Creating a hollow SMD pad

[mondalaci]

Hi guys,

I want to create a hollow SMD pad. In the footprint editor, I can create the inner and outer pad contours as polygons, but I can’t make a pad of them:

Thanks in advance!

[BobZ]

I see no other responses, and I do not know what you mean by a “hollow pad.”? Maybe nobody else does either…

Do you want a through hole pad which is plated? Or one which is not plated?

[retiredfeline]

I think OP wants an annular pad.

[BobZ]

Basically a plated copper donut without a drilled hole?

[mondalaci]

I want an SMD pad of the outer red contour with a non-plated through hole in the center. I only need the SMD pad on one side of the board.

I wanted to implement the above with an NPTH and a chamfered donut-shaped SMD pad around the hole.

[Dmitri_Ivanovich_Shi]

What’s the size? Most manufacturers will have a minimum distance requirement for npth to copper separation. When you say chamfered, what’s the edge you are referring to? Do you want your npth to be countersunk?

[mondalaci]

The outside diameter of the chamfered circle pad is 10 mm.

I’m aware of the required 0.2 mm NPTH-to-copper clearance, and I created the inner red circle polygon accordingly.

The chamfered edge of the circle is highlighted in green:

The NPTH is not countersunk.

[mf_ibfeew]

• you need to use the “Edit Pad as graphic shape” function to create a custom shape pad
• for this the custom shapes must be filled
• for this you have to use polygones with one contionous closed outline (your hollow shape consists of two lines - and outer and a inner line)
• unfortunately it’s hard to draw a hollow polygone with one closed outline (this needs a trick were at one point the outer line bends into the middle, forms the inner line and then goes back to the outer line so that one continous line is created. This can be examined if you import a hollow SVG-graphic-shape)

possible solutions:

1. import your filled hollow shape from an svg-file (the svg-importer creates the cntinous line for you)
2. or draw the shape as two half shapes, so you can draw every shape with a continous outline (see picture)

• both shapes must be filled
• both shapes must touch each other (or overlap), no space between them allowed
• place a smd-pad as anchor for this “custom pad” into these filled shapes
• select these SMD-pad → CTRL-E for “pad Edit Mode”, than a second time CTRL-E to end pad-edit mode
• now the pad and all connected copper-shapes are connected to one custom pad shape

[maui]

you may consider to use a mechanical sw to create such a hollow pad footprint…
an option is FreeCAd and kicadStepUp:

[scandey]

This was also discussed in an earlier thread. I also defaulted to making two closed arcs, but it turns out KiCad has a custom primitive of a “donut” or “ring” shape.

See the post below:

Help making challenging footprint with disconnected pads

[bitmap]

[mondalaci]

Thanks so much, guys! I’ve followed @maui’s solution (without using FreeCAD, by simply creating shapes in KiCad), and it worked perfectly.