Strange pads on ceramic capacitors

It looks something has gone wrong with the clearance here. What can I do. There don’t seem to be any setting to control this.

The clearance might be ok, what happens if you turn off “F.Paste” layer?

The tolerance envelope seems to follow the inner purple line. I don’t use SMD at this point so I’m not sure what that is and why it is a different shape. Checking a few footprints in the libraries it seems it should be on the outer boundary of the pad.

Notice that @Sparky_Labs has swapped the colors of F and B copper. Not very good for sharing screenshots to those who use the defaults.

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Yes usually this is the case but i have a mix of pads like this and pads where the copper pour goes right round the outside.

Yes the PCB layer colours are swapped.

I think you are right. If i turn it off it looks right. But why is the paste too big on one side? I don’t think it is even possible to set it deliberately like that.

That is odd, maybe a bad footprint?

It came out of the kicad libraries.

Unfortunately, that doesn’t necessarily mean it is without faults!

It is more likely that the projects paste clearance is set wrongly. Most likely a confusion of what positive vs negative numbers mean.

I’ll have a look at the settings later. I have not changed anything but oddly some are OK some are not so I think it may be component settings.

If you use nightly then it could also be a difference in behaviour compared to the stable version. The official lib is only tested against stable so there is no guarantee at all that it works in a development version.


Generally: I would be really surprised if the problem is in the ceramic caps footprints to be honest. They are all setup to take the project clearances (The reason i am certain about this is because most of them are generated by a script i wrote and that script does not even support overwriting the paste clearance). So it could be that the once where you do not see the “problem” are really the footprints setup strangely.

Well I took these out of KiCad about 6 months ago and kept them as my own set of libraries. I have not modified them just kept my own copy.

Ehm… can somebody please explain to me how SMD BACK layer pads connect to FRONT layer copper traces?

@Sparky_Labs … your colors are off and confusing.
Do you mind changing them to something more common?
Find a file called ‘pcbnew’ in the kicad ini file folder… other files in there are (kicad, kicad_common, eeschema, fp-lib-table, sym-lib-table…).
Copy the ‘pcbnew’ file (to be able to restore to your personal setting) and then edit the following fields to these values and grab another screenshot (with x.Adhes, x.Paste, x.Mask deactivated):

