Re: Build CNC camshaft grinder
Originally Posted by
studman
Being a bit of a novice on the electronics side, I am a bit unsure of how to properly set up / program the timing vs position. I wish there was a simple way of telling a machine: "IF cam position is "---"degrees, send "X" axis to "-.--" position. Then you would simply build a lobe by programming the X position for every one of the 360 degrees or how ever many pulses you have per revolution.
Thanks in advance.
It's even simpler than that from a software perspective. Just draw the cam profile in any CAD program, and the create the tool paths in almost any CAM program, the load the resulting G-code into the CNC controller and press GO. A little bit more to it than that, but not much.
Another way would be to describe the cam profile mathematically, somewhat as you suggest above, and simply output the result as G-code. Pretty easy to do with simple programming or could even be done in an Excel spreadsheet. Just let the computer best fit the arc between the points to get best resolution and a smooth profile.
In either case, the resulting G-code will be much like that for a lathe with a C axis.
The hardware might be a bit more of a challenge, but not that difficult to do. I would start with a machine that was designed for grinding round stuff like a cylindrical grinder or maybe even a cam grinder if you can find one.
The controls and motors are readily available from many vendors. To grind accurate cams you are going to want good resolution accuracy, and repeatability, so good hardware is going to be required.
Jim Dawson
Sandy, Oregon, USA