The RepRap "Cubit" New Printer

thingiverse

Please wait before printing one of these; it's still a work in progress - pictures will be available soon. All the holes seem to line up so it looks okay to print now, and it appears sturdy enough to handle quick movements. (Using a remote extruder will keep it light.) It has only 8 1/2 inches of build height, so if you want more, cut your thread rod longer than 18" - I would suggest cutting it to 20" or 26+" if you want to print larger T-slot. The z carriage is very tight, so you don't need screws to secure them; just hammer them in. Print four of each block with V10 settings. It takes about 4 hours to print each block, and you can do it without supports. Prices are in CAD: * 72 - 1/4 inch nuts: $10 * 15 - 5/16 inch nuts: $3 * 2 six-foot pieces of 1/4" thread rod: $16 (IIRC) * 3 three-foot pieces of 8mm smooth rod: $18 * 2 three-foot pieces of 5/16 thread rod: $12 * One 1 1/2 inch long 5/16 bolt with a smooth part: unknown price * 2 one-kilogram rolls of PLA: $40 * Ball chain: $10 * 6 z608 bearings: $10 * 11 LM8UU bearings for the slides: $10 * Parts cost about $90, and $130 with PLA. Electronics: * Ramps 1.4: $6 * LCD: $10 * Arduino Mega: $6 * Steppers (3): $33 each, so $99 total * 5 stepsticks (the red ones): $10 * Heatbed and glass: $20 * PSU: $20 * Total cost is $105. Printing at 50 watts for 20 hours still costs less than $5, so I won't factor that in. The total cost is $230 unless you want to print a larger 3' version; then it will be about $260. The top z608 bearings need a bit of cleanup on the tops where the print sagged. Use a Dremel with a carbide tip or a drum sander attachment. Print the 516 dual ballchain gears and one single for the x-axis, even if you're only using one piece of ball chain. Double nut the sides where the nut insert is to prevent loosening. Also print two NEMA 17 dual ballchain gears. I was thinking of using shrink sleeve and a piece of wire around it to secure the Y-axis dual ballchain or maybe just a short piece of SS wire. Where the non-motor side bearing is, you'll have to grind down the bolt head for clearance on the x-axis. It's really close to the smooth rod and has to spin still. You might need to make a drill hole into where it touches the block or cut the bolt end off and shave a nut down. You could even go for a full 3' or weld two together to make a 6' version if you attach it to something. Cut the heatbed base board to 11.5" (could be 12") x 9" with 1/4 inch thickness, and fasten it with 1/8" x 3/4 bolts from Home Hardware's clear package with a white label and blue writing. I'm going to use a Cyclops hotend converted into Chimera for dual extrusion, plus it fits well inside the cube blocks. I decided to go with 4.4mm ball chain. The blocks print standing up without supports on my printer. My next version of Cubit will be using 2020 or 3030 printed T-slot 3D, hopefully more efficiently using plastic and time. If all goes well with the strength tests, gluing thread rod in place as joiners also do a melt-in-the-middle with two pieces. I borrowed a few parts from https://www.thingiverse.com/thing:2260317