PM25MV Quill DRO

[FFlores63]

This is my first mill and I'm just starting to learn the functions of the machine. My machine only came with the factory installed Z axis quill DRO. I have been practicing by trying to square up a block of aluminum and when I try to to remove a set amount of material using the DRO as a guide I get inconsistent results. I have been using the following steps: First I crank down the head to where the cutting tool is just above the material, then I lock the head. Then I use the quill handle to bring the tool to where it is just touching the material, then I lock the spindle and zero out the DRO then I move the material over using the x axis to bring the material out from under the tool I then unlock the spindle and I use the fine adjustment knob to bring the tool down, let's say 10 thou using the DRO. I then make a pass but when I check to see if I only took off the amount I had set on the DRO I find that it took off more material than I wanted. I forgot to mention thst I do lock the Y axis also. What am I doing wrong. Thanks.