[sansbury168]

Hi

I am almost done building my 3'x6' router and have a couple questions.

Question 1:

Formula for setting counts per inch in the trajectory planner.

Specs for X & Y:

Motor 200 steps per rev x 16 microsteps (Kstep) = 3200
Ballscrew 25mm lead
Pulley Ratio 1:1.5 (Drive Pulley 24t, Ballscrew pulley 36t)
25.4mm (1 inch) divided by 25mm lead = 1.016 revolutions per inch

Equation: 3200 x 1.5 x 1.016 = 4876.8 counts per inch

Specs for Z axis:
Motor 200 steps per rev x 16 microsteps (Kstep) = 3200
Ballscrew 5mm lead
Pulley ratio 1:1
25.4mm (1 inch) divided by 5mm lead = 5.08 revolutions per inch

Equation 3200 x 1 x 5.08 = 16256 counts per inch

Am I missing anything?

Question 2:

I have mechanical limits all set up and working properly at (36.5" and 72.5"). Do I use soft limits to define my cutting area at the 36"x72"? I realize that the preset formula is really large to keep them from activating during set-up but I am not sure of the measurement/settings/scale for setting them.

A HUGE thank-you to Tom and all the other members that have answered questions for other members as I have made it this far by reading those responses.

Clayton

[TomKerekes]

Hi Clayton,

Your math looks correct to me. A simple check is to move some large distance like 10 inches and measure if it really moves 10 inches.

Soft Limits are implemented in KFLOP and are in Units of "Steps" like everything in KFLOP. It doesn't usually make sense to enable them until after the axis has been homed and machine zero has been established. It is up to you how you want to establish machine zero but typically after homing the axis is moved some amount inside away from the limit switch and "zeroed" (assuming you home near the negative limit). So for example if your X Travel is 36 inches you might set the Negative Soft Limit to be near zero and the Positive Soft Limit to be near 36x4876.8 Steps. Note that when Jogging KFLOP will trigger a FeedHold when the soft limit position is entered so some extra distance is needed to come to a stop before hitting the hard limit. GCode should be prevented in KMotionCNC from entering the Soft Limit at all.

Please use Test Release 4.33l as there have been some bug fixes regarding jogging out of Soft Limits.

HTH
Regards

[sansbury168]

Tom

Thank-you!! It makes sense now.

I am amazed by your excellent products and support.

Clayton