Weird XY movement with eShapeoko

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Posts: 2
Joined: Sat Feb 03, 2018 3:49 pm

Weird XY movement with eShapeoko

Post by roli » Sat Feb 03, 2018 8:19 pm

Hi! So recently I assembled my eShpaeoko v1.5 machine and I was finally ready to actually try and make something. So I began with a dry run of some simple design that I made. But when I ran the gcode the machine started behaving completely weird - it ended in a totally weird position.

So I downloaded the Shapeoko Hello World gcode from here:

Ran my machine and ended up with this (it drifted off paper eventually):
IMG_0090.JPG (168.45 KiB) Viewed 982 times
It began in the upper right corner and drifted towards the left bottom corner. I edited out a few other tries that I did, so ignore the artifacts.

If I use jog commands 10mm forward means 10mm forward. Similarly for other directions. So individually it goes where I want it to go. Except one thing... bCNC has move diagonal buttons. Three of them move the machine in the same direction - which of course shouldn't happen. -X +Y, -X -Y and +X -Y all move the machine in the same direction - which is -X -Y. Moving it to +X +Y works just fine on the other hand.

I am using GRBL 1.1 on one of those cheap Arduino CNC shields from ebay with A4988 stepper drivers with 1/16th stepping. The motors are Nema 23s ran from 24V. I did try flashing GRBL 0.9j as well, but it didn't change anything. And I did try universal gcode sender instead of bCNC as well.

Here are my GRBL settings:

Code: Select all

$0 Step pulse time [us] 10
$1 Step idle delay [ms] 25
$2 Step port invert [mask] 0
$3 Direction port invert [mask] 0
$4 Step enable invert 0
$5 Limit pins invert 0
$6 Probe pin invert 0
$10 Status report [mask] 1
$11 Junction deviation [mm] 0.010
$12 Arc tolerance [mm] 0.002
$13 Report inches 0
$20 Soft limits 0
$21 Hard limits 1
$22 Homing cycle 0
$23 Homing direction invert [mask] 0
$24 Homing feed [mm/min] 25.000
$25 Homing seek [mm/min] 500.000
$26 Homing debounce [ms] 250
$27 Homing pull-off [mm] 1.000
$30 Max spindle speed [RPM] 1000
$31 Min spindle speed [RPM] 0
$32 Laser mode enable 0
$100 X steps/mm 80.100
$101 Y steps/mm 80.100
$102 Z steps/mm 1646.800
$110 X max rate [mm/min] 5000.000
$111 Y max rate [mm/min] 5000.000
$112 Z max rate [mm/min] 300.000
$120 X acceleration [mm/sec2] 100.000
$121 Y acceleration [mm/sec2] 100.000
$122 Z acceleration [mm/sec2] 10.000
$130 X max travel [mm] 750.000
$131 Y max travel [mm] 1000.000
$132 Z max travel [mm] 200.000

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Joined: Mon Apr 09, 2012 6:11 pm
Location: Pennsylvania --- south of the Turnpike, East of US-15

Re: Weird XY movement with eShapeoko

Post by WillAdams » Mon Feb 05, 2018 1:54 pm

That looks as if you may be having overheating of the stepper drivers --- add a fan.

Also verify all the wiring and ensure that it all has continuity throughout the entire range of motion.
Shapeoko 3XL #0006 w/ Carbide Compact Router w/0.125″ and ¼″ Carbide 3D precision collets

Posts: 2
Joined: Sat Feb 03, 2018 3:49 pm

Re: Weird XY movement with eShapeoko

Post by roli » Tue Feb 06, 2018 6:22 am

A very helpful person over on Reddit pointed me in the right direction... my XDIR and YDIR pins were shorted together. I had a small solder bridge connecting the two and removing that bridge solved the issue.

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