GRBLDuino Shield CNC Controller

Over the past few days I’ve been designing a Arduino Uno CNC controller shield.

My requirements were pretty simple:

• GRBL 1.1 compatible
• Pin compatible with Pololu DRV8825 drivers
• User replaceable stepper motor drivers
• Screw terminals for connections
• E-Stop, Abort, Hold, and Resume buttons
• Probe connection
• Spindle PWM control
• User selectable 4th axis function (clone or separate)
• No SMD packages in the first version

Arduino CNC shields are pretty easy to find (and shockingly cheap) but not many are compatible with the changes in GRBL 1.1. I didn’t want a product that was out of date before I even purchased it.

My design is loosely based on the Protoneer Arduino CNC Shield. I fully support the purchase of the Protoneer product but it is hard to get in the US – available only from his eBay store.

I’m calling the controller the GRBLDuino Shield as I have plans (partially completed, too!) to design an integrated version with the Arduino built in after this is complete. I want an easy to set up, easy to use, and inexpensive product not (overly) intimidating to new users.

 

I don’t want to release this as OSHW just yet but the schematic above along with the Gerber files should allow anyone motivated enough to duplicate GRBLDuino pretty easily plus it lets you see just how much goes into one of these shields (more than I expected going in).

Bill of Materials:

• 1x GRBLDuino Uno Shield PCB
• 15x Two position screw terminal blocks
• 8x 1×8 female pin headers
• 1x 1×3 male pin headers
• 4x 1×4 male pin headers
• 1x 1×6 male pin headers
• 2x 1×8 male pin headers
• 1x 1×10 male pin headers
• 2x 2×4 male pin headers
• 4x 2×3 male pin headers
• 1x tactile switch
• 1x 10k ohm resistor
• 1x 680 ohm resistor network
• 4x 150nF ceramic capacitors
• 4x 100uF 50v electrolytic capacitors (genuine Nichicon)
• 12x short 2 pin jumper shunts
• 3x long 2 pin jumper shunts
• 12x short 2 pin jumper shunts
• 3x long 2 pin jumper shunts

The board layout is complete and the Gerber files have been sent off to EasyEDA/JLCPCB to produce a small batch of prototypes for testing.

Boards and components have arrived, been assembled, and tested. These are now for sale through a few outlets. The best price will be at the Eccentric Workshop store, but they are on Tindie and eBay.