There is a nice picture of a worm gear here: http://www.nd.edu/~manufact/FME%20pdf_files/FME_Ch15.pdf

Why not use Michaels script for a spur gear?

 
Might have to do some math to figure out the module?
http://www.roymech.co.uk/Useful_Tables/Drive/Worm_Gears.html

On the other hand, looks like you might need a helical gear script: ?



Does anyone know if it is possible to get a worm gear mechanism to work using a spur gear. I am just trying to make a small model of a worm gear out of acetal plastic for demonstration purposes only. I am thinking it might work as long as the pitch on the lead screw, is the same or a little larger than the pitch on the spur gear. What do you guys think?

Posted by: randykimball ®


Yeah, you can do it for a demo.. I'd think about having the worm at a slight angle so that the area contacting the spur teeth is actually mostly flush against the tooth. Realize that a true gear to match a worm is derived from a helical gear with the helix angle matching the pitch of the worm.


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