Quote Originally Posted by John S View Post
Yes moving gantry design
Well couple years ago built a belt machine for a friend in Ireland have a look here. New Machine Build Belt Driven extrusion framed wee beasty!! - CNCzone.com-The Largest Machinist Community on the net!

Built from scavenged bits with a few new. Check vids in post #5 and you'll see it wizzing about.!!
In the Vid with moving gantry it was running 3:1 ratio and that wasn't enough so ended up at 6:1. @ 3:1 the motors weren't happy at low speeds.
I was restricted with room to use larger pulleys and just happened to have a spare belt and pulleys so thats why it ended up using the setup it did. . . Not ideal but got the job done.!!

The point telling this was to make you aware of the ratio your likely to need for smooth machine at low feeds.