/diy/ - Do It Yourself

>>1859404
A worm gear drives a helical or straight-cut gear for speed reduction. It also prevents the output from free-spinning or applying reverse-load against the drive source. So when the drive motor isn't spinning, the driven side can't rotate at all.
The thread profile for a worm gear is usually pretty different when compared to a leadscrew. Worm gears have a wide diameter difference between their major and minor in order to allow the gear teeth to engage them fully and will obviously have to match the pitch of the output gear.