Controlling unconventional 3D printers

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I have been working on a couple of research projects lately involving the creation of a concrete 3D printer and a large-format plastic 3D printer using a pellet extruder. Both printers have in common that their electronics are built around Duet 3 controller boards, as they give you great flexibility. 

That flexibility comes at a cost, as I must learn to configure the required features. Most of the time, I can find the info I need in their manuals or user forums. Occasionally, I ask a question there, too, and I always have a useful and quick answer. 

My latest challenge was to get working a four heated sections hotend. I was using a Duet 3 6HC board on that machine that features four thermistor inputs, but given that a heated bed was already using one, I was missing one thermistor input. Eventually, I had to buy a 1HCL extension board that added one motor controller and two additional thermistor inputs to the base system it connects to with a CAN bus. 

I thought I could use an old telephone RJ-11 wire to connect both boards, but when the diagnose failed to see the new board over the CAN bus, I realized I had the connecting wires inverted. Once that was fixed, it connected and worked flawlessly. And that is the beauty of these boards; most of the time, I am the one to blame if something is wrong. 

While the boards are not cheap, they come with all the additional headers and terminals to complete your wiring (provided you have the required crimping tools). And they have been delivering a solid performance in the systems I have equipped them with.  Kudos to them. 

 

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