ColorPCBLayer_F.Cu=rgba(132, 0, 0, 0.800)
ColorPCBLayer_In1.Cu=rgba(194, 194, 0, 0.800)
ColorPCBLayer_In2.Cu=rgba(194, 0, 194, 0.800)
ColorPCBLayer_In3.Cu=rgba(194, 0, 0, 0.800)
ColorPCBLayer_In4.Cu=rgba(0, 132, 132, 0.800)
ColorPCBLayer_In5.Cu=rgba(0, 132, 0, 0.800)
ColorPCBLayer_In6.Cu=rgba(0, 0, 132, 0.800)
ColorPCBLayer_In7.Cu=rgba(132, 132, 132, 0.800)
ColorPCBLayer_In8.Cu=rgba(132, 0, 132, 0.800)
ColorPCBLayer_In9.Cu=rgba(194, 194, 194, 0.800)
ColorPCBLayer_In10.Cu=rgba(132, 0, 132, 0.800)
ColorPCBLayer_In11.Cu=rgba(132, 0, 0, 0.800)
ColorPCBLayer_In12.Cu=rgba(132, 132, 0, 0.800)
ColorPCBLayer_In13.Cu=rgba(194, 194, 194, 0.800)
ColorPCBLayer_In14.Cu=rgba(0, 0, 132, 0.800)
ColorPCBLayer_In15.Cu=rgba(0, 132, 0, 0.800)
ColorPCBLayer_In16.Cu=rgba(132, 0, 0, 0.800)
ColorPCBLayer_In17.Cu=rgba(194, 194, 0, 0.800)
ColorPCBLayer_In18.Cu=rgba(194, 0, 194, 0.800)
ColorPCBLayer_In19.Cu=rgba(194, 0, 0, 0.800)
ColorPCBLayer_In20.Cu=rgba(0, 132, 132, 0.800)
ColorPCBLayer_In21.Cu=rgba(0, 132, 0, 0.800)
ColorPCBLayer_In22.Cu=rgba(0, 0, 132, 0.800)
ColorPCBLayer_In23.Cu=rgba(132, 132, 132, 0.800)
ColorPCBLayer_In24.Cu=rgba(132, 0, 132, 0.800)
ColorPCBLayer_In25.Cu=rgba(194, 194, 194, 0.800)
ColorPCBLayer_In26.Cu=rgba(132, 0, 132, 0.800)
ColorPCBLayer_In27.Cu=rgba(132, 0, 0, 0.800)
ColorPCBLayer_In28.Cu=rgba(132, 132, 0, 0.800)
ColorPCBLayer_In29.Cu=rgba(194, 194, 194, 0.800)
ColorPCBLayer_In30.Cu=rgba(0, 0, 132, 0.800)
ColorPCBLayer_B.Cu=rgba(0, 132, 0, 0.800)
ColorPCBLayer_B.Adhes=rgba(0, 0, 132, 0.800)
ColorPCBLayer_F.Adhes=rgba(132, 0, 132, 0.800)
ColorPCBLayer_B.Paste=rgba(0, 194, 194, 0.800)
ColorPCBLayer_F.Paste=rgba(255, 255, 194, 0.800)
ColorPCBLayer_B.SilkS=rgba(0, 72, 72, 0.800)
ColorPCBLayer_F.SilkS=rgba(0, 194, 194, 0.800)
ColorPCBLayer_B.Mask=rgba(255, 255, 194, 0.800)
ColorPCBLayer_F.Mask=rgba(132, 0, 132, 0.800)
ColorPCBLayer_Dwgs.User=rgba(0, 0, 255, 0.800)
ColorPCBLayer_Cmts.User=rgba(194, 194, 0, 0.800)
ColorPCBLayer_Eco1.User=rgba(0, 194, 0, 0.800)
ColorPCBLayer_Eco2.User=rgba(0, 194, 0, 0.800)
ColorPCBLayer_Edge.Cuts=rgba(194, 0, 194, 0.800)
ColorPCBLayer_Margin=rgba(194, 194, 194, 0.800)
ColorPCBLayer_B.CrtYd=rgba(132, 132, 132, 0.800)
ColorPCBLayer_F.CrtYd=rgba(132, 132, 132, 0.800)
ColorPCBLayer_B.Fab=rgba(255, 255, 194, 0.800)
ColorPCBLayer_F.Fab=rgba(255, 255, 194, 0.800)
ColorTxtFrontEx=rgba(194, 194, 194, 0.800)
ColorTxtBackEx=rgba(0, 0, 132, 0.800)
ColorTxtInvisEx=rgba(132, 132, 132, 0.800)
ColorAnchorEx=rgba(0, 0, 255, 0.800)
ColorPadBackEx=rgba(0, 132, 0, 0.800)
ColorPadFrontEx=rgba(132, 0, 0, 0.800)
ColorViaThruEx=rgba(132, 132, 132, 0.800)
ColorViaBBlindEx=rgba(132, 132, 0, 0.800)
ColorViaMicroEx=rgba(0, 132, 132, 0.800)
ColorNonPlatedEx=rgba(194, 194, 0, 0.800)
ColorRatsEx=rgba(255, 255, 255, 0.800)

what do you mean more common? they are standard KiCad colours other than front and back being reversed, most packages I have used have green as the front and red irritates my eyes.

Did you forget to change the pad colors in the ‘Items’ list?
Way confusing. You can work like that?

Btw, can you attach the footprint in question?
I doubt that the paste is coming from the pad object, but instead is a separate object.

Still, I’d deactivate the layers you don’t need for layouting (Adhes, Paste, Mask).

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I had’t noticed those. Maybe that is the problem or maybe it is highlighting the problem. I will have a look.

I have gone into the board setup and it has 5% solder paste ratio clearance. If I set it to 0 the shape perfectly aligns to the pad rather than spill over on one side. Setting it to -5% it looks more sensible. I think maybe the default should be negative rather than positive.

The default is 0. (So neither positive nor negative)

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