Design a Parametric Pulley (DXF / STL)

When I needed to make a pulley for a sumo robot I was building. I didn’t quite find the all in one solution I was searching for, I just needed the DXF of a specific tooth profile for a specific number of teeth.

So I could import this in Fusion 360 to make the custom pulley I want.
I found out about a parametric pulley designer on thingiverse http://www.thingiverse.com/thing:16627 but I couldn’t edit them in Fusion 360 to my needs.
I found a workaround on a site: http://rasterweb.net/raster/2012/07/16/openscad-t... .to export the tooth profile as a dxf.

And I simplified the complete workflow into one scad file. So you could easily generate a custom pulley with a specific: number of teeth, tooth profile and shaft diameter.

Opening the File

You can get the latest version of the scad file on my thingiverse http://www.thingiverse.com/thing:2316122/#files

Or you can get the file in this step.

To open the scad file you need to download openscad. Which you can find here for free: http://www.openscad.org/downloads.html

Downloads

Pulley_T-MXL-XL-HTD-GT2_N-tooth_dxf_generator_custom - Copy.scad

Editting the File

Edit the parameters you see in the first three lines.

N_tooth = 42; //number of teeth
shaft_Dia = 4.2; //shaft diameter in mm
profile = 14; //profile options: 1=MXL 2=40DP 3=XL 4=H 5=T2.5 6=T5 7=T10 8=AT5 9=HTD_3mm 10=HTD_5mm 11=HTD_8mm 12=GT2_2mm 13=GT2_3mm 14=GT2_5mm

When you changed the parameters press F6 to render the design.
If you are satisfied with the outcome you can export the file as a DXF.

This DXF can be imported in almost every vector program and cad program: Fusion 360, Autocad, SolidWorks, Inkscape...

In the next step you'll see how I make an example pulley in Fusion 360. But you can stop here if you just need the DXF.