Comments on: Arduino CNC Shield V3.XX – Assembly Guide

By: Bertus Kruger

Bertus Kruger — Tue, 27 Oct 2015 17:47:27 +0000

This sounds like it could be the stepper motor wires being hooked up wrong. have a look at http://blog.protoneer.co.nz/stepper-motors-wiring-up-a-bipolar-stepper-motor/ Have you swapped out the stepper driver as another test?

By: Vicente Chazard

Vicente Chazard — Fri, 09 Oct 2015 12:08:12 +0000

Hi!

I’m complete noob in the Grbl word, but not in the Arduino one.
I am trying to connect a CDROM step motor, but can´t manage to have a smooth motion. Each time I send a command it moves but with a lot of hiccups, instead of a nice “ZZZZZZZZZ” noice, I get a “BrrZBrrZBrrZ”, and the motion is not clean.

I assume I might need some jumper somewhere and/or need to setup the Grbl with proper values.

Can anyone assist me?

By: Bertus Kruger

Bertus Kruger — Mon, 14 Sep 2015 09:34:59 +0000

yes… Normally Open switches with shielded cable and a properly grounded machine.

By: Aiden

Aiden — Fri, 11 Sep 2015 09:19:37 +0000

OK thanks, yep got the steppers to move correctly in each direction.
Next question is for the limit switches, is it the Common and Normally open pins on the micro-switches that connect to the end stops on the CNC shield V3?

By: Bertus Kruger

Bertus Kruger — Thu, 10 Sep 2015 02:32:12 +0000

Check the enable pins align on the board and the stepper driver.(EN)

By: Aiden

Aiden — Tue, 08 Sep 2015 13:06:13 +0000

Hi, I too am using Pololu DRV8825 drivers but I’m confused about which way round they are supposed to go in this CNC Shield V3 board.

Do they go with the variable resister nearest the bottom of the board (facing towards where it says ‘CNC Shield’) – like every picture I’ve seen of the A4988 drivers in situ, or should the variable resister be facing the top of the board (facing towards the ‘Reset’ side of the board) – this way would match the schematic on the Pololu website, and I have seen some pictures of this layout. Just checking because I don’t want to destroy my drivers!

By: Bertus Kruger

Bertus Kruger — Sun, 16 Aug 2015 05:22:32 +0000

With the default PWM settings enabled you need to run the S command to enable the spindle. From memory S is 0-1000 with S1000 being spindle at 100% power.

By: Tobi

Tobi — Fri, 14 Aug 2015 05:22:40 +0000

I´ve done so, but now i am not able to control my laser relay with M3/M5 anymore…

By: Bertus Kruger

Bertus Kruger — Thu, 06 Aug 2015 08:01:26 +0000

Hi. It if its a simple on/off laser all you have to do it to connect the laser enable pin to the spindle pin on the board. Arduino pins are low current and will not power a laser, so use some kind of relay or transistor to drive more power.

By: Bertus Kruger

Bertus Kruger — Thu, 06 Aug 2015 07:58:29 +0000

Hi Jay, The Pololu A4988 driver only support up to 1/16th micro stepping. https://www.pololu.com/product/1182

By: Hung Tran

Hung Tran — Tue, 04 Aug 2015 17:10:06 +0000

hello Bertus Kruger. i’am using cnc shield + arduino + laser. but i don’t know how to connect laser into cnc shield.
Can you help me?
(

By: Jay

Jay — Tue, 04 Aug 2015 07:39:02 +0000

Hi Bertus thank you for the information here.

I am facing a strange problem with my driver . My Cnc shield is Ver3.03 and driver is A4988 set for Nema17 for shapeoko2. I am using all four driver slots.
One of the A4988 driver does not allow the Arduino to turn on, if 32 steps jumper is selected for that specific slot.i.e when m0,m1,m2 is inserted.

but the same driver board work with 4 step setting i.e 1 or 2 jumpers only.
So I had to configure my Y axis parameter for 4 steps and rest axis for 32 steps which is awkward.
Is it a faulty board or can I do something to enable 32 steps for this particular board I have only 4 driver boards and it takes long time for shipment to reach my place for new drivers.
Regards.

By: Bertus Kruger

Bertus Kruger — Thu, 30 Jul 2015 08:51:13 +0000

Yes, you will have to swap the two pins.

By: Tobi

Tobi — Wed, 22 Jul 2015 13:05:05 +0000

Hi,
i´m wondering how to connect any kind of “spindle enable” in grbl 0.9 on the cnc shield!? Do i have to connect the sondle enable to Zx Endstop?

By: Radu Negrutiu

Radu Negrutiu — Tue, 21 Jul 2015 11:23:28 +0000

Great , thanks.

By: Bertus Kruger

Bertus Kruger — Fri, 17 Jul 2015 19:28:33 +0000

Hi. Yes, those are the only pins that swapped in V0.9i. the pins can only source a few milli amps and needs a transistor to driver higher current.Yes, on the end stops. Keep in mind that GRBL is configured for always open end stops.

By: Bertus Kruger

Bertus Kruger — Fri, 17 Jul 2015 19:23:40 +0000

Hi. Yes,Powering the Arduino from USB and the Shield from the +12v is the way to do it.

By: Bertus Kruger

Bertus Kruger — Fri, 17 Jul 2015 19:21:05 +0000

Hi Isaac, the CoolEn is an 5v output pin that goes when the Coolant G-Code command is entered. The pin it self can not be used to run a fan as the output pins on Arduino’s can’t source more than a few milli amps. This pin however can be connected to a relay to switch on a fan.

By: Isaac Dias

Isaac Dias — Wed, 15 Jul 2015 13:42:01 +0000

Hi, Bertus.
On the board, i see a CoolEn conector.
What that means?
Is it a conector for a cooling fan?

By: Hart

Hart — Tue, 14 Jul 2015 12:36:37 +0000

Hi, I am fixing to configure my first cnc with uno and cnc shield v3. I have a question regarding the changes in grbl 0.9i. Do I just connect spindle to z endstop pins and z endstop to spindle enable pins? Is the current through pins sufficient for 1.7amps spindle draw? I had planned to use a digital relay. Also, I had planned to use high and low endstops. If I just switch the pins, should I wire the endstop switches parallel to one another external to the shield? Any help would be greatly appreciated.