Newbie and jumpers

Aloha !

I have been playing with KiCad for a couple of weeks and after scribbling a lot, I thought trying to make a real circuiboard which I can order from some Chinese factory. COUGH-pcbway-COUGH :wink:
Thus I started a whole new project and so far everthing work as intended (I think) except for the jumper on my tiny board.

In the schematic I have used : Jumper_3_Bridged12
When I look at the PCB it seems to be there but…

…in the 3D model there is no jumper. Only a 3 pin header.
And on top of that, the jumper is not present on the BOM :sob:

What could I be doing wrong ???

Cheeeeeeeeeers

Jecepede

Well, 'cause you’re asking for it. Your whole introduction is not relevant to your problem. You might as well have skipped the first paragraph.

That jumper does not have a default footprint.

Another thing you did wrong is not mentioning which footprint you added to that schematic symbol. If your jumper has no footprint then, during Schematic Editor / Tools / Update PCB from Schematic [F8] you will get a message like: Error: Cannot add JP1 (no footprint assigned).

That can only be true if you have assigned a footprint, for example:

Jumper:SolderJumper-3_P1.3mm_Bridged12_RoundedPad1.0x1.5mm

(I choose that one because it looks a lot like the schematic symbol).

Footprints like those jumpers are fully implemented in copper, and other standard PCB layers. Therefore they do not have a 3D model, and they also do not appear on the BOM. There simply is nothing else to add to the PCB except for the footprint itself.

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While that footprint looks really cute, there can be an issue. If you have to cut the existing copper link and the feature is small, making a clean cut in a tiny space is difficult. I would use the 3 pad footprint but WITHOUT the short. Make a longer deliberate trace for the short. Much easier to cut it. Place a X over the trace as an indication of where to cut.

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and dont put any solder mask in the gaps (IE place a pad of mask (IE no solder mask) only over the gap.)

I’m facing that issue on some production PCBAs . . . fortunately we haven’t had a need to “cut” the track on any of them so far. Thanks for the idea.

Another option is to use 0-Ohm resistors as jumpers. Placements of those does cost a bit of time / money for each board, but you can configure them during (automated) assembly.

Maybe the confusion is that OP wants to add “normal” jumper not SMD one?
Normal jumper is “just” two 2.54mm pin connector…

Yup, you may be correct . . .

In that case I would create a dummy symbol for the physical jumper so it gets into the BOM and create a footprint that just contains the 3D CAD of the jumper.

Needs a little experimenting . . . not done anything like this before on KiCad.

I’ve posted a full set of my Jumper Wires in the past here’s an example of 8mm

Symbol (create your own)
Step files - attached

Jumper-Wire_8mm_Blue.step (15.1 KB)
Jumper-Wire_12mm_Red.step (15.9 KB)
Jumper-Wire_20mm_Blue.step (142.2 KB)
Jumper-Wire_25mm_Blue.step (117.1 KB)

I would do generic 2 pin connector symbol, set the footprint to 2 pin header 2.54:

Then I would get the jumper STEP file somewhere (this one is from GrabCad) and then add it as second 3D model on the footprint:

Still need to get the Jumper into the BOM though . . .

True, true. The second symbol is a good solution then…

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Aloha !

Thank you everyone for the overwhelming answers. I have read everything with great enthusiasm…

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Uhmmm I was just trying to be nice and not someone who demands an answer. :worried:
Please honour the community guidlines : “Constructive criticism is welcome, but criticize ideas, not people.

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Nope, never got that error. It has a footprint but it is only the pin headers, there no jumper on it ?
By the way I need a real jumper. No a soldered one. For me I need to open my computer, change the jumper en close my computer. No soldering required…

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If I understand right, you are correct. A little piece of plastic that slides over the 2.54 pin connector I have on the board is all I need.

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Wait, what ? A sophisticated piece of software like KiCad 7 does ot have a simple piece of plastic in it ? That can’t be right ?

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THAT look exactly what I need. I will try this for sure. Getting it in the BOM should not be that hard afterwards… #FamousLastWords :rofl:

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Thank you again everyone for the answers.
I have been helped a lot :slight_smile:

Cheeeeeeeeers

Jecepede

I will ignore the sarcasm. But for example on the mentioned GrabCad you can find a whole pack of different jumpers (sizes, colors,…) https://grabcad.com/library/jumper-2-54mm-pitch-1

Aloha !

This worked like a charm. Look at the jumper sitting on top of the header. And added bonus, I can even choose colors. :+1:

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Sorry, it was not meant to be sarcastic only very surprised. I mean really…
Something as basic as a jumper does not exist ? To me that sounds like a chicken farm… without any eggs. Yes you can get chicken legs to eat or feathers for in pillows but no eggs :hushed:

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Cheeeeeeeeeeeeeers

Jecepede

KiCad does not have models of screws but it has “models” of mounting holes. It has models of barrel jack connector but not barrel jack plugs. It is designed to design the PCB and from that point of view jumper is just some pin headers. It is more important whether the pins are horizontal, vertical, through hole, smd, pitch, etc…

By using grabcad, snapeda, manufacturer pages, etc you can easily get models of almost anything and you can easily create your own symbols and/or footprints and finetune them to your liking.

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Aloha !

Ohhhhh now the penny has dropped with me and that makes sense now.
KiCad also does not have the box you use to mount everything in and the cupboard on which you set the box on top of. It is about the schematic, not the rest of the world.

I guess I got confused coz in the schematic it said “1-2 Bridged”…

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Cheeeeeeeeeeeers

Jecepede

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There is a SketchUp plugin to bring your PCB into FreeCAD. If that is something too much, someone on this forum suggested creating a dummy footprint with 3D model of the box (enclosure) so you can see it directly in KiCad. You can then pretty easy position it, rotate it, disable/enable it… Or you can export the PCB as STEP… You can do a lot in KiCad, but it is designed for a PCB design and some things are in form of plugins or clever usage of existing stuff :slight_smile:

That is because you selected a SMD solder jumper and that can be either open or bridged on the PCB. It is basically 2 (or more) pads that are either not connected (open) and if you want them to connect, then you need to solder them over. Or they are connected via thin trace (bridged) and then you need to cut the trace if you want them disconnected.
Here is example of two pads jumper open:


Sorry for the crappy image from a phone, I did not have my scope at hand…