For about a year and a half I'm running the beginners setup with a Acme 1/2-10 single start screws and I'm getting tired of the lack of precision and the overall play within the machine movement. I's a fine setup for the money invested but I'm stepping up. I'm fixing to get rid of all the MDF except the table that is solid and bolted to a steel structure and go with real linear bearings. I followed the previous post talking about the issues with 2 & 5 start screws trying to find out what would be good precision screws without going bankrupt so I wanted to create a separate post just dealing with precision instead of speed.
My second issue would be the movement of the machine when it's cutting a curve or a circular pattern. This does not happen with small radius patterns but on the larger ones the machine does not follow the curve cut in a smooth motion and it travels in waves as it receives the information from Mach3. It does not have the constant velocity on curved patterns (diagonal straight cuts are fine) and I know there is a setting for CV in Mach3 but if I set it on then my sharp corners come up rounded.