Ultra MegaMax Dominator (UMMD) CoreXY 3D Printer

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This is my fourth and latest 3D printer design targeting high quality, reliability, and moderate print speeds. It stands about 1.5 meters tall and weighs around 35 kilograms. This printer fits perfectly into my Prius when laid on its back with the hatch closed, allowing me to transport it across town without any adjustments required. I can take it out, stand it up, and start printing right away without needing any leveling or adjustments. The bed plate is a sturdy 300 x 300 x 8 mm piece of MIC6 cast aluminum tooling plate with a 0.7 mm layer of PEI on top and a powerful 750 W line-powered heater at the bottom. It's supported by a unique kinematic, 3-point leveling system that allows for thermal expansion without putting any lateral force on the leveling screws. There's also an 184C thermal cutoff mounted on the bed plate to protect against thermal runaway in case of a controller or SSR failure. The bed is lifted by two linear guides in the 700 mm tall Z-axis using belts and an OnDrives Rino 30:1 worm gear reducer driven by a 164 oz-in NEMA-23 motor. The worm gear mechanism prevents bed-crash when power is cut, ensuring smooth operation. Belts are 10 mm wide, steel core HTD-3M type, with measured belt stretch under load at 42 um/kg - an utterly insignificant amount. The CoreXY mechanism employs two level, 9 mm wide, glass core, Gates LL2MR09 GT2 belts for smooth motion. Twenty-four 8 mm linear guides are used in both the X and Y axes, while A and B motors are 64 oz-in, 400 step/rev, NEMA-17 size. The X-axis design allows for thermal expansion of the printer's frame without creating huge side loading on the Y-axis bearing blocks and rails. This printer features a single Titan extruder with a v6 hot-end for efficient printing. The controller is a Smoothieboard that drives all motors directly, including the NEMA-23 motor powering the Z-axis. Printing is done from SD cards plugged into the LCD interface for maximum reliability. The frame is made of sturdy 40x40 mm aluminum t-slot extrusions with corner braces added to increase fore-aft rigidity. There's about 18 W of white LED and 20 W of UV LED illumination built in, making it perfect for printing ABS. The machine is fully enclosed, with all electronics and A and B motors located outside the enclosure. The side back and bottom walls are made of 8 mm thick dual-layer polycarbonate that fits into the slots in the frame, providing obstructed light transmission and thermal insulation - and making modifications a bit more challenging. Front panels are made of clear polycarbonate sheet, with the upper front panel fitting into the slots in the frame and the lower front panel attached using magnetic strips. I deliberately worked to minimize the number of 3D printed parts in this machine and will replace them with metal when I get around to it. Full details of the design concepts are being posted to my blog at https://drmrehorst.blogspot.com/.