Progressing a little further, I'm now wanting to cut a circular 'pocket' - well the outside - and I'd like it to be 22mm deep.
The top of the work is at Z= -52 so starting a Z= -51 to provide a 'Z lead-in' so that there is no plunge entry, I'm using G2 with the Z parameter changing at each pass by 2mm I want to get down to Z = -74 but, in the simulation, I'm getting a [Soft Limits] error when Z is below -71
This is the program I'm simulating :
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O0010 (Bore ready to Thread Mill 80 x 3.NC)
N10 (Author - JG - 24 July 2020)
N20 (for Denford MicroRouter Compact under Mach3 V2)
N30 (Thread Milling 80 x 3mm - bore = 76.75 - R= 38.376)
N40 (T3 D=8 Flatt End Mill to remove centre)
N45 (T4 D=24.32 Thread Mill cutter)
N50 (units mm)
N60 (X & Y 0 in MACHINE centre)
(X Min = -200, X Max +200)
(Y Min = -100, Y Max = +100)
(Z Max = 0 at top Z Min = -100)
N100 G17 G21 G00 (set up XY Plane & Metric - fast traverse)
N110 X34.0762 Y0 Z-51 (move XY & Z - Determine Z by reference to work)
N120 S8000 M3 (set spindle speed & start spindle)
N130 F3000 (set feed rate - simulation )
N140 G2 I-34.0762 J0 Z-52 (cut Circle about 0,0 feeding Z 2mm)
N150 I-34.0762 J0 Z-54
N160 I-34.0762 J0 Z-56
N170 I-34.0762 J0 Z-58
N180 I-34.0762 J0 Z-60
N190 I-34.0762 J0 Z-62
N200 I-34.0762 J0 Z-64
N210 I-34.0762 J0 Z-66
N220 I-34.0762 J0 Z-68
N230 I-34.0762 J0 Z-70
N240 I-34.0762 J0 Z-71
N250 I-34.0762 J0
(N260 I-34.0762 J0) (Cut flat bottom NO Z change)
N1450 M05 (Turn spindle off)
N1500 G00 X0 Y0 Z0 (move tool at fast rate to 0 0 0)
N1510 M30 (Close Program)
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The error appears if I set Z in N240 to -72 -- I would expect (in theory) to be able to go to -100, there will of course be other factors such as tool length that will preclude that, but I'm not setting a tool Nº which might confuse the issue anywhere.
A separate question - after each rotation (line of G-Code N140 - N240) there is a tool 'dwell'; can this be eliminated so that the program simply runs a continuous cycle ?