Copper pours with rounded edges

[Cliff_Brake]

What is the best way to do complex copper pours in KiCad (using 6.0 pre-release)?

We need something with a shape that looks like the following:

One way seems to be to use a lot of points and fillet the corners – below is an experiment.:

Could probably make fillet’d corners work, but just want to make sure I’m not missing something.

[eelik]

The shape looks like it can be done with circular arcs and straight lines.

We are waiting for curves in polygons, https://gitlab.com/kicad/code/kicad/-/merge_requests/731. If I have understood correctly that includes zone outlines. @Qbort can tell more about that.

You can try something with the Margin layer. Zone fills avoid lines in that layer. Maybe it could be possible to use custom design rules with that.

[craftyjon]

Yes, some basic arcs in polygons support is coming, but in 6.0 there will not be any tools for drawing zone borders with arcs directly (meaning inside the Draw Zone tool). The way to get it will be to do the drawing in an external CAD tool and import DXF, or else to do the drawing using KiCad’s graphic line and arc tools and then convert to a polygon or zone.

[Cliff_Brake]

Thanks for the information – sounds like some nice options. Did not realize you can import a DXF and convert that to a pour – that should cover the complex cases.

[Qbort]

Following on from Jon’s comment, I’m mainly working on the backend which will allow support for polygons with arc segments. However no editing tools are likely to make the cut.

I have been generally struggling to get the feature working properly due to the clipping library (Clipper) only working with straight segments. It is therefore taking a lot longer than anticipated. I have an idea how to resolve and will spend some more time on it this weekend, hoping to make some good progress.

[paulvdh]

One of the many new things in KiCad-nightly V5.99 is that you can:

1. Draw some lines with end points matching.
2. Select them, Right click Mouse button and: Convert / Convert to Zone
   
   

However, that Convert option is missing if there is an arc present in the selection. It does seem like a simple way to add rudimentary arc support for drawing zones once the real problems are resolved. [Oops] Jon already wrote this.

Creating an arc approximation from line segments is doable at the moment, but it’s just a workaround and it works cumbersome. To do it:

1. Draw some random line. Here I made sure that (20,0) was the endpoint of the line.
   

2. Select the line segment, then right click and: Special Tools / Create Array [Ctrl + T], and draw a circular array. Here I used 10 instances with 10 degree’s between them:
   

3. Make sure to turn on: PCB Editor / Preferences / Preferences / PCB Editor / Editing Options / Magnetic Points / Snap to graphics: Always This snap to graphics only works with graphics on the same layer. I am not certain whether this is a bug or a feature.

4. Then select the “other” endpoint of each line segment and drag it to the start point of the next line segment. If KiCad finds the snap point, then it draws a white circle around it:
   

First time you do this, it is a bit of a struggle, but once you’ve done it a few times it can be done reasonably quick.