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My PCB layout program of choice - Kicad - has footprints for normal rounded solder jumpers; but also triangular ones.

Examples of solder jumper pads

What benefits, if any, do the triangular ones offer? Or is it a purely aesthetic choice? Seems to me that the triangular ones would be more annoying; that they would be more difficult to clear of solder.

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  • \$\begingroup\$ In the realm of aesthetics, it looks like Adafruit (and maybe others?) use normal to indicate default closed and triangular to indicate default open. youtube.com/watch?v=uOp_2-7_1Hw \$\endgroup\$
    – Johannes Hoff
    Commented Jul 2, 2022 at 14:58
  • \$\begingroup\$ Wouldn't default-closed pads already be obvious? You can see that they're closed. \$\endgroup\$
    – Sod Almighty
    Commented Jul 3, 2022 at 15:55
  • \$\begingroup\$ When you first get the PCB, yes, but after changing it might be harder to spot how it used to be. No idea how useful it is in practice. \$\endgroup\$
    – Johannes Hoff
    Commented Jul 5, 2022 at 8:31

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For the same height of pad, the angled ones provide a higher length of the gap, meaning simply that there's a higher chance to find a random spot where the solder creates an initial bridge, before surface tensions "pulls" the solder to connect across almost the full height.

Also, but this is more speculation than the previous sentence, the concave part might lead to a solder blob is centered at the "dent", minimizing the gap distance, further increasing likelihood of a successful solder bridging.

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  • \$\begingroup\$ And by that same token, be even more of a bastard to get the solder back off again? \$\endgroup\$
    – Sod Almighty
    Commented May 19, 2019 at 18:47
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    \$\begingroup\$ Yes, it's a trade-off between ease of closing and ease of opening. Typically in a production setting, nobody would be repeatedly closing and opening the jumper - it would come out of the SMT line with the jumper open, and if it needs to be closed to configure the board then that only has to happen once per jumper, and it'll be staying that way. That said - with solder wick (aka desoldering braid) it's quite easy to open this style of jumper. \$\endgroup\$
    – pericynthion
    Commented May 19, 2019 at 19:13
  • \$\begingroup\$ @SodAlmighty removing solder is generally much easier then creating a solder bridge. All you need is a bit of solder wick and possibly a bit of flux. (and of course a solder iron) \$\endgroup\$
    – Rene Pöschl
    Commented May 22, 2019 at 16:49

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