[Maarten Visser]

Hi folks,
I have this issue: I am milling with a 2mm flat endmill into silver. I set the Z feed to 20. But Madcam plunges the tool with a G00 move into the material, sometimes causing a tool break. This is what the code looks like, and the problem happens at line 9. I can manually add a G01 in between, but why does Madcan not honor the Z feed speed?
I am thankful for you input.
Maarten

G00 G49 G40.1 G17 G80 G50 G90 G64
G21
(C3b plaat)
(vinger 2)
M6 T1
M03 S6000
G01Z5.000
G00X-2.770Y-0.818
Z4.060
Z-1.772
G01Z-2.472 F20

[wendtmk]

G00 and G01 are modal. They stay in that mode until you change between them.

[Superman]

I don't use Madcam... but...
What is your defined "TOP of Stock" ?.... & your "Clearance" & "Retract" levels ?

Your work Z zero should be where you have it on the PC (normally the top of your part)
The top of your material would then be the same,(more if you have a facing cut).
Feeding in should start from the retract level going to the "TOP of Stock" minus any depth cuts you have set.

What you set in the PC, dictates what quality of NC code that is produced that controls your machine

[Maarten Visser]

I have defined 0;0;0 as top of stock, this works easiest in Madcam. Clearance is set at 3mm and retract I dont know. But madcam lets me specify a "safe Z" which I set at 5mm. As you see in the code, there are no F command, even though I set the speeds in the Madcam tool library.
best regards, Maarten

[Superman]

G00 G49 G40.1 G17 G80 G50 G90 G64
G21
(C3b plaat)
(vinger 2)
M6 T1
M03 S6000
G01Z5.000
G00X-2.770Y-0.818
Z4.060
Z-1.772
G01Z-2.472 F20

Looking deeper at your code layout
Your post seems to output a Z clearance move before a XY move, this seems in the wrong order. And it seems to be programmed manually ( your spacing formats, no Feedrate on a G01 move)

... what happens if you have clamps or vice jaws that are higher than your work zero ?

Is it possible that the operation parameters in MadCAM are set incorrectly (ie incremental/absolute clearances, depth of cut settings, finishing cycle instead of roughing ) ?

Something doesn't look right with what has been posted.

[Maarten Visser]

Hi Superman, you write: ". And it seems to be programmed manually ( your spacing formats, no Feedrate on a G01 move)..." Well this is the unedited code that Madcam genereates. (I may point to you that we are on the Madcam support forum within Cnczone). As for clamps and such Mach3 shows me visually where the tool is going, so I keep all else out of the path. I am not aware of any of the setting faults you mention.
best regards, Maarten Visser

[Superman]

I'm just looking at the NC code and what needs to be set in the CAM to create the correct NC code.

The machine just executes the code line by line. It's easy to follow what is expected to be written.
Ie -toolchange
-rapid to XY position
-rapid to Z clearance
-rapid to retract place(can be same as clearance)
-feed into material
-feed XY (& sometimes Z)
-retract to above material

What points me to some info being manual is the 1st G01 line does not have a feedrate, hell, the whole line shouldn't even be there. You need a G01 on the Z-1.772 with F20. As this is the line that makes the tool plunge into material.

You have to find what in the MadCAM operation settings that controls movement from Z4.060 to Z-1.772 ... as it needs to output a feed move with feedrate, not a rapid.

[williamsmotower]

When setting your XYZ right before post-processing, use something like 0,0,20.

It's another safe Z option separate from safe Z