Delta effector system for 20x40 Vslot w/spring-ball joints

thingiverse

I was looking for a carriage design that didn't use magnets and would be easy to disassemble, but couldn't find anything that met my requirements, so I made this myself. The carriages use the openbuilds mini-v wheel kits and are designed to ride on the wide face of 20x40 v-slot extrusion. The spring clipping arrangement was based on some photos I've seen of pick&place delta robots. To assemble everything, print the following: three carriages (either V1 or V2), one effector, twelve rodends. When tightening the tapped ball bearings, wrap a cloth around the ball before gripping to prevent scratching the surface. To fit the rod ends onto the rods, construct a jig to ensure they all have the same effective length. I drilled some holes in a plank and mounted two ball bearings there temporarily to hold the rod ends at a fixed distance when epoxying them in place. The fit of the mini-v wheels onto a 20x40 extrusion that I encountered was quite snug, but if yours comes out loose, use a bent paperclip or some printed tensioner to hold the free ends of the mini-v wheel shafts together. V1 is shown in the photos, but upon assembly I realized that the springs would rub against the belts. V2 has the belt mounted closer to the carriage plate and ball bearing mounts are up out of the way. Longer bolts can be substituted for the M5x25mm ball bearing mounts, but the gap between mounting points should be increased to allow the longer bolts room to slide in. A full BOM includes the following: * Twelve M5x25mm machine screws (to mount ball bearings) * Twelve 10mm slotted, tapped ball bearings (found on eBay, I was told that these are normally used for some photography purpose) * Six arms of your choice, six millimeters OD (shown: pull-truded carbon fiber from Goodwinds) * Six M3x10mm machine screws (for belt mounting) * Nine openbuilds mini-v wheel kits (http://openbuildspartstore.com/delrin-mini-v-wheel-kit/) * Twelve eye hooks (~1.5 millimeter shaft, found at hardware store, open or closed loop will work) * Six two-inch to two-and-a-half-inch extension springs (found at hardware store, or McMaster if all else fails) Print Settings Printer Brand: Printer: prusa mendel i2 Rafts: No Supports: No Resolution: .2 millimeter Infill: 40% Post-Printing Cleanup I encountered a great deal of difficulty getting clean holes from my old reprap, and I would suggest thoroughly drilling out the slots and holes before attempting assembly. The rod end cups should be cleaned up with a ten-millimeter ball endmill.