Newbie- simple task attempt limited success

[George777]

I'm new to Mastercam and just learning how to do the simplest of tasks. Let me outline a simple procedure that I am attempting; but without complete success.

A piece of plastic 3.5 inches long and 2 inches wide by .25 inches thick with a rectangular pocket milled .15 inches deep at one end.

1... Using mastercam X, I created the geometry for the base piece of plastic and the pocket.
2... I selected the machine type as a Mill and the default, (I have a Taig mill)
3... I selected the Toolpath as a "pocket" and then filled all of the required dialog boxes
4... I verified the toolpath and did a backplot; everything looked fine.
5... I sent the file through to the post processor and the G codes were produced no problem.
6... I opened the G code file in Mach 3.

Now here's the rub, the "Program LImits" box in Mach3 shows limits extending way out to 10 inches on all axes. When I run the file the Taig axes run out to their limits and then stop. The pocket toolpath is a tiny little section of the Mach 3 display with a huge run from the origin to the toolpath start point. Obviously I've missed something.

[Mike Stevenson]

What do the numbers in the program look like? Are they too large or are they the numbers you would expect to see?

[George777]

Mike,

I looked through the G code and the numbers seem to reflect the size of the part that I originally created. My experience with G code is very limited; from what I can understand, the code sets up the parameters of bit size etc. and then seems to indicate an X axis point at 1.16 inches and Y at .5135 which is what I would expect for the size of the part in question. Nothing indicating a large movement by x or y axis. The code is quite short and listed below if that helps.

%
O0000
(PROGRAM NAME - TEST2 )
(DATE=DD-MM-YY - 01-08-08 TIME=HH:MM - 13:35 )
N100 G20
N102 G0 G17 G40 G49 G80 G90
/ N104 G91 G28 Z0.
/ N106 G28 X0. Y0.
/ N108 G92 X10. Y10. Z10.
( 1/4 FLAT ENDMILL TOOL - 235 DIA. OFF. - 0 LEN. - 0 DIA. - .25 )
N110 T235 M6
N112 G0 G90 X-1.1696 Y.5135 A0. S2139 M3
N114 G43 H0 Z.25
N116 Z.1
N118 G1 X-1.0115 Z.0917 F6.42
N120 X-1.2615 Z.0786
N122 X-1.0115 Z.0655
N124 X-1.2615 Z.0524
N126 X-1.0115 Z.0393
N128 X-1.2615 Z.0262
N130 X-1.0115 Z.0131
N132 X-1.2615 Z0.
N134 X-1.3615 Y.4135
N136 X-.4482
N138 Y.5892
N140 X-1.3615
N142 Y.7648
N144 X-.4482
N146 Y.9405
N148 X-1.3615
N150 Y1.1162
N152 X-.4482
N154 Y1.2918
N156 X-1.3615
N158 Z.1
N160 G0 Z.25
N162 X-.4382 Y1.3019
N164 Z.1
N166 G1 Z0.
N168 X-1.3715
N170 Y.4034
N172 X-.4382
N174 Y1.3019
N176 Z.1
N178 G0 Z.25
N180 M5
N182 G91 G28 Z0.
N184 G28 X0. Y0. A0.
N186 M30
%

[Mike Stevenson]

Please delete this line----> / N108 G92 X10. Y10. Z10. and the 2 occurrences of ----> A0. and be happy.

[cadcam]

Mike hit on the head. its the G92 line as you are not using the standard G54 datum offsets.

[George777]

Thanks guys,

Solved the problem, and learned a little too. Much appreciated.