Pocket Cut Depth

[FS-Racine]

Any thoughts on why my pocket cut has one pass that's deeper than the rest? Not sure if it's the machine or VCcarve.

CRV file is here:
https://drive.google.com/file/d/1HvyTBb ... sp=sharing

[Adrian]

That's an odd one. Looks like it started to lose steps on the clearance toolpath as it looks like there are slight deeper cuts leading up to that one. Usual reason for that is nearly always a mechanical issue with the machine.

[TReischl]

A rule that most of us have learned is:

If the preview looks correct but the machine cuts something off it is a machine issue about 99.999% of the time.

Loose bit.
Lost steps.

Lost steps is the trickier of the two. They can be caused by all sorts of things. Load on cutter too high. Electrical interference. Loose mechanical connection (usually a coupler). Etc.

[FS-Racine]

I ran the same cut on a new sheet, exactly the same result. This is foamed pvc plastic, the bit is going through it like a hot knife through butter.

[Rcnewcomb]

any thoughts on why my pocket cut has one pass that's deeper than the rest?

I generated the toolpaths and looked at the G code and did not see a problem with the Z.

What post processor are you using?

Have you looked at the G code in Notepad? All you are looking for are the Z values

On the first line it jogs to 1.28" above the machine bed
On the second line it jogs to X 0 Y 0
On the third line it moves the Z to 0.68" above the machine bed
On line 4 it moves the Z down to 0.355" above the machine bed.
(Your material is 0.48" and the pocket depth is 0.125", therefore it moves to 0.355")

Code: Select all

G0Z1.2800
G0X0.0000Y0.0000
G0X6.7647Y5.9342Z0.6800
G1X6.7647Y5.9342Z0.3550F50
G1X6.7811Y5.8682Z0.3550F100

[martin54]

I ran the same cut on a new sheet, exactly the same result. This is foamed pvc plastic, the bit is going through it like a hot knife through butter.

Don't rule out lost steps because the material is easy to cut, lots of reasons for lost steps

As Ted has said if the toolpath preview looks correct then the problem is most likely to be either your control software or a machine issue, either mechanical or electrical

[FS-Racine]

any thoughts on why my pocket cut has one pass that's deeper than the rest?

I generated the toolpaths and looked at the G code and did not see a problem with the Z.

What post processor are you using?

Have you looked at the G code in Notepad? All you are looking for are the Z values

On the first line it jogs to 1.28" above the machine bed
On the second line it jogs to X 0 Y 0
On the third line it moves the Z to 0.68" above the machine bed
On line 4 it moves the Z down to 0.355" above the machine bed.
(Your material is 0.48" and the pocket depth is 0.125", therefore it moves to 0.355")

Code: Select all

G0Z1.2800
G0X0.0000Y0.0000
G0X6.7647Y5.9342Z0.6800
G1X6.7647Y5.9342Z0.3550F50
G1X6.7811Y5.8682Z0.3550F100

Axiom HHC CNC.pp, attached.

[Rcnewcomb]

I generated the code using the post processor you supplied. The output is metric, but the Z numbers are absolutely correct. It is moving the Z to 9.017mm above the machine bed, which is 0.355 inches.

I checked both pocket files since you have it set up as a tiling job. There is no problem with the code that VCarve is generating..

You are dealing with an issue with the controller, the machine, or the hold down.

Code: Select all

(Filename:  T1_Pocket 1 [Clear])
N10M03S18000
(Pocket 1 [Clear])
N30G00X171.823Y150.729Z17.272
N40G1X171.823Y150.729Z9.017F1270.0
N50G1X172.239Y149.051Z9.017F2540.0
N60G1X174.153Y150.051Z9.017

[FS-Racine]

I generated the code using the post processor you supplied. The output is metric, but the Z numbers are absolutely correct. It is moving the Z to 9.017mm above the machine bed, which is 0.355 inches.

I checked both pocket files since you have it set up as a tiling job. There is no problem with the code that VCarve is generating..

You are dealing with an issue with the controller, the machine, or the hold down.

Code: Select all

(Filename:  T1_Pocket 1 [Clear])
N10M03S18000
(Pocket 1 [Clear])
N30G00X171.823Y150.729Z17.272
N40G1X171.823Y150.729Z9.017F1270.0
N50G1X172.239Y149.051Z9.017F2540.0
N60G1X174.153Y150.051Z9.017

Hi Randall, thanks for looking into this for me - it's repeatable, I cut another sheet with exactly the same result.

[TReischl]

Hi Randall, thanks for looking into this for me - it's repeatable, I cut another sheet with exactly the same result.

Here is the thing, machine issues quite often are repeatable.

Takes a while to understand that if the machine is not being commanded to do something it isn't a software issue. G code is mysterious to a lot of people so it is normal to blame that which we do not understand.

Put your control into block by block mode (single step). Execute the program. You can cut air. Keep an eye on the Z axis readout. Now I am not a betting man but I would bet a dozen donuts that the Z goes to the programmed depth, the readout does not change but the Z changes position.

Or, you can think of it like I do. Since there is nothing in the g code to be changed no one is going to change the software.

[Rcnewcomb]

FS-Racine,
Have you posted this on the Axiom forum? I think that is the next step for support since we have ruled out any issue with the code Vectric is generating.

[Rcnewcomb]

I found your thread on the Axiom forum here.