Does anyone know how to precisely zero the x and y azis? I have a dial gauge for the z axis which works fine and is accurate but I need 3dp accuracy on x and y too so visual alignment is too hit and miss. I don't want to use an edge finder as my zeros are in the centre of my material which in turn is in the centre of my vacuum table. Z zero is either top face of my material or half way through it. Any tips, tricks or devices I should know?