How close of a tolerance can you get when probing in a machine?

[Jason @ CPM Industries]

Is anyone using the probing add on for mastercam?  How close of a tolerance can you get?  We currently have a couple haas machines with renishaw probes and want to add this program but worried we cant probe within .0005".  Any feedback would be great.

 

Thank you.

[Joe788]

Depends on what you mean, and the sizes you're talking about. If you're talking about just measuring a width, or a bore, step height - etc, even your Haas machines (as long as they're in good shape) will get you .0002 or better results. If you're talking about measuring a 39 inch long part on a 40x20 machine, don't count on it unless you're in an air conditioned building with coolant temperature control.

 

The location tolerance is a little trickier - since you bring the repeatability of the the tool taper, squareness of the Z axis, etc into play. But you should still be able to repeatably set your offsets within .0005 or better.

[Sticky]

I think the largest issue on a 3 axis machine is being able to probe in a manner that allows you to detect of you have a machine squareness issue. Its going to be really hard to do, so while you might get .0002" or better repeatability location is gonna be beotch.

 

*On edit I noticed Joe actually said the same thing in his last paragraph.

[FROZEN]

It works best if you have a master part in the machine to probe first then probe a current part for dimensions.  I do not have the post or seat in mastercam yet, but will be using the renishaw probing cycles on a high production job in a Makino.