Posted by Josh Ward on April 05, 2001 at 17:44:02:
In Reply to: Re: Can you cut worm gears wiithout a hob? posted by Kevin on March 13, 2001 at 08:24:26:
With a little trouble a passable worm gear can be cut on a horizontal mill using a dividing head that has the capacity of being driven by the table screw. Instead of driving it with the table screw you would drive it with a home made 4 gear combination which is driven by the spindle possibly at the back of the machine.A shaft with the ability to telescope and have universal joints for alignment with the dividing head would be needed. The cutter is a fly hob and at first it only nicks the blank .The fly is at full depth and will be advanced tangentialy in increments which involve advancing the Y axis of the machine the indexing crank of the div head and some up and down of the Z axis . I'll leave the computations to whoever wants to try this . The beers will be on me .