3d pocket not honoring roughing step-down

3d pocket not honoring roughing step-down

Anonymous
Not applicable
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Message 1 of 11

3d pocket not honoring roughing step-down

Anonymous
Not applicable

I have a problem with some of my 3d pockets not honoring the roughing stepdown.  Others work fine. I have no idea what is different between ones that work, and ones that do not.

 

Attached is a video showing my problem.  You can see that the pocket is 8mm deep, and my stepdown is set to 5mm.  But, when you look at the tool path or watch the simulation, it's taking more than the expected 2 steps to clear the bulk of the pocket.  There are also some deeper bolt holes in this pocket, but I'm not worried about those right now. 

 

Any suggestions?

 

Thanks.

 

 

    --- Carl

 

 

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Message 2 of 11

Anonymous
Not applicable

No one?

 

   --- Carl

 

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Message 3 of 11

LibertyMachine
Mentor
Mentor

Hmm. Would you be able/willing to share the .f3d file? There are a few things I'd like to play around with.

To share the .f3d: File > Export > Save to local folder. Return to thread and attach the file


Seth Madore
Owner, Liberty Machine, Inc.
Good. Fast. Cheap. Pick two.
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Message 4 of 11

Anonymous
Not applicable

Sure.  I'm not going to claim it's a brilliantly executed design - I am new at this.

 

If you look at the CAM setups in "Front-Inside-PanelCutout" and "Front-Outside-FeaturesOnly" you see the step down working as expected in the former, and taking much smaller steps in the latter.

 

 

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Message 5 of 11

LibertyMachine
Mentor
Mentor

No worries on the skill level. We all start somewhere and it's to be expected. As long as the desire is there to learn more, it seldom becomes a hindrance. These forums exist for the sole purpose of helping people develop their skills, so never feel like you can't ask a question.

 

Now, onto your part. Right off the bat, I want to make sure you know your 2D contour in the "Front Inside Panel Cutout" is cutting on the inside of the part. I suspect you want it on the outside. Go into the Geometry tab. You will have to zoom in, because the arrow you need to toggle is very close to the triad and zoomed out is almost impossible to see. So, zoom in to where you WCS is and you will see a separate red arrow. Clicking on it will tell the operation you are looking to cut on the outside.

 

 

As for the 3D pocket issue. I honestly have no idea. I've played with every setting I could think of. Maybe it's this. nope. Maybe it's that. nope. Even if I set all my stepdown parameters to full flute length, it still kicks out the same 4 depths of cut.

Maybe I'm the odd one out, but usually when I encounter an issue, I'll give it a few moments of trouble shooting and then quickly abandon that approach in favor of something else that I know will work. In this case, I know 2D Pocket will get me exactly what I want with no issues. Side note; You can also use Horizontal (in the 3D tab) with decent results. However, you will need to use the patch tool to cover the speaker mounting holes. The toolpath will just be going around the holes wasting time and likely not removing what is needed

 

So, 2D Pocket. Select the inner and outer diameters of the speaker holes and just the outer diameter of the 23mm holes

2D Pocket.PNG

Heights; set to "Selected Contour"

Turn on "Multiple Depths", set Max Stepdown to 5mm and "Use Even Stepdowns"


Seth Madore
Owner, Liberty Machine, Inc.
Good. Fast. Cheap. Pick two.
Message 6 of 11

pawelzwronek
Advocate
Advocate
I've spotet this bug some time ago. When u select <Flat area detection> in 3D Pocket clearing, F3 machine every pocket on every detected flat area in all pockets. So multiple stepdowns in only 8mm deep socket come from flat areas from others socket. My workaround is to disable<Flat Aread Detection> and enable <Machine Shallow Areas> and set <Minimum Shallow Stepdown> to e.g. 0.05mm. This is stepdown resolution F3 will machine every pocket.
Message 7 of 11

Anonymous
Not applicable

Ah. Good eye about the 2-d profile. I think I had the wrong contour selected.  I had intended to select the outline on the "projection" sketch.

 

Thanks for the tip on trying the 2-d pocket.  I thought I had tried that, but I guess not.

 

   --- Carl

 

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Message 8 of 11

Anonymous
Not applicable

Interesting.  Deselecting flat area detection fixed the step-down problem, but introduced others - like completely skipping some of the cutouts.

 

    --- Carl

 

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Message 9 of 11

Anonymous
Not applicable

Ug.  Well, the 2-d pocket approach does seem to work around the bug. But, Oi! I have to make over 50 selections vs about 6 for the 3-d approach, and get one of the bolt holes wrong and it seems to go all wacky and do something like plane out the back of the part.

 

Best solution would be for the bug to be fixed.  I'm almost tempted to live with the step-down problem during machining to save the time and frustration of making the 2-d pockets work.

 

Thanks All.

 

    --- Carl

 

 

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Message 10 of 11

Anonymous
Not applicable
Has anyone from Autodesk been alerted as to this bug? Is it in their bug database?
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Message 11 of 11

craptree4NU47
Enthusiast
Enthusiast

Thankyou so much, just wasted about an hour scratching my head over this one, your workaround fixed it!

 

Cant believe this issue still exists after 6 years!!

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