I am thinking of building a new gantry router. THK Slides, ball screws, aluminum construction all the goodies. My question is how to figure potential rapid traverse speeds.
I want to use some exeisting steppers that I have. Some of the Automation Direct 276 oz. in models. Planning 5 tpi ball screws and some sort of grear reduction to keep rapids up and stepper rpm down.
I am figuring in my head I want 100 IPM rapids on at least x and Y axis.
So My formula is this. 100 ipm x 5tpi screw = 500rpm the motors need to spin... Way to fast according to the torque curve of the motors.
So I figured I would add 4:1 reduction to get the motors down to 125 rpm. should work nicely. 100 IPM is nice, but would settle for slightly less say 80 or so. Using 100 so I can error slightly and still be pleased. I know I can cut at these speeds.
Question is ---- Is my thinking (calculations wrong) or am I forgetting anything? How will microstepping or the weight of the gantry affect my calculations? How can i figure how much torque will be needed based on the weight of the gantry to push these speeds? How is the torque affected by gearing like this?
Thanks All
Hack