Canno use the CNC after installing limit switches

newage · March 20, 2022, 8:50am

Hello!
I’ve got one of those CNC engraver combined with Laser module. The original did not have limit switches so I installed them additionally and connected them to the controller. It seems they are working, because now I can home it without crashing.
However now I cannot engrave anything, when I start engraving I get a message:

Starting stream

ALARM:2
G-code motion target exceeds machine travel. Machine position safely retained. Alarm may be unlocked. (Right-click the ‘Devices’ button to reset the connection)
On or near line 2:
Stream completed in 0:00
[MSG:Reset to continue]
ok

Grbl 1.1f [’$’ for help]

CNC4030|1.02|211109

[MSG:’$H’|’$X’ to unlock]

[MSG:Caution: Unlocked]

ok

berainlb · March 20, 2022, 9:23am

A couple of things to look at:

Make sure that your GRBL settings $130, $131, $132 – [X,Y,Z] Max travel in mm is setup correctly.
Suggest you work in Absolute Coords mode in Start From: setting in Laser window until you’re very familiar with the laser.

That should avoid most of these situations going forward.

The other possibility is that your coordinates system is not getting properly setup after homing.

Can you confirm to what corner your laser homes?
What are the coordinates of the laser after homing?

Can you run these commands in Console after homing:

$$
$#
?

newage · March 20, 2022, 5:23pm

Hi!
This is how it is homed:

here’s the result of $$:

$$

$0=10
$1=25
$2=0
$3=0
$4=0
$5=0
$6=0
$10=1
$11=0.010
$12=0.002
$13=0
$20=1
$21=1
$22=1
$23=0
$24=25.000
$25=500.000
$26=250
$27=1.000
$30=1000
$31=0
$32=0
$100=800.000
$101=800.000
$102=800.000
$110=1200.000
$111=1200.000
$112=1000.000
$120=50.000
$121=50.000
$122=20.000
$130=200.000
$131=200.000
$132=100.000

$#

[G54:-300.000,-150.000,0.000]
[G55:0.000,0.000,0.000]
[G56:0.000,0.000,0.000]
[G57:0.000,0.000,0.000]
[G58:0.000,0.000,0.000]
[G59:0.000,0.000,0.000]
[G28:0.000,0.000,0.000]
[G30:0.000,0.000,0.000]
[G92:0.000,0.000,0.000]
[TLO:0.000]
[PRB:0.000,0.000,0.000:0]

?

<Idle|MPos:-1.000,-1.000,-1.000|FS:0,0|WCO:-300.000,-150.000,0.000>

ok

berainlb · March 20, 2022, 5:38pm

Did you set this deliberately? It doesn’t seem to be causing a problem at the moment. You may have set this up for CNC operation.

Can you confirm what your actual work area is for the laser? Is it actually 200x200x100mm?

You’re starting in negative coordinates. I think you may be able to fix this by adjusting your pull-off.

$27=2

You’re not on laser mode which you almost certainly want:

$32=1

Can you try making those adjustments, re-run a homing cycle, and then rerun ? command after homing?

newage · March 20, 2022, 6:41pm

Hi!
I must have done something wrong. I installed the default registry backup and now it is homing at far right/far front position. Here is again:
$$

$0=10
$1=25
$2=0
$3=0
$4=0
$5=0
$6=0
$10=1
$11=0.010
$12=0.002
$13=0
$20=0
$21=1
$22=1
$23=0
$24=25.000
$25=500.000
$26=250
$27=1.000
$30=997
$31=0
$32=1
$100=800.000
$101=800.000
$102=800.000
$110=1000.000
$111=1000.000
$112=1000.000
$120=50.000
$121=50.000
$122=20.000
$130=200.000
$131=200.000
$132=200.000

$#
[G54:-300.000,-150.000,0.000]
[G55:0.000,0.000,0.000]
[G56:0.000,0.000,0.000]
[G57:0.000,0.000,0.000]
[G58:0.000,0.000,0.000]
[G59:0.000,0.000,0.000]
[G28:0.000,0.000,0.000]
[G30:0.000,0.000,0.000]
[G92:0.000,0.000,0.000]
[TLO:0.000]
[PRB:0.000,0.000,0.000:0]

?
<Idle|MPos:-1.000,-1.000,-1.000|FS:0,0|WCO:-300.000,-150.000,0.000>

However when I type G0 X0 Y0 it homes into the old position as shown in the photo.
It is very confusing

berainlb · March 20, 2022, 6:51pm

Did you make a bunch of arbitrary changes?

Let’s fix these:

$20=1
$30=1000
$110=1200
$111=1200
$132=100

Also, you didn’t change your pull-off.

$27=2

Please fix and rerun.

Also, what is your actual work size please?

newage · March 20, 2022, 6:51pm

Pull Off would not change:
$27=2
error:3
Grbl ‘$’ system command was not recognized or supported.

berainlb · March 20, 2022, 6:52pm

Nothing in the GRBL changes should have changed homing direction. So not sure what you’re seeing. Also, G0 is not a homing command.

berainlb · March 20, 2022, 6:53pm

Odd.

Can you try this:

$27=2.000

newage · March 20, 2022, 6:57pm

$27=2.000

error:3

Grbl ‘$’ system command was not recognized or supported.

What could be wrong?! Could be that I connected the switches wrong or something else, since the controller comes with no instructions.

berainlb · March 20, 2022, 7:00pm

Vendor may be preventing changes to that parameter.

Anyhow, starting from -1,-1 shouldn’t necessarily cause the error that you initially getting. I don’t think.

Under what circumstances did you get the error message?

And can you confirm your work area please?

newage · March 20, 2022, 7:03pm

Here’s the machine settings menu:

according to specifications:
Effective Working Travel: 300(X)x180(Y)x45(Z)mm

berainlb · March 20, 2022, 7:20pm

Change these to:

$130=300
$131=180
$132=45

In Device Settings change work area to 300x180.

Rerun your original test and see if you still get the same error.

newage · March 20, 2022, 7:38pm

It seems to be working now.
Thank you for your time and efforts to help me! I did not expect it to be so complicated.
I will write some info later, when I start using it.

newage · March 21, 2022, 12:47pm

Now I have the following problem:
when I try to cut a simple circle I get error:
ALARM:2
G-code motion target exceeds machine travel. Machine position safely retained. Alarm may be unlocked. (Right-click the ‘Devices’ button to reset the connection)

On or near line 4:
Job halted
Stream completed in 0:00
[MSG:Reset to continue]
ok
Grbl 1.1f [’$’ for help]
CNC4030|1.02|211109
[MSG:’$H’|’$X’ to unlock]

[MSG:Caution: Unlocked]

ok

What does it mean?

berainlb · March 21, 2022, 2:11pm

Are you using Absolute Coords? If not, suggest you do so.

This occurs if the machine believes you are about to go beyond the borders of the laser and prevented a crash.

newage · March 21, 2022, 3:28pm

No, I tried to use “current position”. Isn’t it possible to use both?

berainlb · March 21, 2022, 3:39pm

It’s possible but you need to ensure you’re not running out the boundary. This means no manual moves after homing. Only jogging. And you need to make sure that the burn boundary still doesn’t go beyond the working area.

If you don’t want to deal with the error message you can disable soft-limits with $20=1 but you diminish some of the value in having homing switches and risk crashing.

newage · March 21, 2022, 5:11pm

Is it possible NOT TO home the Z (the laser) because I lose the focus and have to re-adjust it every time?

berainlb · March 21, 2022, 6:22pm

Only if you get a different firmware.

But why do you lose focus? Can you not set focus based on material thickness? Or specific a z offset for the layer.