okonk / roadkill

_{A MakerBogans & Safflower Production}

Roadkill Enhanced Toolhead PCB Family

The RKE family of toolhead boards are based off the roadkill board designed xbst_ but offers numerous improvements.

• Heater current capacity is greatly improved offering 5A of capacity on the RKE-Long board and 6A on RKE².
• Support for simultaneous use of neopixels, filament sensor, inductive probe and x endstop switch with dedicated ports for all features.
• All boards within the RKE family are pin compatible allowing for mix and matching of boards.

Important Notes

• Heater screw terminal is polarised, as the 24V supply is used as a common rail.
• Nylon or printed washers should be used to protect the mounting holes due to the proximity of the traces to the holes.
• LED port is designed for neopixels and uses a common 5V rail with the filament sensor port.
• Probe port has a 24V power rail derived from the heater.

⚠Do not connect a wire between the MCU and the Roadkill probe port for V, this will result in backfeeding 24V into the MCU. V is provided from the Heater

BOM

Per Board,

• 1 x 20 pin IDC header (2x10 2.54mm pitch)
• 5 x 2 pin JST-XH
• 3 x 3 pin JST-XH (2x for RKE Long)
• 1 x 4 pin JST-XH (2X for RKE Long)
• 1 x 5 mm pitch screw terminal (TB00250002BE)

Molex temp-flex ribbon is the preferred ribbon solution (Molex, 100057-0101).

For IDC connector/sockets 3M D89120-0131HK with D3448-89120 strain relief clip are the preferred solutions.

Pinout for Ports

IDC numbering is ODD_EVEN with 1 denoted by an arrow on the PCB

Pin 1 of the JST-XH ports is the square pads on the PCB.

For RKE²

Port	Pin 1 (IDC PIN)	Pin 2 (IDC PIN)	Pin 3 (IDC PIN)	Pin 4 (IDC PIN)
Layer Fan	Fan Voltage (18)	Fan GND (20)	-	-
Heater Fan	Fan Voltage (14)	Fan GND (16)	-	-
X endstop	GND (2)	Signal (12)	-	-
Filament Sensor	5 V (4)	GND (2)	Signal (10)	-
Neopixel	5 V (4)	GND (2)	Data In (6)	-
Probe	24 (1,2)	GND (2)	Signal (8)	-
Thermistor (T0)	T0 (11)	GNDA (9)	-	-
Extruder Stepper	A1 (19)	A2 (17)	B1 (15)	B2 (13)
Heater	24 V (1,3)	HE GND (5,7)	-	-

RKE Long utilises a combined Filament Sensor and X endstop port pinout is below.

Port	Pin 1 (IDC PIN)	Pin 2 (IDC PIN)	Pin 3 (IDC PIN)	Pin 4 (IDC PIN)
Combined FS and XES	5 V (4)	GND (2)	Signal (12)	Signal (10)

Schematic

Probe Wiring

It is critical to wire Z probe correctly to avoid damage to MCU. Follow the below wiring guides

Troubleshooting

Number	Symptoms	Cause	Solution
1	X endstop is permently triggered or not triggering	X end stop is shorted to GND on the MCU->Roadkill board, S is connected to G on the X endstop port	Swap X endstop pins on the MCU->Roadkill board
2	Probe disconnecting when heater is turned on, Flickering Probe during PWM control of the Probe	Reversed Polarity on the 24 V Screw terminal on the MCU->Roadkill board	Swap Heater Wires on the MCU->Roadkill board

License

This work is licensed under a Creative Commons Attribution 4.0 International License.