GBRL refuses to home. - $H

Discussion about the arduino based g-code interpreter, grbl
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VT91
Posts: 69
Joined: Tue May 28, 2013 6:47 pm

GBRL refuses to home. - $H

Post by VT91 » Thu Sep 19, 2013 3:59 am

Hello.
I tried to change some settings of GBRL 0.9 to make it home the right way.

Code: Select all

**** Connected to COM10 @ 9600 baud ****

Grbl 0.9a ['$' for help]
['$H'|'$X' to unlock]
>>> $$
$0=10.936 (x, step/mm)
$1=10.936 (y, step/mm)
$2=320.000 (z, step/mm)
$3=500.000 (x v_max, mm/min)
$4=500.000 (y v_max, mm/min)
$5=500.000 (z v_max, mm/min)
$6=10.000 (x accel, mm/sec^2)
$7=10.000 (y accel, mm/sec^2)
$8=10.000 (z accel, mm/sec^2)
$9=10 (step pulse, usec)
$10=250.000 (default feed, mm/min)
$11=96 (step port invert mask, int:01100000)
$12=25 (step idle delay, msec)
$13=0.050 (junction deviation, mm)
$14=0.005 (arc tolerance, mm)
$15=3 (n-decimals, int)
$16=0 (report inches, bool)
$17=1 (auto start, bool)
$18=0 (invert step enable, bool)
$19=0 (hard limits, bool)
$20=1 (homing cycle, bool)
$21=0 (homing dir invert mask, int:00000000)
$22=2147483.648 (homing feed, mm/min)
$23=250.000 (homing seek, mm/min)
$24
Something happens and when I enter a $H command my machine holds all motors for an undetermined period of time instead of moving them.
Z axis is making a whispering sound but nothing is moving.

However I can JOG the machine manually with arrow keys and all motors work.
I tried to reinstal GBRL and XLoader froze and I am not sure if anything happened.
WHY?

Code: Select all

Grbl 0.9a ['$' for help]
['$H'|'$X' to unlock]
>>> $$
$0=10.936 (x, step/mm)
$1=10.936 (y, step/mm)
$2=320.000 (z, step/mm)
$3=500.000 (x v_max, mm/min)
$4=500.000 (y v_max, mm/min)
$5=500.000 (z v_max, mm/min)
$6=10.000 (x accel, mm/sec^2)
$7=10.000 (y accel, mm/sec^2)
$8=10.000 (z accel, mm/sec^2)
$9=10 (step pulse, usec)
$10=250.000 (default feed, mm/min)
$11=96 (step port invert mask, int:01100000)
$12=25 (step idle delay, msec)
$13=0.050 (junction deviation, mm)
$14=0.005 (arc tolerance, mm)
$15=3 (n-decimals, int)
$16=0 (report inches, bool)
$17=1 (auto start, bool)
$18=0 (invert step enable, bool)
$19=0 (hard limits, bool)
$20=1 (homing cycle, bool)
$21=128 (homing dir invert mask, int:10000000)
$22=2147483.648 (homing feed, mm/min)
$23=250.000 (homing seek, mm/min)
$24
Nothing moves during homing either.
There are 3 Normally Closed homing switches on my machine.

Thank you.
Vladimir T.

bjbsquared
Posts: 102
Joined: Mon Nov 26, 2012 10:48 am

Re: GBRL refuses to home. - $H

Post by bjbsquared » Thu Sep 19, 2013 10:22 am

This looks suspicious
$22=2147483.648 (homing feed, mm/min)
There are 3 Normally Closed homing switches on my machine.
Also I think that GRBL only works with normally OPEN switches. Having a closed switch is telling it not to move.
#1016 - 1M x 1M Y: Dual Motor Drive w/Looped Belts, X:Dual Rail with wlanfox blocks, Z: Stock, Spindle:DW660

twforeman
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Location: Minneapolis, MN
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Re: GBRL refuses to home. - $H

Post by twforeman » Thu Sep 19, 2013 1:25 pm

I also think you need to enable hard limits - $19=1 - for homing to work.
Ender 3 3D Printer
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cvoinescu
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Location: Camberley, UK
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Re: GBRL refuses to home. - $H

Post by cvoinescu » Thu Sep 19, 2013 6:20 pm

You definitely don't want to move 2.14 kilometers per minute while homing: that's 128 km/h, or 80 mph. That number looks like garbage in the config memory.

