What is the state of complex pad stacks in 8.0?

Hello all,

I am using the latest 8.0.0-rc1-16-gfc62d36441 release build. I have converted designs and footprint+symbol libraries from OrCad to Altium to KiCad. I have succeeded in converting everything except for complex pad stacks. For example, a PTH via on a 2-layer board that goes from a circle on the top to an oval on the bottom. I see in the KiCad future roadmap that official support is still being worked on. But is there a workaround in the meantime?

Thank you all.

For the example you gave, you can add multiple pads (giving them all the same name) and overlap them in the footprint editor. Make the through-hole pad the smaller of the two (i.e. if the circle is smaller than the rectangle, make it a circular shape) and then make a SMD rectangle pad overlapping it.

In the case that you need custom shapes on inner layers, there is not a workaround available using the KiCad UI.

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This worked, thank you. I hope that KiCad gains padstack capabilities, it is one feature that has been present in commercial offerings for decades and represents a significant hurdle when trying to transition designs and libraries. As far as I can tell, this is the only remaining issue stopping a seamless transition from Altium to KiCad (Or in my case, from OrCad to Altium to KiCad).

Thanks again!

There is an open issue for this for already a few years, opened in 2019:

A lot of issues get created, and also closed on a monthly basis (200 to 300), but there are also quite a bunch of older and more complex issues that stay open for a long time. It would be very nice if you could find a can or a hat out of which to pull a few handfuls of extra KiCad developers :slight_smile:

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Thanks for sharing the open issue, seems like this is a challenge. I am certainly impressed with the rate at which KiCad has improved over the years. With the most recent release KiCad has gained native Altium importation ability, and this was instrumental in helping me import old designs. I agree with you, I wish I could just conjure up some extra developers!

It’s been years since I’ve used Kicad, but I believe the keepout area around holes were determined by the external pad sizes, which meant there were large voids under pads on internal layers. I think the pad stack was required to give internal layers different keepouts, especially when there’s no connection on a layer next to a hole. If that is the case, pad stacks are really needed.

Top and bottom variations are my biggest need, but on the multilayer, need to have full control, as while I might have the top layer with big pad, and the bottom layer minimal pad, the inner layers in this case need to be defined. How are unconnected inner layer pads removed in Kicad at Gerber time ?
I could not see the option in Board_fabrication - gerbers - Plot.

I note there is this post:

with this suggestion : PCB Editor / Tools / Remove Unused Pads
This is good so that you can pour more copper, but then the vias stacks get out of sync with the objects.
-But in most cases I want it to happen at Gerber time, not during the design.
Most software can remove unconnected pads on inner layers at Gerber export
In Altium, default is not plot unconnected pads
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and also for removing pad shapes during PCB work :
Just like teardrops, you can go forward - backward
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Kicad is good here
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