I am new to CNC and I am planning a CNC Router. As I like to tinker I want to do most of it myself. So far I have stepper motors, a controller and my own software which drives the stepper nicely via the controller. I intend using off the shelf software to generate G code files from a DXF file. Now, the G code defines only the geometry of the toolpath. A workable toolpath must also have a description of the kinematics (motor speeds and accelerations). There is stacks of info out there on most aspects of CNC, but this critical, and non-trivial aspect of kinematics is nowhere to be found. Is there a conspiracy amongst kinematics gurus or can someone help me?
Many Thanks
CNCMP
Hi Guys
Thanks for all the useful comments. I especially liked Hufungdung’s “First you get good, then you get fast”, actually I will happily settle for good I don’t much care about fast! I think my concerns stem from a lack of experience with CNC cutting.
Working out a sequence of speeds and accelerations is easy enough for a single segment where the tool is at zero velocity at the start and end of the segment. But when you have two or more sequential segments and you want to keep the tool moving the problem becomes tricky. Is it OK just to plan each move of a large sequence with the tool at zero velocity at the end of each move? I have visions of a CNC router constantly stopping and burning the workpiece. Is it the case that in practice as the electronics works at high speed and the “stopped” periods are momentary the system runs smooth and continuous despite all the theoretical stops?
MP