I have been trying to draw a gear (for a gearbox) and have to come to the conclusion that these drawings are done by witchcraft (or aliens)!!

Having read bits and pieces, am I right in thinking that the gear is "drawn" by an autocad macro (lisp program)??

I have searched for this but am unable to find a macro on the web.

Am I meant to figure out how to program in LISP to create this gear?

Cheers

Colin