Actually guys, the taper column does come in handy many times.
The problem with programming the taper out is that in some cases the taper is incosistant.
IOW as the insert wears, so will the taper amount change. You replace insert, taper will change.
Having to modify the program each time is a lot more involved than simply changing the taper offset just as any other offsets.
No, it isn't an end-all solution for everything, but for the right application, it's the cat's meow.
Now how it works is much simpler than to figure out what EXACTLY do you need to put in the field.
Basically, think of the "taper" value as you'd think of the I value in the G76 threading cycle.
In the threading cycle, the target X value is at the end of the thread, while the I defines the radial distance from the target X to the front of the thread.
So, as a result, for a tapered OD thread you program the X at the end of the thread, and since the front is smaller the I value will be negative.
Now to the taper offset, it works on pretty much the same principle, except it goes by 1" increments.
What that means is that the control considers the taper value as a diameter change for each 1" of Z travel.
So, as a result, if the diameter is smaller on the front of the part and larger on the back, then the taper value is negative.
Example.
You're turning a 1" diameter for 1" long. After the finish pass you measure 1.000 on the back of the part and .999 on the front, you would enter -.001 in the taper column.
Now if you're turning a 1" diameter for 2" long and measure 1.000 on the back and .999 on the front, you'd enter -.0005 for the taper because the difference is only .0005/inch.
Again, this isn't a solution for all taper issues because the closer you get to the chuck typically the less deflection you have so the difference isn't linear, but I have
successfully used it on many instances.
