I was curious, so I did some poking at this…and got carried away with myself. I hope Rob doesn’t mind too much.
CC doesn’t have a separate directory for posts like meshcam, so no easy path there.
I dumped the strings from the executable, and found this.
DESCRIPTION = “Carbide3D-MM(*.nc)”
It implies it’s using the same post that MeshCam uses for Nomad. Rob is likely to have reused as much as he could from earlier projects…he wrote meshcam…probably uses the same toolpath engine…probably uses the same posts…I have meshcam…what does that post look like in meshcam?
So I read the MeshCam manual and looked at the carbide3d-mm post.
This is how it plunges:
PLUNGE_RATE_MOVE = “G0[SZ]”
PLUNGE_RATE_MOVE = “G1[Z] [FP]”
[FP] Plunge feedrate
[SZ] Safe Z height
It uses the “rapid” rate (G0) until it reaches the safe Z height (ie. where it expects there to never be any material) then slows and uses the plunge feed rate (G1…FP).
That’s clearly not what you’re getting though. So I kept poking, because now I was much more curious. I know the meshcam post for nomad works this way, I’ve used it many times.
I looked at the Shapeoko post in meshcam. It has no plunge statement. That’s interesting because it’s an optional statement in the post according to the manual. If it’s not there, it just uses the “FEED_RATE_MODE” statements. Which for Shapeoko post are:
FIRST_FEED_RATE_MOVE = “G1[X][Y][Z][F]”
FEED_RATE_MOVE = “[X][Y][Z]”
So I looked at the dumped strings again, and sure enough, you can see the strings for FIRST_FEED_RATE_MOVE, it’s values, they match up with both posts, but no PLUNGE_RATE_MOVE string. It looks like CC is actually using the “shapeoko” version of the post, not the “nomad” version of the post (both of which emit tool changes, by the way)
You’ll see exactly the behavior you describe - at the first move there will be a feedrate, and until the feed changes, the feed won’t be output again just like you describe. That also means you won’t get the rapid rate to the safe Z height, which can really slow down the whole cut.
On a lark, I tried setting CC to Nomad, to see if it made some adjustment to the post, and the output what still broken. It looks like it always uses the same post without changes which is what I expected, but means you can’t work around this by changing the machine type.
Because the posts aren’t separate in CC, you’ll have to ask @robgrz to fix it - looks like it just needs to use the Nomad post instead of the Shapeoko post. Maybe @WillAdams or @MrBeaver can put in a good word to help it along