How to draw this kind of copper area?

Hi

I have posted a wishlist in launchpad (albeit a workaround until v6) asking for the ability of importing a graphic into a copper layer for exactly this reason. My logic being that you could create your layout in a CAD prog, Inkspace, inventor whatever, which included your CapSense pads, traces, the keep-out zones around the pads, GND Hatching etc and just dump it piecemeal onto copper layer. It would require no ‘intelligence’ from KiCad nothing new needs to be programmed for this functionality other than ‘un-hide’ the copper layers from a drop down list.

At present you have the ability to import a graphic onto any non copper layer. There is no copper layer available in the import dialogue box.To me this is ridiculous!

Regards
Matt

I am not sure graphic import is the best option for all of your sub usecases. particularly for ground hatching there are better options already in current nightly builds.

Most of the rest can be already achieved using freecad and the stepup plugin. Or even svg2shenzen.

Unfortunately importing graphics to copper layers will probably not be backported to the 5.1 series since it is a major feature. In general only bug fixes and associated changes are backported.

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Why?

Would it not be easier and nicer user experience just to allow us to import onto a copper layer anyway if we wanted to, whats the problem? The fact that someone has sat down and written code (svg2shenzen) proves the fact. Are KiCad developers worried that we, the users, might create a penis or a pair of big boobs permanently etched in copper with miniature flashing LEDs outlined with a white silkscreen on the next iteration of a knock off copy of an Arduino nano? I don’t think so!!!

Look, all I’m saying is, I have been messing around with Inkscape and svg2shenzen for over two days now. I created my desired graphic in under 15minutes but I just cant get it into Kicad! aaarrgghhh!

svg2shenzen and by association Inkscape is an overkill and a pain to learn. I know illustrator, Photoshop, Acad, Fusion, Corel. You now expect me now to learn another package just to import a graphic into a copper layer. All the packages I’ve just mentioned have the capability to create my required CapSense design MUCH more simply than KiCad - (5x20mm pads on 2.54mm centres with hatching covering 100x50mm). Remember Capacitive Touch sensors come in a variety of shapes styles - wheels, sliders, chevrons etc, How is future KiCad going to deal with these? None of the existing polygon tools will allow us to ‘draw’ onto copper layers. So you are implying that KiCad is and will be incompatible with modern touch interfaces?

So, if I want anything other than a pad in copper, KiCads ‘people’ expects me to learn another piece of software and workflow. Kicad already has mechanisms, core functionality, in-place to draw shapes, fill shapes, import graphics and have them implemented correctly on an appropriately layer but just not on copper - like I said it is a ridiculous.

Automated hatched copper pours is a massive coding change and probably a lot of work, making a check box visible isn’t which is the point I’m making.

The kicad release policy. Everything you wish for (including copper hatch fill) is already in nightly as already explained to you in multiple responses above (and will therefore be in the next release expected to happen in about two years time)

The solutions i gave are however possible to use with the current stable releases.
The stepup option will (as long as it is maintained) always be more powerful than anything available within kicad as it can directly use the powerful tools of a proper parametric cad program.

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I would hardly call it a “major feature”. Just adding more layers to a to a drop-down list. Graphics can already moved from any layer to a copper layer, but only one item at a time. There exists a plugin which can move several items at a time (see How to move several graphic lines from one layer to another?). I would say this is the easiest way to get graphics into copper at the moment.

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Rene, I am making a point that a potential quick fix as a stop gap is a viable option instead of waiting for approx. 2 years for the ‘official’ full functional workflow. This fix would also pave the way for increased productivity in light of ‘new’ technology (Cap. Touch).

I do object to your tone asserting that you keep telling me things and I’m not listening! I am not ‘not listening’ I am disagreeing with the logic of having to use a nightly build or learn new software instead of the developer just making copper layers visible during the import command.

As documented in Launchpad, there are 2 planned updates before v6. I accept that no change will happen in time for 5.1.5 but that still leaves 5.1.6 doesn’t it or even a 5.1.7, 5.1.8, 5.1.x

Look, someone in development cycle has made a decision NOT to include copper layers in the import dialogue menu, this can easily be reversed as the underlining function has to be in place for all the other layers to be available.That’s all I’m saying

The example given obviously is no flex board.
So what miraculous “sensor” requires a hatched fill and not a solid fill?

If you can not wait for the new features being in a stable release then you will either need to use the nightly build or one of the already presented external tools.

Actually, there is another reason to use the hatch pattern. Some boards that have very heavy copper in some areas while very little copper in other areas are susceptible to over/under etching, so a more uniform copper area makes the fab easier and less chance of wrong trace widths. This is particularly true when using large copper areas and fine-line (.1mm ) traces.

You can import graphic onto copper layer as footprint and drop that footprint on the board. I think that covers your use case.

I was told that unbroken copper could cause the copper to be lifted by steam or make the board warp

If that was the case how would solid copper power planes ever work? For rigid PCB’s hatching has never been necessary. However, if you have large areas of the board with open space or few traces your fab house may want to use copper “balancing”. This is where small disconnected copper shapes (usually 2mm round dots) are added to fill in the blank spaces. This is to help the etching of traces however. It has nothing to do with board warping. I have only ever used hatching for flex circuits, but even there solid copper can be used if the area is completely filled, such as a plane layer.

I am not suggesting that this is a real current requirement. I was told this back in the days of solderwave and when there was a lot less attention to storage of PCBs and components before assembly

What is missing in KiCad Gerber file setup is the ability to include any layer - one or many - as input to the file generator. Gerber is dumb - it has no idea what you are feeding it - copper, text, graphics, etc. There are many instances where one needs this capability. Multiple but separate grounds is a common example - at some point they need to combine; known as a star ground. So you draw the ground nets, or planes, on separate layers and combine them at the Gerber level using some sort of a graphic “bridge” to tie the nets together without giving DRC a massive headache. Workarounds like this require the ability to generate Gerber files that can contain multiple layers. Most modern systems have this capability - look at Eagle.

An alternative method is to draw what you need on an inner layer and communicate with the CAM department at your fab house, requesting the appropriate Gerber files be combined at that level. It’s very easily done with modern CAM software.

Good luck! - bdh

If you are brave then yes.

The correct way to do this is with so called net ties (Allows connecting two grounds of different names at one specific point. So you can have an AGND and DGND and connect them at one point. Or you can have GND1, GND2, … GNDn and connect all of them at a single point using n net ties.)

Agreed. “Some sort of a graphic” = Net ties. Are there net ties in KiCad?

I erred in stating that different ground planes had to be on different layers. Many times they are on the same layer. We didn’t always have net ties or graphics. I used to run a captive prototype shop at a large company back in the early to mid 70s - pre-PC. Our engineering folks had one of the new-fangled CAD systems which they used to make colossal errors that sometimes had to be corrected by an engineer running into the proto shop with a roll of red mylar tape and quickly making manual changes to the artwork positives. Things have improved slightly since then…

Right now kicad does not support net ties as first class tool so one needs to go via a workaround of using symbols and footprints. (The next release will add net ties as a separate tool making them more powerful.)
Symbols are in the Device lib and footprints in the NetTie lib.
Simply search for net-tie in the symbol addition dialog.

Something to keep in mind is that the net tie workaround is limited to outer layers because footprints are limited to outer layers.

On an inner copper layer you would use tracks drawn with “ignore drc violations” plus possibly graphics on that copper layer to achieve something similar to net-ties (even worse than the footprint workaround as drc will complain about it and you can therefore miss a connection that should exist.)

Related to the original question, maybe it would help:


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