You can use NC limit/homing switches with GRBL if you want -- I'll explain how, if you have a good reason to do it that way. Normally, you just use NO.
Proud owner of ShapeOko #709, eShapeOko #0, and of store.amberspyglass.co.uk

VT91
Posts: 69
Joined: Tue May 28, 2013 6:47 pm

Re: GBRL refuses to home. - $H

Post by VT91 » Sat Sep 21, 2013 6:55 pm

bjbsquared wrote:This looks suspicious
$22=2147483.648 (homing feed, mm/min)
There are 3 Normally Closed homing switches on my machine.
Also I think that GRBL only works with normally OPEN switches. Having a closed switch is telling it not to move.
The machine works on NO switches by default. Or it just relies on the change of state and memorizes that.
I changed speed and things work a lot better now.

How would I save all those settings that come out of the driver when I enter "$$" command?
Is there any way of saving them into a text file and loading them all at once in case some problem happens or I have to buy a new driver?

VT91
Posts: 69
Joined: Tue May 28, 2013 6:47 pm

Re: GBRL refuses to home. - $H

Post by VT91 » Sat Sep 21, 2013 9:45 pm

How would I check if my machine resolution is right?

I cannot understand every line of G code that I read yet. So I tried to make my machine make a line of 100mm in X axis and in Y axis.
(Z has to travel somewhat to make a pencil that I placed in the chuck of a spindle to go up and down.)

This code should give a 1" circle but it seems not to be 1" at the end. More like 5/16". I want to work in millimeters though.

Code: Select all

M03
G17 G20 G90 G94 G54
G0 Z0.25
X-0.5 Y0.
Z0.1
G01 Z0. F5.
G02 X0. Y0.5 I0.5 J0. F2.5
X0.5 Y0. I0. J-0.5
X0. Y-0.5 I-0.5 J0.
X-0.5 Y0. I0. J0.5
G01 Z0.1 F5.
G00 X0. Y0. Z0.25
M02
My current settings:

Code: Select all

**** Connected to COM10 @ 9600 baud ****

Grbl 0.9a ['$' for help]
['$H'|'$X' to unlock]
>>> $$
$0=10.936 (x, step/mm)
$1=10.936 (y, step/mm)
$2=320.000 (z, step/mm)
$3=500.000 (x v_max, mm/min)
$4=500.000 (y v_max, mm/min)
$5=500.000 (z v_max, mm/min)
$6=10.000 (x accel, mm/sec^2)
$7=10.000 (y accel, mm/sec^2)
$8=10.000 (z accel, mm/sec^2)
$9=10 (step pulse, usec)
$10=250.000 (default feed, mm/min)
$11=96 (step port invert mask, int:01100000)
$12=25 (step idle delay, msec)
$13=0.050 (junction deviation, mm)
$14=0.005 (arc tolerance, mm)
$15=3 (n-decimals, int)
$16=0 (report inches, bool)
$17=1 (auto start, bool)
$18=0 (invert step enable, bool)
$19=0 (hard limits, bool)
$20=1 (homing cycle, bool)
$21=192 (homing dir invert mask, int:11000000)
$22=12.000 (homing feed, mm/min)
$23=8.000 (homing seek, mm/min)
$24=100 (homing debounce, msec)
$25=1.000 (homing pull-off, mm)
ok

WillAdams
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Re: GBRL refuses to home. - $H

Post by WillAdams » Sun Sep 22, 2013 12:20 am

Here's one way to do it:

Code: Select all

G17 (arcs on XY plane)
G21 (metric)
G90 (absolute distance)
F355 (set feed speed to 355mm/min)
G0 Z1 (lift spindle up 1mm)
G0 X0 Y-12.7 (move 1/2inch down)
G1 Z0 (lower spindle)
(clockwise arcs 1/4 of the way around)
G2 X-12.7 Y0 I0 J12.7
G2 X0 Y12.7 I12.7 J0
G2 X12.7 Y0 I0 J-12.7
G2 X0 Y-12.7 I-12.7 J0
G0 Z1 (lift spindle up 1mm)
G0 X0 Y0 (return home)
Shapeoko 3XL #0006 w/Makita RT0701 Router w/0.125″ and ¼″ Elaire precision collets
Nomad 883 Pro #596 (bamboo)

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