Rich and Hood,
I really feel bad because I am making you waste time. I have read the manual, all three of them, extensively, repeatedly over the last month or so. I have avoided getting on the forum until I felt I was asking questions that I could not find the answers to in the manuals. (I am not saying the answers were not there, but that I either could not find them or could not understand them).
Almost everything you wrote in the last three posts I understand pretty well. In addition to your manuals I have read Briney on Machining, both Hayden and Hess on CNC Machining and Programming and I am a good way through Smid's Handbook on CNC Programming. I think I just am not good at expressing my question precisely.
I was referring to homing without homing switches. Your manual says, I believe, that you can enter data in all DRO's and hit Enter. So when I was trying to set up machine zero, I thought I should be able to do it relative to where the tool tip currently sits. So I tried and the system appeared to refuse to accept a value (which appeared to contradict what your manual says). So that is the reason for the question.
I think I understand offsets. I understand radius vs diameter. But what if you don't want to use an offset? What if you are running a simple program and you simply want machine zero to be program zero. I understand that that is not recommended practice, but I see no logical reason why you should not be able to do it.
I my specific issue I have little delrin rod that I am trying to turn and then cutoff. I want to do this repeatedly. Program zero is -.1" from the stock face so that I can face the piece before turning and cutting. I wanted to make machine zero - program zero and I wanted to do it without having to jog around the stock to y=0, I just wanted to leave it at x=0 and tell it where y=0 was (-.1 from the stock face). This would make my repeated operation a lot faster.
So, I guess, from reading what you wrote the answer to the question is that no, you cannot set Home be defiining a location. You have to be at the location you are setting and the only value Mach3 will accept is zero.
If I haven't completely exhausted your patience I would still like to understand two other things: 1) what is a work coord. (from the Manual Screen)? Is the same as a program coord.? 2) when you are in the two Auto screens how can you tell if the Axis DRO is showing you macihine coords. or offset coords.?
Thanks. Frank