Mechanical paint mixer

grabcad

For MFET 3460 final project.This model was made to fill the gap in hobby paint mixers. Paint mixers available are motor based, and I think a mechanical design is visually more interesting. This paint mixer was designed with hobby painters in mind, with the paint pot sized specifically for citadel paint pots, though a wide range of model paints will fit inside. The model is designed for home printing, with larger parts being made of assemblies of printer bed friendly sizes. Additionally, overhangs were avoided as much as possible to reduce support material and decrease chances for prints to fail.The only external part are the 6 plastic ball bearings from McMaster-Carr (https://www.mcmaster.com/6455K2/) for $7.54 each. These open, lubricant free bearings help with smooth motion. 3d printing your bearings would reduce the cost considerably, but that is beyond the scope of the project.The print has a volume of ~55 cubic inches, or ~903 cubic centimeters. Since ABS filament has a density of 1.04 g/cm^3, and assuming a 20% infill, this will mean using around 188 g of filament. Spools of filament are usually sold at around $20 per kilogram. This means the full print will cost under $4 of material. With the bearings, the cost is under $50. To hold the paint inside the pot, a printed spring is used. This compliant mechanism holds the paint pot against the lid during mixing. The most difficult part of creating this was the gears, as the solidworks gear toolbox is not as flexible as I needed. I spent a lot of time trying to draw custom gears and made a template for hand drawn spur gear. But when I found out how to convert toolbox items, it was a simple matter of creating the gear profiles using the toolbox, then editing the other features of the gear. Two gears were generated and joined to make a transition from the handle bevel gear to the spur gear that drives the first ring.The simulation result is assuming the gears seize and a person is pushing with full strength. The yield strength of abs is 5.8 Ksi. As the simulation shows the pin to the gear would twist off very quickly.Picture in render from https://www.pinterest.com/pin/464715255292957033/