1) The deepness of the engraving of the letters really depend on the pressure being exerted on the diamond tip via the lever. With all thing the same, the deepness of the engraving should be the same for the same pressure on the lever.
2) What is the size of the ring? For the self-centering jaws, users can change the groove accordingly to fit different sizes of the ring.
3) What is the maximum size of ring that your customer want to engrave?
I will check with my production to see how we can resolve this.