The trickiest stretch of this conversion has to be the toolhead wiring. The SB2240 carries a set of 1.25mm connectors, and the kit arrives with loose terminal pins and DuPont housings to sort out, alongside a pre-crimped four-conductor CAN bus cable. The maker took it in careful steps, starting with a swipe of isopropyl alcohol across the stepper driver chip before its blue aluminum heatsink went on.
Overall this is a retrofit of a Voron 2.4 core-xy printer to CAN bus, running Klipper, with BigTreeTech's U2C interface tied to a Raspberry Pi 4. The SB0000 PCB seats into the recessed inner face of the Stealthburner front cowl and is held by two screws into existing mounting holes, with the fan leads and RGB LED harness routed to matching pin headers. A printed adapter plate bolts to the rear of the SB2240, which then fastens onto heat-set threaded inserts in the toolhead frame. An Allen driver handles the umbilical strain-relief mount.
Several setup details deserve a nod: jumper blocks placed across the voltage selector pin headers, and the 120-ohm CAN bus terminating jumper set on the board. The U2C lives on a vertical DIN rail in the lower electronics bay, with red and black power wires screwed into its green terminal blocks. The U2C converts USB from the Pi into CAN signals, and using it helps avoid USB communication bandwidth constraints, which seems like a tidy gain for a toolhead board that talks constantly.
One open item remains: the maker has not yet tried an SB2209 with the U2C adapter. Everything else appears to be running smoothly, with the SB2240 working very well. Getting all those tiny jumper and crimp tasks done cleanly is what makes this conversion worth studying closely.
Project by Kapman's Basement Workshop. Watch it on their YouTube channel: