After breaking 2x ⅛ router bits I think I might have found another bug. Should have started with a test cut without a bit first… but I got overconfident after one successful cut.
When I start a cut the z axis immediately plunges all the way down to the motors and then starts to travel to the starting point of the cut. At first I thought this was a mistake in my gcode as I have run into that before but I double checked all my CAM settings in fusion 360 and all looks good. Then I noticed this was happening really before the start position of my cut so I am guessing this is something on the M4 side instead. Also noticed it does the same thing at the end of the cut when it travels back to home.
Ran through this several times thinking I got the “zeroing out” the z axis wrong and maybe I am following the wrong procedure so here is what I have been doing. Here is what I have been doing:
Power On M4
Move Z Axis all the way to bottom out on motors, Zero Z Axis Button
Retract, Extend, Apply Tension
Move Z-Axis Up to have bit in line with sled or when no bit just move it up 1 in (tried different heights but shouldn’t matter) to simulate a bit inline with shed
Define Home for Z Axis
Press Play
Noticed some other issues with how the Pause, Stop Operation Buttons work while working through these tests:
Noticed that when I pause a cut I can’t jog the sled at all and have no way to cancel the cut without hitting the stop button that then requires the whole power cycle and start up dance (Retract, Extend, Apply Tension). Very annoying and time consuming when trying to troubleshoot.
Noticed on one occasion where I put in a much larger z axis value to go up and wanted to stop this that when I hit the Stop button it did not stop the z axis movement even though I got the Emergency stop message.
(0125 Finish Contour 2)
T2
S16000 M3
G17 G90 G94
G54
G0 X5.383 Y4.1466 ← Move to starting location, no Z move commanded
Z0.8
G1 Z0.2 F80
Z0.1125 F40
This sounds 100% correct.
I agree that this looks like it could be a bug. When I was adding the “Zero Z” button I was having a bunch of issues getting to to behave correctly because FluidNC stores the machine position in a whole bunch of different places and they all need to be set propperly when it is reset so maybe I missed something. I will dig into it.
I completely agree, the play stop pause button behavior right now is frustrating and annoying. That is on the Todo list for sure!
Hi, was this issue ever resolved? I’ve been running into the same problem very intermittently and am curious if this a me problem or a SW bug? Gcode looks correct. I raise the z axis above the stock, press play, it plunges and moves to the starting position. And same at the end of the cut
Hi, was this issue ever resolved? I¢ve been running into the same problem very
intermittently and am curious if this a me problem or a SW bug? Gcode looks
correct. I raise the z axis above the stock, press play, it plunges and moves
to the starting position. And same at the end of the cut
do you set home after you lift the Z axis above the stock and before you hit
play?
Hi David, nope, I home the z axis with the bit at stock level and then raise it up.
EDIT:
I tried a dry run with the same gcode/no bit/newly zeroed Z and it seemed to work. Router went up, moved to start position, down and followed the tool path. I shut down the machine, put a bit in, did the rehang dance, re zeroed, moved the z axis up, and clicked play. It immediately plunged and drove to start. Is this possibly a bug in the z-zeroing workflow depending on order of operations?
Issue hasn’t been resolved yet! I’m hoping it gets address this week before I get back to my machine this weekend. I have so many projects lined up and stuck at this roadblock
It happens every time I go through my start up process that I outlined above. I’ve tried different code files to see if it’s an issue with tool path settings and no luck.
I can take a video of going through the start up process if that helps. I’ve been noodling of what else I could try on my end as it doesn’t seem to be a wide spread issue but I’ve run out of ideas.
one thing that I see is that you have Z commands on bare lines. some CNC machines accept that, but I believe that grbl/fluidNC requires G0 or G1 and may be doing something odd as a result of the bare Z on a line
Also, it’s possible that the G54 could be changing your coordinate system in ways that you are not expecting
what type of CNC machine are you telling your CAM program that you have?
Using Fusion 360 and exporting as GRBL which was what I worked for the M2 I had before the M4. Have not changed any of the default configurations here tin the post properties and I know next to nothing on the specifics of code so this could totally be the source of the issues. Any insight based on this?
That’s the process. I totally understand it’s hard to lend support when you can’t experience it firsthand. That is why I can at least video how I went about it to see if there is something there.
Curious to explore the how Fusion 360 exports the G Code could affect this that dlang pointed out. Any insight here would be great but I will do my own research as I should probably understand g code better in general.
Here is the video. Sorry for the quality at times. Was by myself today and need 2 hands for different parts of the process as Im sure you understand haha.
I am including the logs as well and nc file I used for this test to help as well.
Ran into an issue where the file showed as not centred on the workspace which it normally does but didn’t affect cutting. Not too worried about that right now.
P.S. Very happy to see that the Stop Button no longer Hard Stops the machine so I can now jog it around and not have to do the whole start up process again
As always appreciate the assistance with figuring out this elusive issue!
I’ve also run into the issue intermittently running Fusion 360 and exporting as GRBL. It’s been hard to duplicate though and my process looks the same as @NickyD … I had run 10 files today with no problems, got a 15 mm error and as part of my attempted recovery cut, the plunge happened again twice in a row.
