I have a 1995 Leadwell V40 with a Meldas M50 control.

It was running fine yesterday... today I load a part in and start the program - the first thing it does is a tool change. The machine moves the Z axis all the way up... the spindle orients... the tool changer moves over... then it just stops. The next step *should* be that the tool unclamps... then the Z moves up higher, the carousel rotates, then the Z axis comes down, the tool clamps, then the carousel moves back. But it stops just before the tool is supposed to unclamp.

I can't figure out what is wrong. There is no error message on the screen. I have tried doing a tool change in the MDI and it does the same thing. I can move the table fine, I can move the Z axis fine. All axes home perfectly. If I push the tool unclamp button, the tool comes in and goes out fine. Everything seems to be working but it won't change tools.

I was poking around in the control and I noticed program #9001 is called "TOOL CHANGE MACRO". The contents of this program are:

G4;
T#20;
G4 P.200;
IF [#1000 EQ1] GOTO4;
IF [#1001 EQ1] GOTO4;
M66;
G80;
#131 = #4003;
#130 = #4006;
G91 G28 Z0;
G49;
N1 IF [#1002 EQ0] GOTO1;
G30 Z0 P2;
N2 IF [#1003 EQ0] GOTO2;
G28 Z0;
G#131;
G#130;
N3 IF [#1004 EQ0] GOTO3;
N4 M67;
M99;
%

I am not getting any alarms on the servo amps either.

I did notice that if I click on the command menu to show the current program, the cursor is flashing on the "N1 IF [#1002 EQ0] GOTO1;" line. I honestly don't know what that macro really does - I recognize some of the G codes but that's about it.


Any ideas? I am hoping this is something simple. Of course, I have customers screaming for parts that I can't make

Thanks!
Mike