How to Pocket Cut a Logo

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chrisb
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Re: How to Pocket Cut a Logo

Post by chrisb »

I had checked Final Depth before, as it was irritating: it showed "-1" although the value set was 9mm. No matter whether I set it to 9 or left it automatic, it didn't work.
After your post I checked the other parameters and found that Step Down was at 5mm. Changing it to 1mm the path is generated. The problem seems to be, that the first step down already exceeded the final depth.
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micksulley
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Re: How to Pocket Cut a Logo

Post by micksulley »

Brilliant! Thanks for your help.
chrisb
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Re: How to Pocket Cut a Logo

Post by chrisb »

micksulley wrote: Fri Jun 15, 2018 10:28 pm Brilliant! Thanks for your help.
Glad I could help and glad I found something to remember.
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GeneFC
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Re: How to Pocket Cut a Logo

Post by GeneFC »

chrisb wrote: Fri Jun 15, 2018 9:15 pm The problem seems to be, that the first step down already exceeded the final depth.
This may be unique to Pocket operations. Profile_Edges does not exhibit the same behavior. I selected the shape of the letters and did a Profiles_Edges operation with the Step Down set to 50 mm. A single path was created at the Final Depth, as it should be.

Probably a deficiency in the Pocket operation.

Gene
chrisb
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Re: How to Pocket Cut a Logo

Post by chrisb »

GeneFC wrote: Sat Jun 16, 2018 2:57 pm Probably a deficiency in the Pocket operation.
That's what I thought as well. So I thought that might be simple enough to find and searched the code in order to simply change the internal value of StepDown to something better. Well, searched a while and finally built a simple test case, with the same situation as the logo above:
- Base object's height 10mm
- Pocket ending at 9mm
- create Pocket from Shape

And everything is ok. I will have a third look at the logo, but for now I think Pocket_Shape is ok. It might handle some strange situations better, but I cannot describe these situations yet.
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chrisb
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Re: How to Pocket Cut a Logo

Post by chrisb »

I recreated the model from my previous post going a way closer to the op's logo:

- created Part->Cylinder
- created Sketch in XY plane
- turned Sketch 180° around Y axis. Without this step the following extrude cannot be made forward to meet op's situation.
- created draft object from Sketch
- downgraded to get a face
- moved face to z=9
- extruded 1mm forward, direction: normal to face
- subtracted extrude from cylinder
- created Job, leaving everything at default
- created Pocket from shape, leaving everything at default. Inspecting depths showed FinalDepth=-1mm as with op's model.
- Confirmed and path was generated as before

Conclusion: no problem in Path WB.
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GeneFC
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Re: How to Pocket Cut a Logo

Post by GeneFC »

chrisb wrote: Sun Jun 17, 2018 5:54 am Conclusion: no problem in Path WB.
I agree. I tried the pocket with a new model, and it worked perfectly. I guess there was something unusual about the original file that did not suit the Path and/or Pocket operations.

Gene
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