Tool Center Point Issues

    I am currently using a Fanuc ArcMate100i with a R-J3 controller. It is an older robot/controller and I have just been introduced to it last week. Mounted on the robot face plate is a torch holder which holds a TIG torch. I am trying to make the sharpened tip of the tungsten the tool center point. The tungsten is at a ~45 degree angle to the face plate pointing away from it. The tip is near the center of the face plate but it is not dead center. I am trying to program a ~1/2" diameter circular weld with a circular move, however, the tool center point for whatever reason is not at the tip of the tungsten.

    I have tried setting up the tool frame using the six point method several times with no luck. I am making Approach Point 1 and the origin point where the tip of the tungsten touches the reference point with the tungsten parallel to the Z axis. For Approach Point 2, I rotate J6 in JOINT 180 degrees and jog in world so that the tip of the tungsten is back at the reference point. Then I return it to the origin. For Approach Point 3, I rotate J4 in WORLD about 60 degrees, jog the tip of the tungsten to the reference point, and then move it back to the origin. Then I program my X and Z offset points. When I select the new tool frame and go into TOOL coordinates, it is obvious that the tip of the tungsten is not the TCP after attempting to rotate.

    My question is whether I'm not setting up the tool frame correctly or if there could be other issues with this robot.

    I've attached a napkin drawing of the tool situation.

    Which Tool Frame are you teaching? And then which one do you use for programming? Make sure that it is the same number. You can quicklky switch between the Tool Frames by pressing SHIFT + COORD (a popup window will be displayed) and then moving to Tool with arrow keys and pressing a desired numeric key.

    I suggest use the THREE POINT METHOD, then input directly the tool orientation values (W,P,R)
    Use -45 for P (Pitch), to align the tool Z axis with the center of the torch
    keep the rest 0

    IF your torch is NOT exactly at 45 degrees the torch will spin around the imaginary center when rotating in tool frame (z)
    Vary the angle until the torch rotates around it's center

    IF you want to change the approach direction, you must rotate it 180 degrees (W=180), that is: tool move away form the part in tool frame +Z
    Keep Roll =0

    USURP_UR: I made sure to do that.

    robotero: After using the three point and adjusting to 45 degrees P, none of the three rotational axes are correct yet, although the y rotation is close.

    bidzej: I did that with no success.

    X,Y,Z follow the right hand convention: close your right hand, then extend ONLY three fingers
    Index finger points in the X direction
    Middle finger points in the Y direction
    Thumb points in the Z direction

    According to your sketch and frame convention:

    Z is the axis running at the center of the torch
    X is at 90 degrees (X and Z reside in the plane of the tool)
    Y is perpendicular to the plane tool

    Still you have to options to define Z+ upwards or downwards

    minus 45 degrees SHOULD work for a tool like the one you sketched

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