Flipping "dual-side" component?

Just to start off, I’m not talking about flipping a component to the front/back side of the PCB. I’m using right-angle (horizontal) SMD LEDs like this QT Brightek QBLP615-IW-CW:

As you can see, it can be mounted on either side so the lens faces either direction. But there doesn’t seem to be a way to flip/mirror a component’s footprint in pcbnew so that I have it face a different way. Technically, the footprint is symmetrical so it won’t physically matter, but it won’t work when trying to wire things up in pcbnew.

I got around this simple enough by just duplicating the footprint and swapping the pads. So I could use this “flipped” version of the footprint when I wanted the LED to face the other direction. But I was wondering if there’s another way to do this that I’m missing?

Some components can be used upside down if handled manually, but assembly factories hardly do that. So there’s not much need for that feature, especially when footprints can be rotated, and even the recommended footprint for this part seems to be asymmetric. KiCad doesn’t have that kind of functionality.

Does not compute.
(Behind this keyboard)

You can flip a component to the other side of the board with f,and you can also rotate a footprint with r (Usually in 45 degree increments).

Usually there is also some marking on the silk screen which help to prevent from mounting diodes (so also LED’s) backwards.

You always have to be carefull with leds. Some are marked at the Anode, others are marked on the Cathode, and those can be from the same manufacturer and the same housing.
So, from your picture there is no telling whether the green stripe is on the Anode or Cathode side.
Is this what you wan to say? You have a Footprint for which the Anode is marked, and a physical LED for which the Cathode is marked?

Another way of interpreting is you are aiming at “reverse mounted LED’s”.
These are designed for mounting over a hole in the PCB, and then shine their light though that hole.
Therefore, they’re also put in the tape “upside down”.

The led you’re showing looks a lot like the “side view LED” mentioned in:

Yea, it’s a unusual situation so I understand the confusion. I know this is a side-view LED, and it is on the back of my PCB. So I used f to to it on the back and then r to rotate it how I want it. My issue is that in this configuration the cathode pin is always on the same side (towards the inside of the board), but I want it to be on the other side (facing toward the outside of the board). This is easy to handle when soldering because the LED in symmetric (across the y-axis), so I can just physically flip it and solder it. So basically, I just want to swap the pins on the layout.

I think I’ve actually found a plug-in that does this, but I haven’t tried it yet.

I plan on hand soldering (small batch for a personal project), so no problem with manufacturing. Technically rotating would work, but there’s a nice outline and markers on the silkscreen and fab layers in the LED’s footprint that would not make any sense then.

I basically just need to swap the pins on the footprint, which I did by duplicating the footprint and manually changing the pins in the alternate version. I was just wondering if there was an easier way to do this, but it doesn’t seem so. Although, I think I found a plug-in that does it but I haven’t had a chance to try it yet.

That’s right. It seems I understood your use case correctly. My previous post gives reasons why there’s no ready-made function for it in KiCad. I have used some similar LEDs myself and can see how it would be useful to turn it upside down, but it’s just not common enough need to warrant a software feature.

In my opinion it is good that there is no way to mirror element.

  1. If such diodes are packed laying in tape once on one side and once on the other side then they have to be ordered specifically - so they should have different symbol in BOM so starting from schematic symbol there should be difference and no problem to add separate footprint to those symbols.
  2. Possibility of mirroring can give you unnoticed errors. Many years ago someone learning PCB design (not electronic) was asked to have the next 4 circuits being symmetrical (in sense of terminal block pins) to the first 4. It was in Protel 3 where you can swap footprint against X or Y axis by pressing X or Y key. I didn’t noticed how it was done and we had a serie of PCBs we had to mount SOT23 transistors on their backs.

Ah, good point regarding how the parts are packed in tape. Didn’t think about that. Yea,that would definitely not work with manufacturing.

Ok, cool. So my hacky way of duplicating the footprint and swapping pins seems to actually be the “best” solution for my case. Just wanted to make sure there wasn’t an easier way I was missing.

Thanks everyone!

Taking Footprints from KiCad’s default libraries and modifying copies of them is a very normal procedure indeed.

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