Today is my day for asking silly questions. I was re-writing my spindle warm-up routine and this thought occured to me…I had assumed that because there is a holding current to the (original open loop) stepper motors that generates at least some heat they don’t need to be exercised while my spindle routine is running. Is that a safe assumption, or should I be moving the steppers around to warm up while warming up the spindle?
Interesting! I could see that from a technical standpoint. I wonder about the approach from a safety perspective. Are you using an enclosure? Would you exercise the Z stepper as well?
There are some built-in “stepper warm-up” moves just from jogging the machine around, homing it, loading stock, and probing. I can’t say I’ve ever heard of someone warming up the motors that move the gantry, but it could be a thing.
Spindle warm-ups are certainly an industry standard for industrial machines. Curious - what did you modify in your spindle warm-up program? And what spindle are you running?
I have written a spindle warm-up routine as well, and also one that moves my axes their full range at increasing velocities. I am doing both of these more to get the bearings and rails lubricated and the oil evenly distributed, but I imagine it warms the steppers as well. From my research this is more important with expensive, highly accurate CNCs where they want to avoid temperature becoming a factor and impacting parts milled to micron tolerances.
2 Likes
In my experience in industry the concern is mainly centered on mechanical functions, i.e. run functions to ambient temperatures to eliminate dimensional drift. The majority of work from a hobby CNC does not require precise dimensional control so I believe axis warm up would actually provide little benefit.
On the other hand, I move each axis vigorously before each session too.
1 Like