Basic question in symbol creation

Hello everyone, I have a basic question: Why can’t I specify a 3D model when creating the symbol?

Or is it possible that I’ve overlooked something?
It would now be easier for me to reuse the corresponding component in other projects.

Das 3D-Modell ist Teil des Footprints und nicht des Schemasymbols. Darum bin ich verwirrt was genau dein Ziel ist.

The 3D model is part of the Footprint not of the Symbol. This is why i am confused about what you actually want to do.

Ok, I got that, but if I use the symbol in another project now, I have to reassign the 3D model first. And that over and over again.

Warum willst du überhaupt das 3D-Model im Symbol hinterlegen? Also eigentlich müsste es doch so verknüpft sein: Symbol → Footprint → 3D-Modell.
Davon abgesehen müsstest du ein beliebiges Feld im Symbol hinterlegen können mit beliebigen Text. Dieser sollte nach einfügen des Symboles in dem Schema sein. Änderst du diesen oder fügst ein Feld hinzu kannst du dieses über Werkzeuge → Symbole aus Bibliothek erneuern auf alle Symbole im Schema anwenden.

Why do you want to store the 3D model in the symbol at all? So actually it should be this order: symbol → Footprint → 3D model.
Apart from that, you would have to be able to store any field in the symbol with any text. This should be in the scheme after inserting the symbol. If you change this or add a field, you can use it via tools → Renewal symbols from library to all symbols in the scheme.

Ok, I got that, but if I use the symbol in another project now, I have to reassign the 3D model first. And that over and over again.

workflow (creates a fully defined symbol):

  1. assign a footprint to that symbol in the symbol-editor (so it’s saved in the symbol-library)
  2. assign a 3D-model to that used footprint in the footprint-editor (so it’s saved in the footprint-library)
  3. use the symbol from the symbol-library. Every time you add that symbol the footprint is already assigned and with that also the 3D-model is already assigned.

I got it now the way mf_ibfeew described it.

Johannes auch Dir Danke.

Using one of many different examples to explain: A Polarized (electrolytic) Capacitor.

There is 1 symbol for a Polarized capacitor, but there are dozens of footprints for the different values for polarized capacitors. Each footprint needs a different 3D image, because each is a different size or has a different method of attachment to a PCB.

It is not possible to assign 100 3D images to 1 symbol, but it is possible to assign 100 images to 100 different footprints.

So, to standardize the method for assigning footprints and 3d images across the all the Kicad Libraries, the system @mf_ibfeew describes is used.

1 Like

It doesn’t really work for me, I just used the symbol in another project. The result is not the jumper!
The result should look like the image above!
There are always isolated symbols where I would define the 3D model, such as an ESP01s or D1mini or just the reset jumper. What does it change in the symbol if I put a name of a company or something similar there or just the 3D model?

What does it change in the symbol if I put a name of a company or something similar there or just the 3D model?

But you are asking for a workflow which is not supported by kicad.
The used data-model (kicad internal):

  • symbol: contains link to footprint
  • footprint: contains link to 3D model
  • 3D-model: itself

Kicad is working with and built around this data model. All expectations on the software should keep this internal data model in mind.
It seems you are looking for a shortcut symbol–>3D model, but thats not available (and in my opinion also not useful)

1 Like

You haven’t grasped the basic logic of symbols and footprints yet, and how KiCad handles them.

Symbols are symbolic representations of something. That something may be a strictly defined part, like part order # A30o8934 from manufacturer Blubby. Or it may be whatever part fullfills certain electric characteristics, like any 100k resistor.

KiCad allows different kinds of workflows with symbols. You can define a part fully with a symbol using exact identification data in the symbol fields, or you can add a symbol to a schematic even it doesn’t have any pointer to any kind of physical part at all. However, KiCad doesn’t handle the 3D model with the symbol.

The critical part of this in your workflow is that the 3D model isn’t attached to a symbol at all. You attach a footprint to a symbol. And you attach a 3D model to a footprint. Therefore, if you want two different physical parts which look different, you have a couple of options.

You can define the symbol so that it points to a footprint which includes one 3D model, and then define another symbol that it points to a different footprint which includes another 3D model.

Or you can define one symbol so that it points to a footprints which has two or more alternative 3D models, use that symbol for different purposes and modify the footprint 3D pointers in the PCB layout design (not in the schematic).

KiCad doesn’t let you define the 3D model in the symbol/schematic so that it would automatically change the model in the PCB.

Notice that nowadays KiCad allows having several 3D models in one footprint, and you can activate and deactivate them in the footprint Properties when you open the Properties in the PCB editor. That way you can have only one library footprint but modify the instance on the board without changing the library.

1 Like

If you want your symbol to represent exact element (as all my symbols do) than you with no hurt can specify exact footprint having exact 3D model linked to that footprint and you are done.
Set yourself in the position of KiCad developers and answer the question: What for symbols should have 3D model link? If the answer is ‘for nothing’ then why to lose time during program working to process unneeded information.
I have no idea what for symbol could need 3D model. May be you have got one that nobody else got.
You can add to symbol a field with specifying exact element from exact company. It seems you think it is the same kind of information as 3D model and you think: “As this one is included than why not 3D model?” But it isn’t the same kind of information. When you generate BOM exact manufacturer symbol of element can be useful but 3D models are not needed to order elements.

This topic was automatically closed 90 days after the last reply. New replies are no longer allowed.