chuck/tailstock barriers
Its been a while since I've been programming in Camsoft, but it is a lot of fun to try to make hazy notions work out correctly in hardware operation
I finally came up with a method to set chuck barriers based on the tool number. I've always had a pet peeve about setting barriers on the lathes I've owned, since the barriers are typically too stupid to take into consideration the length of the tool.
For example, if you are OD turning right up close to the chuck, and then have to use a bar to bore inside the chuck jaws, a typical fixed Z barrier is useless because either it permits the turning tool to crash into the jaws or it prevents the boring bar from getting all the way into the bottom of the hole. This is because ordinary barrier limits are based on the carriage position, not the tool tip position.
My primary concern is the Z barrier, and fortunately, there are just enough empty parameters in the tool parameter table to accomplish this easily. I use custom1st and custom2nd for the forward and back limits in Z. Part of my tool offset measuring logic asks me to enter barrier distances for each tool as it is being set up, so I don't forget.
The X values of the barrier I simply leave the same all the time, and they are set just before the physical limit switches. Since my machine has front and rear toolposts, and machines in either CW or CCW this is about the only way to operate it.
The nice thing about the Camsoft soft limits is that the machine doesn't make the current move if it is not possible to reach the endpoint. So this can be expedient when proving a new program.
So with each tool call, I have a custom gcode written to call up the barrier values of the current tool. So my tool call looks like this:
T1 M6 G177
G177 contains logic to reset the softlimits forwards and backwards from the current tool number parameters, and turn them on. Its not rocket science to figure out once its done
First you get good, then you get fast. Then grouchiness sets in.
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)