SMD components - ground plane


I am new to KiCad and I have a problem with my PCB layout. Most of my components are THT but 4 capacitor which are SMD. When I make Vcc plane, everything is good, but when I make ground plane those 4 capacitors are included in ground (not visible when I fill zone). I tried a lot of ways to get it right but I just couldn’t. I also tried to look for solution and had a hard time finding it.

I’m not sure what you are saying but the red pads are on the top of the board and the green zone is on the bottom so they aren’t connected. You don’t see clearances around them like you do for the THT pads because those are on both layers.

The best way to get more insight into what the board actually looks like (top and bottom) is to open the 3D viewer with [Alt + 3]. (Hopefully all your components have the right 3D models associated with them).

After that, learn to use the layers manager on the right of the screen.
You can turn individual layers (or groups of layers with the right mouse button) on or off.
By double clicking on the small colored rectangle you get a color chooser where you can also set transparency of layers.

So it is normal for SMDs not to see clearances when I fill ground plane?

SMD pads also have clearances, and you can see them, but you are looking at a double sided board at the moment. From your screenshot I can not see what your board looks like. You can press [PageUp] or [PageDn] to look at the Red (front / top) or Green (back / bottom) copper layer.

There is also a very well known limitation in KiCad.
The boundaries of Zones are not updated automatically, because it is quite compute intensive. Just move any of your THT components, and you’ll see it will leave big holes at the old position, while the new position does not seem to have a clearance around the pads. Then hit [b] to re-compute the zone boundaries, and everything is all-right again.

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The ground plane is not on the same side of the board as the SM devices. You will not see a clearance in the green for the red pads. If you create a ground plane on the top (red) you will see the clearance in that plane.

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You might want to read: How to create a power plane (using zones)

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Thank you all, it was kind of a stupid question I guess, it is very logical that surface mount on top will not be seen looking at the bottom of the board.

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Not a stupid question at all.
When you’re new to KiCad (or PCB design programs in general) it’s easy to get confused.
Especially if you do not realize you are looking at a double sided PCB and you’re looking “through” the PCB.

Add to that unfamiliarity with the layer colors and the UI and there are plenty of opportunities to get confused.

Chalk it up to ‘learning curve’. There’s a lot going on and it takes awhile to get comfortable with it all.

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