Adding Paste and Mask to Footprint with Thermal Pad and Vias

I’m trying to use footprint files (originally downloaded from TI and converted to KiCad by Ultra-Librarian tool). The parts have thermal pad and thermal vias. Somehow the conversion tool generated footprints that caused DRC issues which I fixed based on hints found on this forum.

There is one issue which I’m still confused about, which is:

Q. How to properly place Paste (stencil) and Mask entries for the thermal pad and vias in KiCAD in order to adhere to the recommendations in the following document: PowerPAD™ Thermally Enhanced Package. - i.e., avoid issues like wicks and voids listed in sections 2.4 and 2.5.

Specifically, in the following example the entries for Paste and Mask of Pad 11 seem to be very small: (pad “” smd rect (at 0 0) (size 0.0254 0.0254) (layers F.Paste F.Mask))

Here’s sample footprint file (Sorry, I was not permitted to upload kiCad_mod file as a new user):

(module TPS26624DRCR (layer F.Cu) (tedit 0)
(fp_text reference REF** (at 0 0) (layer F.SilkS)
(effects (font (size 1 1) (thickness 0.15)))
)
(fp_text value DRC0010J (at 0 0) (layer F.SilkS)
(effects (font (size 1 1) (thickness 0.15)))
)
(fp_circle (center -1.000001 1.000001) (end -0.700001 1.000001) (layer Dwgs.User) (width 0.1524))
(fp_line (start -1.625001 -1.625001) (end -1.000001 -1.625001) (layer F.SilkS) (width 0.1524))
(fp_line (start -1.625001 -1.4) (end -1.625001 -1.625001) (layer F.SilkS) (width 0.1524))
(fp_line (start 1.625001 1.625001) (end 1.625001 1.45) (layer F.SilkS) (width 0.1524))
(fp_line (start 1.45 1.625001) (end 1.625001 1.625001) (layer F.SilkS) (width 0.1524))
(fp_line (start 1.625001 -1.45) (end 1.625001 -1.625001) (layer F.SilkS) (width 0.1524))
(fp_line (start 1.45 -1.625001) (end 1.625001 -1.625001) (layer F.SilkS) (width 0.1524))
(fp_line (start -1.625001 1.625001) (end -1.625001 1.45) (layer F.SilkS) (width 0.1524))
(fp_line (start -1.625001 1.625001) (end -1.45 1.625001) (layer F.SilkS) (width 0.1524))
(fp_line (start -1.525001 -1.525001) (end 1.525001 -1.525001) (layer Dwgs.User) (width 0.1524))
(fp_line (start 1.525001 1.525001) (end 1.525001 -1.525001) (layer Dwgs.User) (width 0.1524))
(fp_line (start -1.525001 1.525001) (end -1.525001 -1.525001) (layer Dwgs.User) (width 0.1524))
(fp_line (start -1.525001 1.525001) (end 1.525001 1.525001) (layer Dwgs.User) (width 0.1524))
(fp_text user “Copyright 2016 Accelerated Designs. All rights reserved.” (at 0 0) (layer Cmts.User)
(effects (font (size 0.127 0.127) (thickness 0.002)))
)
(pad 11 thru_hole circle (at 0.575 0) (size 0.499999 0.499999) (drill 0.2032) (layers *.Cu *.Mask F.SilkS))
(pad 11 thru_hole circle (at -0.575 0) (size 0.499999 0.499999) (drill 0.2032) (layers *.Cu *.Mask F.SilkS))
(pad 11 thru_hole circle (at 0 -0.950001) (size 0.499999 0.499999) (drill 0.2032) (layers *.Cu *.Mask F.SilkS))
(pad 11 thru_hole circle (at 0 0.950001) (size 0.499999 0.499999) (drill 0.2032) (layers *.Cu *.Mask F.SilkS))
(pad “” smd rect (at 0 0) (size 0.0254 0.0254) (layers F.Paste F.Mask))
(pad 11 smd rect (at 0 0) (size 1.649999 2.4) (layers F.Cu))
(pad “” smd rect (at 1.4 -1.000001) (size 0.600001 0.249999) (layers F.Paste))
(pad “” smd rect (at 1.4 -1.000001) (size 0.600001 0.249999) (layers F.Mask))
(pad 10 smd rect (at 1.4 -1.000001) (size 0.700001 0.349999) (layers F.Cu))
(pad “” smd rect (at 1.4 -0.499999) (size 0.600001 0.249999) (layers F.Paste))
(pad “” smd rect (at 1.4 -0.499999) (size 0.600001 0.249999) (layers F.Mask))
(pad 9 smd rect (at 1.4 -0.499999) (size 0.700001 0.349999) (layers F.Cu))
(pad “” smd rect (at 1.4 0) (size 0.600001 0.249999) (layers F.Paste))
(pad “” smd rect (at 1.4 0) (size 0.600001 0.249999) (layers F.Mask))
(pad 8 smd rect (at 1.4 0) (size 0.700001 0.349999) (layers F.Cu))
(pad “” smd rect (at 1.4 0.500002) (size 0.600001 0.249999) (layers F.Paste))
(pad “” smd rect (at 1.4 0.500002) (size 0.600001 0.249999) (layers F.Mask))
(pad 7 smd rect (at 1.4 0.500002) (size 0.700001 0.349999) (layers F.Cu))
(pad “” smd rect (at 1.4 1.000001) (size 0.600001 0.249999) (layers F.Paste))
(pad “” smd rect (at 1.4 1.000001) (size 0.600001 0.249999) (layers F.Mask))
(pad 6 smd rect (at 1.4 1.000001) (size 0.700001 0.349999) (layers F.Cu))
(pad “” smd rect (at -1.4 1.000001) (size 0.600001 0.249999) (layers F.Paste))
(pad “” smd rect (at -1.4 1.000001) (size 0.600001 0.249999) (layers F.Mask))
(pad 5 smd rect (at -1.4 1.000001) (size 0.700001 0.349999) (layers F.Cu))
(pad “” smd rect (at -1.4 0.499999) (size 0.600001 0.249999) (layers F.Paste))
(pad “” smd rect (at -1.4 0.499999) (size 0.600001 0.249999) (layers F.Mask))
(pad 4 smd rect (at -1.4 0.499999) (size 0.700001 0.349999) (layers F.Cu))
(pad “” smd rect (at -1.4 0) (size 0.600001 0.249999) (layers F.Paste))
(pad “” smd rect (at -1.4 0) (size 0.600001 0.249999) (layers F.Mask))
(pad 3 smd rect (at -1.4 0) (size 0.700001 0.349999) (layers F.Cu))
(pad “” smd rect (at -1.4 -0.500002) (size 0.600001 0.249999) (layers F.Paste))
(pad “” smd rect (at -1.4 -0.500002) (size 0.600001 0.249999) (layers F.Mask))
(pad 2 smd rect (at -1.4 -0.500002) (size 0.700001 0.349999) (layers F.Cu))
(pad “” smd rect (at -1.4 -1.000001) (size 0.600001 0.249999) (layers F.Paste))
(pad “” smd rect (at -1.4 -1.000001) (size 0.600001 0.249999) (layers F.Mask))
(pad 1 smd rect (at -1.4 -1.000001) (size 0.700001 0.349999) (layers F.Cu))
)

Would greatly appreciate any help.

Might be a good read: Tutorial: How to make a footprint in KiCad 5.1.x (From scratch)?

Oh and by the way we have scripts that generate such footprints using IPC recomentations (which are listed as an alternative in ever TI document) https://github.com/pointhi/kicad-footprint-generator/tree/master/scripts/Packages

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