Im trying to determine what size motors to use on a CNC PCB gantry type router (about 24" x 24", ground rod with lenear bearings and ACME lead screws direct drive). Problem I am having, and it mat be a really stupid question (Im a CNC newbe), but I have no idea what speeds are considered slow, fast or normal for ganty (axis) movement. Most of the calculators that suposidly figure out motor size ask what speed you want to run at (possitioning and cutting speed), but I have no idea what speed is good lol. I sure dont expect my machine to fly like some huge industrial ones, but also dont want to wait 2 weeks for a board to finish .... so

What are normal speeds when dealing with PCB isolation milling .... or better yet, whats the range (bottom slowest - highest for a small machine). At least if I have some idea of a speed range I can work out what size motors to get. Also, what is a typical (or nominal min-max) cutting force exerted when doing PCB milling. Once I get a handle on this I can at least try to figure out what size motors. Sure dont want to buy a 600 oz one when a 30 oz would do.

Thank you all