Ask Grbl CNC questions here.

Hi Richard ,

I'm a Newbie here too , but this sound like you are hitting one of the extents limits of the workspace. What have you got them set to ?

Regards

Dave

 

Hi Dave
thanks, I am going through the settings I may have set my limits to short and stopping the plunge depth.
the thing that stumps me is the' open door' error ,I don't have a door. And the cut is within my work piece limits
Richard

 

Hi Richard
I'm currently getting to grips with the settings too , especially as I've just swapped out my Arduino.
Are you running on a Uno , or Mega ?
Feel free to post your G-code ,and I'll run it though my setup .
I agree the door error is confusing, though I find the errors a little confusing at times anyway.
Regards

Dave

Safety Door seems to be disabled by default in config.h
// #define ENABLE_SAFETY_DOOR_INPUT_PIN // Default disabled. Uncomment to enable.

 

hi Dave
thanks I will upload the g code
Richard

 

Sorry I don't understand Arduino.and Uno , or Mega
Richard

 

I've just successfully run your G-gcode , "cutting air" and it seems to behave fine. ( once I'd changed all the Z4.0 to Z0.0 , as I've only got about 2" of Z travel at the moment .

I have had hard-limits ($21=1) set today and I've been rewiring various things this has been giving me frequent hard limit errors I disabled this ($21=0) when I ran your G-code.


Arduino / Uno /Mega is the Microcontroller hardware grbl is running on.

Regards

Dave

 

Hi Dave
Thanks, I have changed the setting for Z and in openScam it is looking good. As it is late here I will try and run a cut, fingers crossed for a good result
once again thanks Dave
regards
Richard

 

Hi Dave
Thanks for your help all went well and have made my first cut.
Regards
Richard

 

Thank you David for your help.
regards
Richard

 

Good to hear

Regards

Dave

 

Ok , so I've implemented an interrupt based serial write and read and working on rx1/tx1 on the mega and have "tested" by writing messages to the serial port , and echoing anything that it receives .

I'm still waiting for my VFD to arrive , and Its delayed . My intention is to send suitable commands to the VFD from the spindle_init spindle_stop and spindle sync commands, though I noticed the pwm is also set continually during moves from the spindle_set_speed which is called stepper ISR.
Can anyone explain to me why this is ? for my case, I think this is unnecessary , but I would like to understand the intentions of the original author.

On another point are there any test within grbl to verify the performance of the stepper routines , to check that I'm not slowing those down,and if so by how much ?

Best Regards

Dave

 

That makes perfect sense to me now.

Many Thanks

Dave

 

Hello, I like many of you have built a CNC machine in hopes of ultimate diy heaven. Unfortunately my build comes to an abrupt halt when my machine will not fulfill its function properly. The problem arises when I tell the machine to cut a 30 mil square and it cuts a 29.8 mil square. With that being said I have done at the very least probably 40 distance travel tests up to 400 mils and they are all spot on. Please help

 

Well when I cut the square I was making sure not to have any flex in the machine( or as least as possible). I cut the square at a depth of .04 per pass at 40 mil feed rate and had a brand new enpoint 1/8 single flute up spiral bit. When I first cut the square it was worse so I checked everything and find the wheels to be too tight. The machine is double belted for extra strength and is mounted directly to a torsion box for bed accuracy. I plan on doing wood inlay work for a side job but I won't be able to if the best that the machine can handle is .2 mils off. I would like to mention that the square is actually square but is under sized in all directions. Could it be an off set from fusion 360 or an undersized smoothing operation. Update: I checked the size on the end mil. .117 or approximately 3mm at the cutter head. That only means the problem is worse than I thought.

 

Can you please reverberate run-out, tool, etc. I have a Makita trim router as my spindle and it is attached using the quick and dirty method but plan on making better mounts out of 1/2 in. hdpe. But I couldn't see any other possible problems other than possible cam inaccuracy as I am still learning the lingo as well as fusion 360 or machine inaccuracy ( belt stretch, flex, etc.)

 

Hi, I'm having a heck of a time. I've been mostly successful building a laser engraver (A simple XY laser engraver/cutter).

I've set up GRBL 1.1f (after a lot of trial and error) and got things working. I can jog both axis, I can import and run g-code, I can even engrave stuff successfully.

What I can't do is home the thing. I have my limit switches set to NO. I've tested each with a multi-meter. I set $5=1. If I jog or have gcode that hits one of the switches everything stops correctly (which didn't always happen). When I send $H I can hear the steppers power on (I have $1=25 and not 255 for no good reason).

Every time I power it on, it starts in an alarm state (product of $22 ???).

When I sent $H I get the following:

$H < ALARM:9
ok
Grbl 1.1f ['$' for help]
[MSG:'$H'|'$X' to unlock]
S6705 < error:9
$X < [MSG:Caution: Unlocked]
ok
S6705 < ok

I am really new at this and it could be something simple I missed... I hope it is. If someone could suggest what else I can look into, I'd greatly appreciate it.

Below are some of my settings (let me know if there is something relevant I didn't include).

$5=1
$6=0
$10=3
$20=0
$21=1
$22=1
$23=0
$24=50.000
$25=635.000
$26=250
$27=5.000

Thank you so much for any help.

 

I'm only a Newbie, but this sounds like you need $5=0 , That's what I have on my 3 axis router
and I'm sure my limit switches are normally open,

I think if you have the limits inverted it will try and drive a little way to move away from the microswitch and then rehome slowly. if it cannot move away in a short distance then I'd imagine it would set an alarm

Regards

Dave

 

Thank you Sonny. I really appreciate you taking the time to respond to my question. I'll dig into this more, thanks for pointing me in a new direction.

Right now, it's not moving at all before the error.

By travel settings, is there a specific setting? I only see $24 and $25, but that looks like it is only the speed.

I didn't change $130, $131, or $132 because the wiki said "this sets the maximum travel from end to end for each axis in mm. This is only useful if you have soft limits (and homing) enabled, as this is only used by Grbl's soft limit feature to check if you have exceeded your machine limits with a motion command."

But I'll try that when I get home.

Thanks again, time is valuable and I appreciate you sharing some of yours.

d

 

Thanks Dave! Any help is good help! Unfortunately, that doesn't seem to be my problem. I think I have it correctly set for normally open switches. However, to be safe, I also tried it the other way... But thanks again.

 

Have you disabled the "Homing for the Z Axis" ? I'm pretty sure I couldn't get homing to work properly until I had all three axes
connected ( I first connected up grbl when I'd only build the Z & X axes )
Regards

Dave

 

Oh wow! I can't wait to get home, that makes so much sense it might actually work!!! It tries to home the z axis first! Thank you!!! Wow. I don't want to jinx myself, but I've been messing with this for a week!

 

I'm currently upgrading my spindle , so I can play

I've disconnected the z axis and If I home , I get

$H
ALARM:9
$G
ok
Grbl 1.1e_dah26/2 ['$' for help]
[MSG:'$H'|'$X' to unlock]

If I edit config.h about line 105

from

#define HOMING_CYCLE_0 (1<<Z_AXIS) // REQUIRED: First move Z to clear workspace.
#define HOMING_CYCLE_1 ((1<<X_AXIS)|(1<<Y_AXIS)) // OPTIONAL: Then move X,Y at the same time.

to

#define HOMING_CYCLE_0 ((1<<X_AXIS)|(1<<Y_AXIS))

effectively comment lines 105 and 106 , and uncomment line 110 that should work .It did for me .

Regards

Dave