oval board cutout vs. copper pour

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Tomg
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Joined: 20 Jun 2015, 07:39

oval board cutout vs. copper pour

#1 Post by Tomg » 02 Mar 2017, 09:12

I ran across this interesting copper pour behavior when using a small, oval, Board Cutout shape in one of my patterns. Notice that the non-copper "ears" on each side of the oval cutout change size when selecting a different value for the Clearance setting. Just in case, I set the Line Width and Line Spacing to the smallest values allowed for maximum definition, but the oval's non-copper "ears" remained. Also notice that the rectangle and circular Board Cutouts do not exhibit this anomaly. I have attached the offending test pattern for your amusement.

-- 03 Mar 2017, 06:39 --

More inconsistencies are shown in the bottom illustration. The "native" column shows Board Cutouts created with the DipTrace drawing tool set. The "import" column shows Board Cutouts created with a separate 2D CAD program, saved as a DXF file and imported into DipTrace using its DXF Import tool. Even though copper pour islands are not the norm for Board Cutout figures, I thought I would enable them in the example on the right to show the circular peculiarity on each side of the imported oval shape. Also notice that there is an island inside the imported rectangle, but not the native rectangle. Perhaps this will be of some help in the troubleshooting process to find and fix what appears to be another flaw in the DXF Import and/or Copper Pour tools.
Attachments
test patterns.lib
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oval.gif
oval.gif (55.83 KiB) Viewed 339 times
board_cutouts.gif
board_cutouts.gif (27.89 KiB) Viewed 339 times
Tom

Alex
Technical Support
Posts: 3897
Joined: 13 Jun 2010, 23:43

Re: oval board cutout vs. copper pour

#2 Post by Alex » 03 Mar 2017, 03:19

Please right click on board cutout shape and open properties. Check point coordinates. The artefact in copper pour may appear if there are two points with the same coordinates. In that case, delete redundant point and update copper pour.

Tomg
Expert
Posts: 2028
Joined: 20 Jun 2015, 07:39

Re: oval board cutout vs. copper pour

#3 Post by Tomg » 03 Mar 2017, 06:39

Hi Alex,
I changed the import oval coordinates to make sure none of them are repeated or even intersect, then I resaved the pattern, brought it into the PCB and re-poured the copper pour. Unfortunately, the artifact remains.
Tom

arcsecond
Posts: 17
Joined: 06 Mar 2017, 16:13

Re: oval board cutout vs. copper pour

#4 Post by arcsecond » 23 Aug 2017, 13:53

How do you completely eliminate the gap between the cutouts (purple shapes) and the copper pour (red fill, in the image above)?

For certain cutouts I want the soldermask and copper to go right to the edge of the opening. I'm using the "PCB" as a front panel for a rackmount enclosure, there's no electrical connectivity on the board, so having the copper right up to the edge doesn't matter.

I've tried various clearance settings, island removal, etc – can't get the gap to disappear even when the settings are at the minimum values. The clearance always seems to snap back to 0.1 mm, even if I set it to zero.

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KevinA
Posts: 639
Joined: 18 Dec 2015, 08:35

Re: oval board cutout vs. copper pour

#5 Post by KevinA » 23 Aug 2017, 18:59

arcsecond wrote:How do you completely eliminate the gap between the cutouts (purple shapes) and the copper pour (red fill, in the image above)?

For certain cutouts I want the soldermask and copper to go right to the edge of the opening. I'm using the "PCB" as a front panel for a rackmount enclosure, there's no electrical connectivity on the board, so having the copper right up to the edge doesn't matter.

I've tried various clearance settings, island removal, etc – can't get the gap to disappear even when the settings are at the minimum values. The clearance always seems to snap back to 0.1 mm, even if I set it to zero.
I thought the edge clearance was a PCB shop mandated thing. "Minimum copper to board edge clearance 0.3mm" found under PCB capabilities of most(?/all) board shops

arcsecond
Posts: 17
Joined: 06 Mar 2017, 16:13

Re: oval board cutout vs. copper pour

#6 Post by arcsecond » 23 Aug 2017, 19:03

Hey, thanks. My question is about internal cutouts though (not the outer edges of the board, which is what I think that "board clearance" parameter refers to). I've ordered boards (using Gerbers generated from Diptrace) where there is zero clearance around mounting holes for example. Curious how to do the same thing with board cutout shapes such as rectangles, etc.

Alex
Technical Support
Posts: 3897
Joined: 13 Jun 2010, 23:43

Re: oval board cutout vs. copper pour

#7 Post by Alex » 25 Aug 2017, 01:49

Please open "Route->Route Setup" and change "Copper to Board Outline" value.

arcsecond
Posts: 17
Joined: 06 Mar 2017, 16:13

Re: oval board cutout vs. copper pour

#8 Post by arcsecond » 25 Aug 2017, 05:02

Thanks Alex, I set the value to 0mm and that solved the problem – much appreciated.

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