Help with Parts with both SMD Pads and THT Pins

1

I found this post: New Part THT & SMD problem but I fear I’m “missing the woods for the trees” here!

From what I understand THT pins go on both Copper0 and Copper1, SMD Pads go on Copper1

ScreenShot-25-08-2022-01.38.41
(Ignore Layer 2 - not in use and deleted from saved svg)

My .fzp has Copper0, Copper1 & Silkscreen set.

My pads are set as

ScreenShot-25-08-2022-01.41.16

Pins as

ScreenShot-25-08-2022-01.41.07

My problem is that the THT pins DO seem to be working as expected, but my pads do not. When the part is on TOP layer, all pads and pins can be connected to from the top as expected. When I move my part to the BOTTOM layer, the THT pins are still connectable no matter what layer I’m on - to be expected. BUT, the SMD Pads are only accessible from the TOP despite my part being on the BOTTOM layer (So the Pads should ONLY be connectable on the BOTTOM layer)

ScreenShot-25-08-2022-01.40.49

So basically, the SMD PADS can only be connected to on the TOP layer - which is obviously wrong when my part is on BOTTOM layer.

What am I doing wrong?

2

The question is what is in the .fzp file? If it has both copper0 and copper1 defined in the layerId the part is through hole (and will break if used as SMD.) That is the most likely problem here.

tht part in the .fzp file:

<pcbView>
  <layers image="pcb/fc-51_85d98481ce3be6f2e9b641181c0f798b_1_pcb.svg">
    <layer layerId="silkscreen"/>
    <layer layerId="copper0"/>
    <layer layerId="copper1"/>
  </layers>

SMD part

<pcbView>
  <layers image="pcb/fc-51_85d98481ce3be6f2e9b641181c0f798b_1_pcb.svg">
    <layer layerId="silkscreen"/>
    <layer layerId="copper1"/>
  </layers>

as noted having both copper0 and copper1 defined here will make the part through hole even if you only have copper1 on the connectors.

Peter

3

Ahhhhhhh… that’ll be where I went wrong then. That begs the question though - how can I have through hole pins AND smd pads on the same part?

4

You can’t. It has to be one or the other both won’t work (it confuses Fritzing internally I believe.)

Peter

5

:man_facepalming: well damn. That’s might annoying.

I just checked out Mini USB part, which has both pads and through-holes. I see it has the same behaviour as my part - makes sense. Next question then - how do I make the smd pads active on BOTTOM layer rather than the top? is that possible? I’m guessing not?

Is copper0 top or bottom?
Is copper1 top or bottom?
(I don’t want to assume one way or the other)

6

Unfortunately there are incorrect parts even in core parts. I intend on doing a clean up at some point but it is a long term project (with lots of problems!)

It is indeed not possible as far as I know. Setting the pad to copper0 doesn’t work, as it loads the part on the top of the board by default (and although I didn’t check, probably doesn’t connect correct correctly either. The only thing I know will work is setting pcb to bottom layer only. That will by default load the part (configured with only copper1) on the bottom of the board (which I think is wrong, but the developers don’t agree.)

Peter

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