Solder mask for bottom side fiducials

Layout Footprints
1

I have a PCB layout with bottom side SMT components, and am wanting to put fiducials on the bottom side of the PCB for when I run this through my PnP machine.

I’ve come at it from two angles, neither of which seem to be giving me the result I want.

  1. Place the Fiducial:Fiducial_1mm_Mask3mm PCB component from the standard library and then flip it onto the bottom side. For whatever reason, the expansion of the solder mask around the pad doesn’t get flipped onto the bottom solder mask:

image
image

  1. Creating my own bottom side fiducial component, with an SMT pad on the bottom side, and all other parameters the same as the standard top side fiducial. But again, it doesn’t have the expanded soldermask around the SMT pad (which I need for reliable recognition by my Juki)

Anyone have any ideas on how I can get this to work?

Cheers,
Mike

2

In version 5 ? 6.0.2 ? 8.0.7 ?

You will help others to help you if you post a zipped Project showing the issue, and if you tell us the version you are running:

Can you paste your version info here please, you can get it from KiCad > Help > About KiCad > Copy Version Info
image

1 Like
3

As the previous answer already stated: always give enough information to the reader of your question. For all questions regarding kicad this incorporates at least the used kicad version.

My guess: You are using Kicad v9.0.0 or v9.0.1. These versions had a problem with bottom layer solder mask expansion. Therefore the advice (based on that guess): update to the most recent v9.0.2 version and your bottom side fiducial should work.

3 Likes
4

@mf_ibfeew - thanks. That appears to be the issue. I was actually on V9.0.0

Cheers,
Mike