Reduce clearance of groundplane

Hi All,

I’m trying to reduce the clearance in the copper zone properties for the ground plane.
The values default to:
clearance: 0.508 mm
minimum width: 0.254 mm
pad connections: thermal reliefs
thermal clearance: 0.508 mm
thermal spoke width:0.508 mm

When I reduce those values, nothing changes on the board after clicking OK and when going back the copper plane properties, the default values are back with “net” on while first defined as GND.

Do I overlook something here?
Any clous would be appreciated.

Application: Pcbnew
Version: (5.1.12-1-10_14), release build
wxWidgets 3.0.4
libcurl/7.64.1 SecureTransport (LibreSSL/2.8.3) zlib/1.2.11 nghttp2/1.39.2
Platform: macOS Catalina Version 10.15.7 (Build 19H1519), 64 bit, Little endian, wxMac
Build Info:
wxWidgets: 3.0.4 (wchar_t,STL containers,compatible with 2.8)
Boost: 1.76.0
OpenCASCADE Technology: 7.5.3
Curl: 7.54.0
Compiler: Clang 10.0.1 with C++ ABI 1002

Build settings:

Press B to recalculate the zones

There are clearance properties of the zone itself, the net of the zone has a clearance and other nearby nets also have their own clearances.

Different zones can (and should) also have different priorities for their clearances.

You can try regenerating the zone boundaries by pressing the b key, but newer KiCad versions should do that automatically.

For a decent advice I need to know more. Maybe a screenshot combined with a note of which clearance you want changed where helps. But for easiest diagnosis an upload of you project gives us the most info.

Thanks for the replies. Unfortunately B and command-B didn’t work.
The goal is to get the grounded pins of the VQFP closer to the ground plane.
I can’t upload the project as new users are not allowed to do :frowning:

That’s an annoying anti-spam feature which gets automatically lifted if you read enough forum topics or gain “experience” otherwise. I think you need half an hour of “viewing time” for that.

You can upload (at least) one screenshot / picture per post.

That sounds as if it has something to do with thermal reliefs.

Try now. and 20 more…

Hi Paul,
Even when I halve all parameters nothing changes.
Sorry for the question, but how do I post? I geuss the below is useless.

whaw, it wasn’t :slight_smile:
Each forum has it’s habits

Try this:

Edit the properties of your copper zone and set “Pad connections” to “Solid”

(Also press b again after the dialog is closed (just to be sure))

No luck, nothing changed with the following settings

and when clicking on the settings all went back to the default

You have written that also in your first post. I think here is the problem source. But I don’t know what can be the reason for.

I needed to do something but had the same/similar problem. I solved it by doing some homework/testing… The solution is not apparent but, it’s right in front of your eyes…

This (the settings) may suggest a starting point…

Just did a reinstall of the software V5.1.12: no cure however
Is there any else on the forum facing the same problem?

… the Hint is understanding the effects of changing Clearence, Min Width, Thermal Cleraance and Spoke values - once understood, you’ll come the solution…

EDIT _Added:
Once happy with all else on the PCB, make the changes as needed but DON’T Re-fill it!! That puts an additional Gap around it

Here are some examples of tweak a affects…

I have 5.1.10 for Windows. Few days ago I was looking if there is 5.1.11 but it wasn’t.
Now I see 5.1.12 is there. May be with .12 something wrong happened.

V5.1.11 has been bumped to V5.1.12 because version numbers are for free and it can avoid some confusion.

V5.1.12 is now also availabe on my linux box.

I have just installed 5.1.12 (Windows), opened one of my projects went into edition of GND zone and changed Clearance (from 0.25mm to 0.5mm). When I clicked [OK] button my zone was rebuild correctly.
While finishing that sentence I suddenly noticed that I have [OK] and [Cancel] buttons reversed then you (OK is on the left). And behavior you describe looks like when pressing [Cancel].
Is it possible that your buttons just get wrong texts on them?
Try accepting your changes by clicking [Cancel] :slight_smile:

The order of the [OK] and [ Cancel ] buttons are either directly decided by your OS, or KiCad deliberately changes the order to conform with “good practice” guidelines for the different operating systems.

So that the order of those buttons are different is nothing special, but there is nothing wrong with double checking if there is some kind of bug in this area.

The reason for aways returning to the default values was my mistake: one have to click on the edge of the zone, not inside the zone. But for some reason I tumbled into another problem. When pressing B a message pops up for a fraction of a second telling “removing insulated(?)/isolated(?) copper islands” and another message about polygons…
What I also noticed when B is pressed the ratsnest disappear but nothing is filled.
Any idea what is happening here???

As you gave Copper Zone Properties screenshot I assumed you got it by clicking on the zone edge. How clicking inside the zone you got that edit window? I can’t figure out how to do that.

That means that KiCad filled the zone but it got several separated parts (islands). Some of them had not connection to any pad with the net specified for zone so as not being connected with anything they were removed (unconnected part of copper at PCB is not a good thing I think).

May be you have switched off showing the filled areas in zones so they are done (so ratsnest changed) but not showed.