Reciprocating Geneva

thingiverse

This model illustrates the conversion of continuous rotary motion into reciprocating indexing motion. It is a relatively complex model consisting of 22 distinct parts, requiring numerous M3 x 10mm long button head cap screws - approximately 34 were used in this case, although fewer or more could be employed with equal effectiveness. The model was inspired by a simulation example found within SimLab Composer Mechanical v6.18. It was designed using Moi (Moment of Inspiration) and subsequently simulated in SimLab Composer Mechanical before being printed on an Ultimaker original (modified) utilizing Diamond Age PLA. A video documenting the completed model can be viewed here: https://youtu.be/rsHtbFcT21w Additionally, a simulation of the concept is available here: https://youtu.be/dwXFKS28kUQ Print Settings: Printer Brand: Ultimaker Printer: Ultimaker Original Rafts: No Supports: Yes Resolution: 0.2mm Infill: Generally 30% Notes: Material - PLA Wall section: 1.2mm Temp: 210C Post-Printing: Typically, when designing a shaft and hole, I assign both the same nominal size, such as 8mm. In reality, I make the hole (if it is a clearance hole) slightly larger, otherwise simulation will not function properly. To achieve a smooth sliding fit, I size the hole using a hand reamer. If the hole is not reamed out, the shaft is a tap fit into the hole. It's essential to note that the handle stem is a tap fit into the handle lever; therefore, do NOT ream out the hole in the handle lever. As I currently do not possess a 14mm reamer, I added the 'geneva base no reamer' file, which features a larger bore. For those using hand reamers, these handles may be of interest: http://www.thingiverse.com/thing:386855 Additionally, I clean out the entry of holes that will be self-tapped by the 3mm screws using a tapered reamer. I own one of these: http://www.ebay.com.au/itm/Tapered-Reamer-Driver-tool-0-to-14mm-Expanding-Hole-Opener-RC-Helicopter-DIY-/121804439198?hash=item1c5c1c3e9e:g:t98AAOSwAYtWLdXy Spending some time ensuring that sliding parts move smoothly is crucial, especially for the rack in its supports. I found it necessary to clean the print table side of the rack teeth and the gear teeth. It's recommended to assemble the model with the rack central and the gear and geneva arranged as shown in the first photo. Notably, the last part to be fastened in place should be the 'block arm and roller.' Just a reminder - take care when assembling the geneva to its base, as the holes are not evenly arranged.