Arc resolution - StepUp DXF to footprint


I’m drawning a footprint following the steps:

  • Draw a DXF using LibreCAD
  • Import the DXF it into FreeCAD
  • Rename the pad types
  • Export using StepUp

I know the etching process is not too precise, but is there a way to have more segments to form an arc in the process of creating a footprint?

The pad is small I know(0.28mm), but is not looking nice at all:

The DXF is fine:


The files:
VQFN16.dxf (36.2 KB)
footprint_stepup_kicad.FCStd (100.5 KB)
BQ24650.kicad_mod (7.2 KB)


:boom: You are now a ‘basic’ user. Upload away. :wink:

1 Like

you are talking of 6 segments in a 280um pad… are you sure you need a better resolution?
ATM the only way to improve the discretization is modifying the code and changing the quasideflection value in the discretization function.
An other approach would be to allow arcs in polylines pads in kicad format … I remember there was a discussion about it…

It is not that I need, but it would be nice to have a better looking footprint…

Is there a reason to not have a better resolution? I think these segments would be visible on the physical board without too much magnification… wouldn’t it?

the tool internally is using a parameter to auto adapt the discretization of the curves… you can increase the quality changing this parameter, but this will increase the number of segments, increasing a lot the file size in many user cases.

As I said a better option would be to ask kicad devs to add arcs to polylines format in i.e. (fill) zones and pads.

I wouldn’t think so… 6mils is a typical minimum trace in a standard pcb which mean about 150um … then your curve would be quite near the pcb fabrication resolution

You are right, it will be difficult to see that the arc is not perfect in my case.

About the discussion with the devs, do you know if there is a plan to implement the arcs?

Maybe here: But TBH I’m not sure how this would work. KiCad already supports different kinds of arcs as primitives. The problem is that it internally seems to convert them to segments or polygons. Just look closely how rounded rectangle pads work.

EDIT: that’s from 5.99, which is the only relevant version anyways because no new features will be added to 5.1.

This topic was automatically closed 90 days after the last reply. New replies are no longer allowed.