe panel.

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How did you get the Probe tab to show up next to the override and spindle.


Try this one.

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Thank you for the obvious on his post. I was frustrated over some setup issue and completely swooshed by that.

About ready to fire up the LR3 I built and trying to figure out the jackpot.


No worries, I do it all the time!

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Still learning. What would you expect to happen if you enter G1 x500 F2000 into the gcode field after jogging? I thought it would keep the same settings as the jog, but it moved beyond the 580mm limit of my machine (I started at 0,0). Do I need to enter G21; G90; G94; G92 x0 y0; before the G1, or is something else going on?

The machine boots into G90 mode, Commands and Settings | Wiki.js


That is move to the right 500mm.

If you want to get to a specific location you can go into G91 mode first, or look at the current location and move as much more as needed.

I may have just homed as it was at home position. It moved right more than 580mm (limits of my machine).

Can’t you run G0 X500 F2000 and no matter where it’s at it will move to X500?

The only way that happens is if your steps per mm are wrong.

Only in G91 mode.

That’s what I thought, but something else is up. I had previously jogged by press 100mm 5 times and 10mm 8 times. I was looking for a quicker way, so I tried the gcode command. Steps are fine in jogging. I will play with it some more, maybe it was in absolute mode and I was not at 0,0. Maybe units were wrong? But it definitely moved more than 500mm and I didn’t intentionally change units or anything else. I was just surprised by it so wondering if I need to make sure to do G21and G90 prior to G1.

?? G91 is relative mode. With G90, it should move to 500,0 from your origin. That is one reason this is perplexing to me. If it was set in relative move, it should have only moved 500mm to the right. If it was in absolute mode, the origin would have to be negative to move past 500, 0. I was just wondering if in startup or when jogging it was doing something to the coordinate system or units that would cause this. When I get some time on my machine, I will play with this some more to try to understand what is going on.

I am not clear on this. You did this one time and it went wrong?

Try it a few more times, reboot try again. If it is a repeatable mistake it is easy to figure out a one off could just be a mistake.

Twice, then I was gun shy because it did not make sense to me and I don’t like hitting the limit and skipping steps. I will try again, hopefully tonight and see what I can figure out.

Right sorry I am all backwards.

So instead of 500 try 10. If there is an issue we need to figure it out but this should not be an issue or I am sure we would hear about it a lot more. I even use it in my starting gcode and have no issues…but might have some other stuff in there as well.

I tested this again and still seeing the issue.
Here is the command log. I deleted the lines in the middle to keep this shorter(lines with … are where I removed them). I homed, then jogged 100 in Y and 100 in X. Then did G1 X10 and it moved 51.7mm. Ideas?

$J=G91 G21 F1000 Y100

$J=G91 G21 F1000 X100

G1 x10 f2000
[GC:G1 G54 G17 G21 G90 G94 M5 M9 T0 F2000 S0]