Back silkscreen hidden by back copper?

I have a two-layer board created in KiCad 7.0.0. There is one SMD IC and several THT components, all mounted on the front side. All traces are on the front except for a power lead on the back. There is a ground plane on the back. I have some text on the back silkscreen that ID’s the board and the rev. level.

The back silkscreen is not visible if I have the ground plane visible. What am I doing wrong? Thanks.

If all IC’s are placed on the front side, then maybe there just is no text on the B.Silkscreen layer at all

Thanks for the reply. I created some text on back silkscreen layer to ID the board. I can see it there, but only if I turn off the visibility of the back copper layer. It’s probably something I don’t understand.

The order in which layers are drawn on-screen in KiCad is “dynamic”. The “active” layer is always on top, and silkscreen is most often drawn under most other layers. If there is a lot of copper on the PCB, then Silkscreen is most often hard to see.

You can Click on the Bl.Silkscreen layer on the Appearance Manager on the right. That will make your B.Silkscreen layer active and put it on top.

You can also right click in the appearance manager, then turn off the visibility off all layers, and then maybe B.Silkscreen visible again by clicking on the “eye” icon in front of it’s name.

Yet another way is to open the 3D viewer (With [Alt + 3] or from the menu), and then flip the board around.

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Experiment with transparency manipulation in Appearance - Objects.

Are you referring to the PCB editor view? Isn’t that what’s expected? The B.SilkS layer is the furthest back so any B.Cu would obscure it unless you turn off display of that.

In the 3D viewer you will see B.SilkS when you turn the board around. Good enough?

I don’t think so.
During PCB design there is no arguments to see it as true PCB but you should see it in the way that helps you design it.
I think the relation between F.Silk and F.Cu should be the same as between B.Silk and B.Cu.
In past (before KiCad) I had many projects with all elements at bottom. I will do their next versions with KiCad and I hope working at bottom is the same as working at top (without flipping the whole PCB).
I did it to see PCB from the side the user will see the device to have the true view of all user interface elements positioning.
I don’t see the reason to have a work on such PCB being more difficult than to work where you place elements at top. So if the order of F layers were selected to be the best for working than order of B layers should be the same (even you are looking at PCB from top).
Thinking that during designing PCB you should have layers in the order as they are in real PCB is unjustified in my opinion. The PCB body hides all bottom layers so you should not see them all?

That’s a non-argument. There’s nothing to be gained by seeing the PCB body, you know it’s there. You don’t need to invoke this to argue for a different visibility order.

Let’s imaging a different scenario. The designer has fine tracks on B.Cu and has put a big whopping company logo in yellow on B.SilkS. Does showing B.SilkS in front of B.Cu make sense here? One order will not suit everybody. Now we have visibility and opacity control. Are there layer order controls too? I haven’t looked that deep. If not should there be?

Flip the board and read with a mirror? :slightly_smiling_face:

This was only to emphasize that thinking about the actual layer order when determining the visibility order is in my opinion unfounded.
Silk layer is typically much less filled than copper layer. If Silk is seen before copper it disturb the view of copper much less then if they are opposite. For me the conclusions are obvious.

You added it after I have written my previous sentence. In that case you are right. But don’t you see the same problem if he add that logo at F.Silk. Here the right question is: for 1000 PCBs designed all over the world at how many of them there is big logo at B.Silk? And if it is, isn’t it placed as a last design step searching the place where vias not disturb?

Or write a wish in bug report system with good arguments for.
When I will come to designing such PCB with KiCad and find problems I don’t have designing at top than may be I will do it.

You are putting yourself in a unenviable position because there only needs to be one counterexample to your argument. But I’m not interested in looking for it. But maybe after years of use nobody puts in a request to be able to reorder the layer display bearing in mind that the GUI controls will be complicated, probably some kind of drag and drop of layers, then we’ll just have to live with flicking visibility and tweaking opacity. Which I think is no big deal.

Addendum: I did a little exploration. I don’t see any GUI controls to reorder layers in the PCB editor. But besides the visibility and opacity controls, there are presets which could be useful for quick switching. The other observation is that gerbview orders the layers as you would expect.

gerbview

I don’t understand it.
One example when silk disturbs working with cu would be enough only if cu disturbing the work with silk would be impossible. But it become not important as everything changed when I could see KiCad running.
What was my main thesis was that layers should be in order that much helps design. So the same order that is found to be good for front layers should be also good for bottom layers and it should define layers order and not their real order at PCB when looking at it from front. It is why I protested when you said that expected order at KiCad is based on fact that B.SilkS i furthest back than B.Cu.

Previous posts I was writing without looking at KiCad working.
Now I can run KiCad and I see that F.Cu is in front of F.Silk (when you click F.Silk to be in front than any graphic layer then F.Silk is hidden by F.Cu). So based on it I will say that B.Cu should be in front of B.Silk (as they are) not because they are in that order when looking at PCB from front but such order was assumed to be better for working for front layers so it is also better for bottom layers.
So going back to your first argument:

How is it applied to F.SilkS and F.Cu?

You spend much more time working with cu than with silk and I think it is the reason why F.Cu is in front of F.Silk.

Hmm, strange. My project last worked on in v6 opened with F.SilkS on top, then it went under F.Cu after some clicking. Anyway, there are times I want to read the silkscreen so I would control the visibility or opacity. I wouldn’t trust the built-in order whichever that is, I would want to see the layer clearly.

Addendum: This is how it looks when I first open the board. I know which click made the Cu come on top, but I can’t explain it and it’s of no import to me so I’ll leave it here.

silk-over-cu

Addendum: That screenshot has also shown me that somehow KiCad has reverted to the old v5 scheme. I thought I had fixed KiCad to use the KiCad default but it’s picked it up again. Anyway I got rid of it by clearing out the user settings for color in the config directory.

For 30 years we didn’t used silk at our PCBs. We used silk layers to generate our documentation. When I moved to KiCad I decided to use Courtyard layers for documentation so I got silk layers to be used at PCB. I have there only rectangles around footprints and text identifying PCB.

Yeah silkscreen is a luxury. No such thing for us hobbyists when I started with single sided phenolic boards and FeCl3.

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To get FeCl3 was a problem. Fortunately my uncle worked in a chemical plant (at the other end of the country). In those days, without telephones, everything had to be arranged by letter.

Just so I am not misunderstood, I am not complaining about KiCad, nor am I asking for a change. I just didn’t understand how to use the controls. The program I came from always placed layers in the order in which they physically were on the PCB. For example, in a two-layer PCB, they were in this order.

Top Silk
Top Mask
Top Copper
Bottom Copper
Bottom Mask
Bottom Silk

And there was the option to view the board from the top or from the bottom. So, I became accustomed to look at the board from the bottom and seeing the bottom silk on the top in that view.

KiCad has many more options, and I was getting lost in them. Now, I think I understand that topic well enough that I won’t have this problem again.

Of course, there will always “something else” that baffles me.

Thanks for your patience and the help you all try to provide.

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