I just added a vacuum table and meant to start setting my zero on the Z axis at the table top instead of the material top. My question is what will happen is I set zero to the table top, and my material is unknown, say 1.45, but I set the tool path to cut 1.5 will it cut into the table or will the machine go up to 1.5 and then cutdown 1.5 to the table top this cuttiing completely through the material
If you set your Z zero to the table top (spoil board) it should never cut into the table top unless 1) you tell it to by accident or on purpose (Vectric CAD/CAM products warn you), 2) your top is not flattened and parallel to the gantry, or 3) you did not measure the thickness of your probe accurately. The measurement is from the table top so if you say the thickness is 1.5, it will raise that high, plus your safe Z height (I use 2mm) and assume that 1.5 is the thickness. It will base its cuts on that 1.5 thickness you told it. If it is 1.45, you will just be cutting some air on the first pass. That is why it doesn't cut into the spoil board. Whereas if you zero on the workpiece and tell the machine it is 1.5 thick, but it is really 1.45, it will cut through the material and into the spoil board 0.05. I always zero to the spoil board unless I am doing a Vcarve, or Vcarve inlay. I flip my OpenBuilds probe upside down and use the 9mm thickness as the probe thickness on the spoil board. I still use it the proper way to find X and Y zero. I prefer this method because I always cut through the material, but do not destroy my spoil board for no reason. It gets plenty of abuse from screws and pin holes for 2 sided carves.
