New build, strange issue. Not sure where to go.

[rowka]

I've just finished a new build of a CNC router and I'm having some issues. I don't know the source of the issue, so I'm reaching out to the various HW and SW vendors I used to see if anyone has any ideas.
Signal flow is UCCNC -> CNC Drive UC300ETH-5LPT ethernet motion controller -> CNCDrive UCBB breakout board -> four G201x (x, y with B slave, and z). My lead screws are 5 start/0.5 in/turn. The math tells me 200 steps per revolution x 10 micro steps per step x 2 revolutions per inch = 4000 steps per inch of travel. So I set all the axis up at 4000 steps per inch. I have B slaved to Y with the same tuning settings. 100 ipm max speed, acceleration I’ve played with different values between 3 and 30.
So I’m jogging around, checking homing and what not. The gantry starts racking horribly. I double check the tuning and everything looks right.
Power it down and get it squarish. Nothing is binding. The lead screws turn easily when the motors are not energized.
Okay, I’ll deal with that later. Start working on the X axis. 4000 steps per inch seems way off. I run the calibration routine and come up with 7400 and change. But here’s the thing. If I go X +10 inches it’s fine. Now if I go X -10 inches, it travels closer to 12 inches. I double check the indicators on the couplings and nothing is slipping. I double check for binding and it’s fine.
Thoughts?

[dezsoe]

Try to invert the step signal (flip active low). Also, do not use 400 kHz kernel frequency: the G201x manual sais max. 300 kHz.

[rowka]

Step signal is set to Active Low (if I set to active high, the motor just sits and squeals).
I'm using 100 kHz kernel frequency.

I have been working on my physical X axis only, but have swapped the leads from the X motor to the other drives with the same results.
Calibrating in the positive direction produces positive direction accuracy, but negative direction overshoot. Along with a much greater than expected steps per unit setting.

I had a phone call with the folks at GeckoDrive to trouble shoot the G201x dirves. We are 99.9% convinced the trouble is not with the motor drives.

Don't know what to do next.

[Robertspark]

is the step and direction signals the right way around wiring wise and port / pin references?

are you using the right port as there are two different port types on the uc300eth?

can you upload your profile and some wiring photos ?

I can water divine but never been good with crystal balls or magic wands.

[dezsoe]

You can also skip the UCBB and connect directly to the UC300, because the inputs on the Gecko are optoisolated.

[rowka]

Port 2 is the standard type, and port 1 is the extended type (which I'll admit gets confusing when 300ETH-Port 1 connects to UCBB CN2 and 300ETH-Port 2 connects to UCBB CN1)

Step and Direction all on port 2
X s08
X d07

Y s04
Y d03

B s02
B d01

Z s06
Z d05

Step and direction pairs are shielded and grounded at the driver end. The stepper motor cables are likewise shielded and grounded.

Profile attached.

[Robertspark]

UCBB, pin 10 common.

what is the white wire wired up to?

this needs to be wired up to the 5V (+) connection. Is that how you have wired it?

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the G201x, it looks like all the dip switches are set off, is this correct? (bit difficult to see the photo close up).

how are you setting the motor current?

https://www.geckodrive.com/support/g201 ... rev-6.html

(I know I'm probably asking daft questions, but only you are sat with the machine that does not work right so sometimes the daft questions need to be asked to try to find the problem).

_____________________

I'll take a look at your profile later

[Robertspark]

It looks like you are using Gerry's 2017 screenset. (I don't think there is anything wrong with this, but would it be possible for you to try to load the default uccnc profile and set it up with the ports and pins assignments for Step and direction + estop just to see if maybe there is a problem somewhere.

you have a uc300eth, with a UCBB, and gecko G201X drives. It probably will help cncDrive to diagnose your problem if you get everything setup on the default screenset first before trying a customised one

I am not sure what version of UCCNC you are running, but please note that the 2017 screenset requires:

UCCNC version 1.2047 to 1.2049

(I cannot tell what version of uccnc you are running from looking at your RAW profile, but I may have simply just missed it).

[rowka]

White wire to 10 common on the g201x is the +5v from the UCBB
The switches are not visible from the photo. They are set to 4.2 amps (motor rating), standby enabled, nema 34 disabled (confirmed with Marcus at GeckoDrive).
I’m running the version 1.2049. I’ll load up the default screenset and see if that changes anything.

[laki]

How did you connect the charge pump circuit?
From your profile I see you are using both outputs.