Pads joined in soldermask layer in gerber files
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
KiCad |
Fix Committed
|
Medium
|
Seth Hillbrand |
Bug Description
Application: pcbnew
Version: 4.0.6 release build
wxWidgets: Version 3.0.2 (debug,
Platform: Windows 8 (build 9200), 64-bit edition, 64 bit, Little endian, wxMSW
Boost version: 1.60.0
Curl version: libcurl/7.52.1 OpenSSL/1.0.2k zlib/1.2.11 libssh2/1.8.0 nghttp2/1.19.0 librtmp/2.3
Reproducible on platforms: Windows 10 and Gentoo Linux confirmed (Kicad 4.0.4).
Steps to reproduce:
1. Create new layout in Pcbnew.
2. Add housings TQFP32 7x7mm 0.8mm pitch footprint from the standard library.
3. Rotate footprint by 45degrees
4. Set soldermask clearance to 0.05mm and minimum width to 0.15mm.
5. Plot to gerber.
6. Open the solder mask layer in gerber viewer.
Actual result: Several pads will have been joined in the soldermask layer.
Expected result: No pads are joined in the solder mask layer.
I believe that the issue is caused by a missing epsilon value when computing the soldermask on a rotated component. It so happens that the footprint has 0.55mm wide pads and 0.8mm pitch, if you add it up with the clearance and minimum width you get: 0.8mm === 0.55mm + 2*0.05mm + 0.15mm and I believe that it's a truncation error in the floating point math used to compute the final solder mask.
For now I'm working around it by using 0.0499999 solder mask clearance.
Changed in kicad: | |
importance: | Undecided → Low |
status: | New → Triaged |
Changed in kicad: | |
milestone: | none → 6.0.0-rc1 |
importance: | Low → Medium |
I just experienced this issue as well (in newest nightly). but for me it was simply a matter of setting the minimum width to something lower than 0.25mm. Some visualization of the joined soldermask in PCBNew and perhaps also the 3D viewer would be really handy as well. Should this be a seperate issue?