Gear Thing

thingiverse

An exercise in generating a gear profile from a photo. Definitely needs some refining, but it was getting late... General workflow- Import the canvas, then rotate to align with drawing axis. (This wasn't done and I regretted it) Scale (calibrate) canvas to a dimension on the part and move to an appropriate origin point. Use a couple of three point arcs to find the centre of the gear shape. Using that centre, measure the angle between six teeth and then calculate the number of teeth in 360º. Measure an approximate pitch circle diameter. (roughly 1/2 of the gear height outward from the root of the tooth) Divide number of teeth by the pitch circle diameter and round off to get the "Diametral Pitch" Open Utilities->Add-ins->Spur gear and press run. Fill in the boxes and generate the gear. It will show up as another component. Align the gear on top of the canvas and check for a match. You might have to generate several till you get the numbers right. Cut away the bits you don't need and draw in the flanges. Bob's your uncle!