Fusion 360 z axis moving up too fast

hi, I am having a problem with fusion 360 using guffy’s post processor (for marlin) where the z axis moves up at the same speed as the xy feedrate, while the plunge feed rate is going down what I set it to. I am a new user so please forgive me for my copy pasted gcode.

using latest post processor and fusion 360 version.
bought all parts from v1 engineering website.

copy pasted only a small part of the gcode as the entire thing would be too big

Blockquote;Fusion 360 CAM 2.0.9009
; Posts processor: DIYCNC_Marlin20.cps
; Gcode generated: Friday, October 9, 2020 6:13:24 PM GMT
; Document: Twin-72 v1
; Setup: Setup1
;When using Fusion 360 for Personal Use, the feedrate of rapid moves is reduced to match the feedrate of cutting moves, which can increase machining time. Unrestricted rapid moves are available with a Fusion 360 Subscription.
; Ranges table:
; X: Min=38.537 Max=219.512 Size=180.975
; Y: Min=479.745 Max=1168.718 Size=688.973
; Z: Min=-19.5 Max=10 Size=29.5
; Tools table:
; T1 D=3.175 CR=0 - ZMIN=-19.5 - flat end mill

; *** START begin ***
M84 S0
G92 X0 Y0 Z0
; *** START end ***

; *** SECTION begin ***
;2D Contour1 - Milling - Tool: 1 - flat end mill
; X Min: 38.537 - X Max: 219.512
; Y Min: 479.745 - Y Max: 1168.718
; Z Min: -19.5 - Z Max: 10
; >>> Spindle Speed 18000
M3 S18000
M117 2D Contour1
G1 X40.124 Y479.745 Z10 F3000
G1 Z5 F300
G1 Z3 F300
G1 Z-1.95 F305
G2 X38.537 Y481.332 J1.587 F1270
G1 Y649.81
G1 Y650.445 F500
G1 Z-0.5 F1270
G1 Y655.12
G1 Z-1.95 F305
G1 Y992.709 F1270
G1 Y993.344 F500
G1 Z-0.5 F1270


This problem came through the forum in the last week. This issue is probably related to the changes Fusion 360 has made recently to the software for their personal license users. It is unclear if the bug is in Fusion 360 or guffy’s post processor. Other post processors have also been having problems after the Fusion 360 changes. Editing your gcode file and adding a M203 code for the Z axis was suggested as a short term solution. Here is a link to the previous posts on this issue: Problem with Fusion and Z feedrate

1 Like

Hi, I was the one having similar problems. My solution was to purchase licence for Fusion and now all speeds are as they should. It looks like Fusion bug to me.