so, i was poking around at some calculations for servos and steppers for a conversion of a bf20 or bf16. trying to see if my little parker servos had the guts for moving a bigger machine around.

the parker servos are rated for .7nm stall. in contrast my tiny steppers on the KX1 are 1.35nm stall. the servos of course have .7nm torque at 7500rpm. the steppers, not so much.

so doing my math, i arrived at a calculation for the bf16 x axis. it told me with 4mm pitch screws like i have in the kx1, i need under a tenth of a NM to move the empty table at 1G! i spent some time telling myself the math was wrong but i couldnt find out where.

so i go to the kx1, fire it up and play with the x axis tuning.
right now, partly because of some way/gib issues, its at 100ipm, and .1G acceleration. above that it has a tendency to stall at spots. part of that is certainly because the stepper torque drops to nothing due to a temporary 19v psu.

.1g is pretty fast actually. im used to watching machines on youtube winding up for ages to get to top speed. even the little ones.

so, i drop the top speed to 40ipm, and slowly up the acceleration. where did it stop? 4g's, and the motor has at least 2 times more power left in it, but i think it just cant go faster. i loaded the table and that didnt even stall it. for reference, 4g acceleration takes you from 0-40ipm in 0.00014". its completely silly, but proves you dont need a servo the size of a car to get good dynamics.

so.. the moral of the story? i dont know yet. haha. i do know that my servos will haul a** on the bf16 and bf20 though without a gear down and still have a top speed near 300ipm on 48v! yippie.