Usage1. Draw the first arbitrary gear.
2. Open Extensions -> Render -> Unordinary gears
3. Fill in teeth number for first and second gear. (This numbers are relative to each other, so instead of 14:28 you can enter 1:2.)
4. Enter number of copies. The bigger this number the smoother will be the gear. For the preview 50 copies will be enough, for the final render it could be about 360.
5. Enter the distance between the centers of the gears.
Press applySo you should get something like this: Then enter into created group (double click on it), select all paths Ctrl+A and make boolean add Ctrl+Shift+"+": Now break path apart Ctrl+Shift+K and delete everything except the inner path: Your extraordinary gear is ready !
You can make it a little smoother, go to node editing mode F2 select all nodes Ctrl+A and make all segments straight (a button at the node editing menu).