Silk and reference in layout

Hello!

I’m going to assemble a PCB prototype, and usually what I need is something like this:

  • Leave silk as it is;
  • Write the value inside of the component’s outline.

However, it seems that the value and a copy of the reference label are in the same F.fab layer. So if I remove the reference that I don’t need because it’s usually the same as the silk, I will remove also the value.

Is there a way to get rid of the reference, or put it in another layer?

Thanks!

Can you go into the footprint properties and tick or un-tick the ‘show’ column or change layers in the layer column?

Hello!

Thanks for your reply.
As for the “show” checkbox, I tried (also before your reply, and I double checked). It doesn’t change anything, it’s still there.
As for the layer change, that’s indeed a good idea and it works, but in this case, I have to change in all my components. Is there a way to do that quickly? Maybe changing the ref in the library and update the library?

By the way, in the footprint editor, there are many user layers. I can’t move it in any other layer except maybe User.eco, but on the other hand I don’t know what it means. Is it possible to rename a layer? For example F.ref and B.ref would be fine. I tried righ-clicking the user.x layers, but there is no rename in the menu.

Sorry, don’t know. I’m still using 5.1.9. Stuff has probably changed in your version.

Tonight I’m going to take the plunge and install 5.99…hopefully :roll_eyes:

My solution was:
Before start first PCB with KiCad I analysed how I wont it be organised and all my footprints I have defined according to my needs. I never searched how to modify it at PCB level.

Hello!

That’s certainly a better solution as long as you’re aware that there is a reference in the same layer as the value. I didn’t know that, and I didn’t even notice because I disable F.fab to do the routing.

That said, having the reference and the silk in 2 different layers makes sense. Example, you can determine the behavior of one program, for instance 0 is ARGB555, 1 is RGB565, in which case you can have the reference which is for instance R1, R2, and the silk ARGB1555 for R1 and RGB565 for R2.

I’m not quite sure what you are trying to accomplish.
Silkscreen is intended to be printed in white on the PCB.
F.fab is meant (as I understand it) to be printed out on paper for your reference (eg. during assembly).
Which one do you mean and how do you intend to use it?

Edit -> Text and Graphic Properties. As far as I could understand this is what you want:

Hello!

What I’m trying to do is to obtain an implementation map. Usually what I need is:

  • Slik (shows the component outline and the referebce (R1, R2, etc…)

Oops, I sent it too early

  • Value (inside of the component), so I can implement it myself, playing several instruments (soldering iron, etc…) with the map on a music score holder.

Here is how it looks (inverted, I print black on white). And the value is in the r / c code way. 104 is 100 nF.

Screenshot from 2021-03-16 18-43-34

And my problem is that there is already a reference like this:

Screenshot from 2021-03-16 18-46-22

And if I disable the F.fab layer, I get this:

Screenshot from 2021-03-16 18-46-40

So I’m looking for a way to get the silk and the F.fab without the reference, as shown above,
but which would be done automatically.

Thanks

Please note, putting silk under components is not really advised… Depending on what type of polymer ink is used (and by whom) it may sit quite proud with regards to the paste so when the card is reflowed (eg cap, resistors), they don’t really make contact.

Sometime it is ok, sometimes it is not…

Hello!

It’s not silk under the component, but the F.fab layer. It was the same color because I have edited manually for explanation, and it was selected. You can notice in the second picture that it’s grayish.

Did you try Edit -> Text and Graphic Properties, shown in my previous post? You can of course change the settings to get what you want.

The clean solution would be as follows:

Keep the silk layer for only silk. Set it up to work with production. I guess you want to also have the value on this layer so duplicate the value on this layer (similar to how the reference is already duplicated to this layer in the assets of the default lib)


Then when you print your reference sheet to be put on the music stand then print ONLY the fab layer. Set that layer up to have what you need on it (the outline, reference and value should already be there on this layer if you use the default libs)


By the way this is a difference between kicad and eagle. In eagle there is a “layer” for values and references as well as two where outlines go (differing level of detail on each layer), Then when making the gerber for silk or when exporting for printing one selects which combination of layers one wants.

In kicad you typically use one layer and duplicate the elements you need on multiple layers. (This way you can then even have things like different text sizes for silk vs printout or also different positions like having something under the part for printouts but not for silk)

I find what you write a bit confusing. You write “silk” but you don’t seem to mean the silkscreen print on the PCB?
As I understand it, you want a paper printout for manual assembly, in the style you showed above (value inside and reference outside component. Correct?
Do you care about the silkscreen print on the PCB or how do you want to handle that?

I Assume MartinS wanted to reply to roboya, not to me.

I agree with others here: Silk is for printing on the board, and it should be readable when the board has been assembled and no other documentation exists.

Fab layers are for documentation and helping assembly. That’s why the Value and Reference are both in the Fab layer, along with the full component outline, in the KiCad libraries. I have used printed Fab layer for manual assembly.

For documentation you need a layer pair - when you flip footprint picture goes to another layer of pair.
I have a battle with it since 3 years.
Silk - not, because it is to be printed at PCB - it is different than in documentation,
CrtYd - not, because DRC checks it and if you add some polarity marking DRC screams on you,
Fab - not, because real dimensioned elements (0603, 0402) are to small to place readable text inside.
So for me none of that layers pair is good for documentation, and you don’t have extra pair to be used for it. I considered even using Adhes layers for documentation needs as I don’t use adhesives, but you can’t be sure if you will not need to use it in future so better not.
Last half year I used Fab for documentation (with normal Fab pictures moved to Eco2).
I spend whole yesterday reverting all my footprints back to my previous solution - to use CrtYd for documentation because I found that I need Eco2 to other (new for me) purpose.

Your previous post was quite confusing, especially without this comment you added later:

Without that comment the pictures do not have a meaning at best, and are misleading at worst.

In that previous post both the big “104” and the “C23” disappear if you turn off the Fab layer. which means that both texts are placed on that Fab layer you turned off.

It is of course very easily fixable:

  1. Turn on the Fab layer so you see the text.
  2. Click on the “104” text to highlight it.
  3. Press e for edit, and move it to the F.SilkS layer.

Doing this for each of your resistors separately is a bore, but there is an solution for this too.

  1. Create a custom Footprint library for this project.
  2. Copy one of the standard resistors to it.
  3. Modify it to your liking and save it.
  4. Eeschema / Tools / Edit Symbol Library References
  5. Update all your resistors to use the newly created custom footprint.
  6. Eeschema / Tools / Update Pcb from Schematic [F8]
  7. Make sure you have: "Options: Update footprints turned on.

As you use KiCad more, you will make more personalized schematic symbols and Footprints and organize them in your personal libraries and do just like Piotr: Have a personal style and do it right the first time :slight_smile:

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