Category: Milling Machines
I noted your comments on Z axis machining and thought I might stick my neck out here.
Your machine looks like it came with the old Philips controller from one of the early photos. They set the axes up differently to what I believe is the current convention. That is with the Y and Z axes swapped. So you might find your servo closing relays in the wrong physical order on the DIN C rail. The convention seems to be X side to side, Y forward and aft, and Z up and down. Certainly Heidenhain uses that on controllers from my TNC 155 up to 400 series. Early Bridgeports used the TNC 155 so they are that convention also.
Rotary axis A, B and C rotate around X, Y, and Z axes respectively. So I code my rotary axis as C, but it is possible to not use that convention by changing a parameter.
So in the your programming examples you wouldn't change the axes orientation, you simply tell the machine the cutter in in the Y axis by using G18 in the G code.
There is a program showing this in one of the links to my cloud previously. It's the one where it pretends to cut a spiral thread using a cutter in the Y axis and the C rotary table.Rather like a vertical lathe.
The next problem is that on our machines the cutter is usually attached to the Y axis, so it moves that way. The other 2 involve the table moving up and down and sideways.. On the typical Bridgeport of that era, the quill moves the cutter in the Z direction and the table moves back and forward and sideways. And yet you set up the program identically for both!
So the convention is that the DATUM is the work piece. So when you do the familiar right hand rule with your real hand, You place the back of your hand on the work piece whilst standing in front of the machine. And keep it stuck in the same place on the work piece as it moves.
Now look at where the cutter is moving relative to you hand:
If it is moving in the direction your thumb is pointing then it's moving positive X
If it is moving in the direction your index finger is pointing then it's moving positive Y
If it is moving in the direction your middle finger is pointing then it's moving positive Z
That works for all types of 3 axis machines.I have no idea how they label machines with 5 axes and seemingly infinite rotation axes.
In our case what seems counter intuitive is that for X+ the table will move left and for Z+ the table will move down.
Cheers,
David
