Need Help!- Z axis issues

[cce1911]

I have an X2 mill running with Mach3. I've calibrated the X and Y axis just fine, but I'm having all sorts of problems with Z. If I put a dial indicator on the z and calculate the steps per unit using the button on the Settings tab, I can get accurate z movement using the MDI interface. However, as soon as I zero all three axis on my part, I can't get the depth of cut to come out correct.

For example, I set the dial indicator on zero and used the Automatic Setting of steps per unit dialog. I enter a Z of -1" and then get a reading from the dial indicator. I enter this value in the next prompt and accept it's recommendation. I can manually issue Z moves and the dial indicator will read within .001 of what it should. Next, I zero out on my stock and move .5x.5 then plunge to 0.150. When I measure the depth of the plunge it is around 0.097.

It seems like when I put a load on the z axis it misses pulses or skips or something. Any ideas on what I'm doing wrong or have mis-configured?

[nova24]

Sound like something is loose. I had this same issue and it turn out that the bolts holding my router were loose. This allowed the router to raise up whenever I maid a cut. Try cutting a pocket with an end mill and see what the bottom of the pocket looks like. Mine had all kinds of ridges when my bolts were loose.

Dennis