Having problems with tool offsets, machine will only work with them turned off
I'm having a problem trying to get my machine running multiple tools with tool offsets. This is a Boss 5 Bridgeport converted to Mach 3, the machine works fine for parts cut with a single tool zeroed on the stock top. Now I need to incorporate tool changes, here is the procedure I used to set up the tool offset table: I home the machine to machine zero, then I assembled tool 1 with a 1/2" dowel pin as reference tool and measured from the gauge line to tip at 3.6825 using a height gauge on a surface plate with a taper fixture (the 3.6825 is the net length after deducting the height of the fixture) I measured the rest of the tools the same way and then entered the lengths in the tool length column of the tool table and hit enter and apply for each entry.
The first tool I need is tool 12, a face mill that measures 3.2" from gauge line to tip. I zero that face mill to the stock top with a sheet of paper and enter zero on the main program page for mach, z axis, work (not machine) coordinates. (For the purposes of this exercise I am not concerned with the thickness of the paper). I load the g code, regenerate toolpath, press cycle start and the z axis rises to the z axis tool change position of machine coordinate z = zero. Mach says press cycle start after tool change. I already have tool 12 in there, so I hit cycle start but then immediately the z axis raises to the upper limit switch, triggering the estop. Note that the correct tool and associated offset is in the tool information spot on the program run page.
In troubleshooting this if I go to the offsets page and click tool offsets off (the green light off) before hitting cycle start after each tool change, the G code runs fine and there is no problem. I've looked at many videos and instructions,( most of which aren't very specific or gloss over what must be some critical detail) and can't figure out what I'm doing wrong, I'm sure the answer is right in front of me but its not sinking in. Any tips would be appreciated. I have only ever run this particular machine, which I converted and have minimal CAM experience but a lot of CAD...My understanding is that once ANY tool in the tool table is zeroed to the stock, any OTHER tool will have the correct reference because Mach, using the tool table, calculates the difference between the distance to the stock between the first tool that was zeroed and any other tool that gets called up- so why am I having this issue? here's a relevant portion of the g code if it would help:
N1 G20 G64
N2 (2 5FL FACE MILL)
N3 G91 G28 Z0
N4 G90
N5 T12 M06
N6 S3094 M03
N7 G90 G54 G00 X-2.1 Y-.8
N8 G43 Z.1 H12 M08
N9 G01 Z-.05 F5.
N10 G17 X0 F75.
N11 X5.75 F100.
N12 X6.85
N13 G02 Y-1.95 I0 J-.575
N14 G01 X5.75
N15 X0
N16 X-2.1 F75.
N17 G00 Z.1
N18 Z1. M09
N19 G91 G28 Z0
N20 G90
N21 (3/4 EM CRB 4FL 1-1/2 LOC)
N22 T04 M06
N23 S3560 M03
N24 G90 G54 G00 X-.185 Y-2.935
N25 G43 Z.05 H04 M08
N26 G01 Z-.2 F6.764
N27 Y-.2467 F27.0558
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