The machine is a LB-15 lathe with OSP-5020L control with user task 2. Currently, the offset values are in the header lines of the program and the operators type them in before running the first part. Too many times they either type a wrong number, add a - sign or just fat finger the keys and crash the machine. I'm going to keep the offset values as close to 0 as possible and I am going to change the zero set for each tool with VZOFX and VZOFZ after it is called up. Since the edit lock is always on, they can't change the values. What I want to do is limit the value in the tool offsets so the operator can't put in too large or small of a value, say + / - 1mm just to account for tool wear. I want to make this as idiot proof as possible.