Torch Not Piercing, then off mid-cut

Hello all, another first timer here. I’ve dug through historical posts and haven’t found the answer.

Setup: Crossfire Pro with RazerCut45, THC and return to home switches, two inline air driers, ~5CFM air flow. Dell 5300 running FireControl. G-code generated from Fusion 360.

Problem: G-code runs, torch fires up, but does not pierce, plasma power steadily decreases through cut and turns off. What’s odd, is that I’m using the same G code I was able to cut ~30 previous parts without issue. I’m cutting 11g mild steel. Previously with 65IPM, 40 amps, I got decent cuts with limited dross. Ground is directly to the 11g sheet.

THC testing passes. Voltages are within parameter.

I ran the code with the computer on battery; no change in failed cut.

G Code Sample:
(v1.6-af)
G90 G94
G17
G20
H0

(2D Profile20)
G0 X-0.005 Y2.5975
G92 Z0.
G38.2 Z-5. F100.
G38.4 Z0.5 F20.
G92 Z0.
G0 Z0.04 (IHS Springback + Backlash)
G92 Z0.
G0 Z0.15 (Pierce Height)
M3
G4 P0.5
G0 Z0.063 (Cut Height)
H1
G1 Y2.4975 F65.
G1 X-0.0048 Y2.496 F65.
G1 X-0.004 Y2.4946
G1 X-0.0029 Y2.4935
G1 X-0.0015 Y2.4927
G1 X0. Y2.4925
G3 Y2.6375 I0. J0.0725
G3 Y2.4925 I0. J-0.0725
H0
M5
G0 Z1.

G0 X-0.005 Y0.0575
G92 Z0.
G38.2 Z-5. F100.
G38.4 Z0.5 F20.
G92 Z0.
G0 Z0.04 (IHS Springback + Backlash)
G92 Z0.
G0 Z0.15 (Pierce Height)
M3
G4 P0.5
G0 Z0.063 (Cut Height)
H1

I’m going to try and upload a video of the problem.

My guess is your running out of air. 100 to 120 to plasma cutter. Gauge should read 70 to 75psi when cutting. If it drops below 60/65 the torch will not stay firing and turn off…

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