Outline graphics challenge w/ KiCad’s internal drawing tools

Hey @eelik, don’t get your feelings hurt.

You want to support KiCAD by showing off its features, I think that is awesome!

My only point is to make your work count for something!

Which is better:

A trivial design no will use for anything but maybe a youtube video and brownie points on a net forum for a few hundred very geeky people?

A set of KiCAD templates for COTS project boxes that end up attracting users to KiCAD because they are using that case?

How about a case company that adds KiCAD links to their website because someone made KiCAD PCB templates for their cases?

You decide what you do, I only suggested what I saw as an opportunity for someone that wanted to show-off KiCAD’s latest features to “make some hay” for the entire project.

I appreciate your contributions here @eelik, So know I support you whatever you decide to do :slight_smile:

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Thanks!

But I still will keep it for just for educational purposes. A library of nontrivial outlines - like the most “curvaceous” ones suggested here - should be done with a real CAD software.


Some news about the situation:

Experimenting has already led to several bug or wishlist reports. Mostly about the new snapping point feature (new in 5.1, post 5.0). Some have been fixed already. If you want to see a teaser video, check for the lately fixed and reported bugs :slight_smile:

Drawing the boards which can be drawn with KiCad is easy; making a basic screencast is easy; making it good for educational purposes is difficult. To be fluent and easy to follow it needs to be pre-planned. It would be best with voice-over but my spoken English is worse than written. Subtitles would be good even without voice. Maybe the video needs to be taken in shots and edited. Learning, learning…

Certain limitations of KiCad’s features have become very clear. For the needs of those more complicated outlines the worse is probably that it seems to be impossible to keep one end point, the radius and angle of an arc fixed while moving the other end. Therefore my original rules (or a bit relaxed) for arcs look actually well justified. Unless, of course, someone gives some useful tips which enable more complicated arc handling.

To some it up, I’m on it, but this will take time. Meanwhile I would still like to see proposals somewhere between the simpler and the complex ones in e.g. dchisholm’s post.

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Complicated arc handling might for now be a bit too much for kicad internal tools. But luckily we have stepup for that.

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How about a parabola - start with something easy.

Do you mean an arc of a circular segment which continues with straight lines? Real parabolas in general aren’t of course possible, and I don’t know if they are in any CAD software.

Conic sections are possible in a number of mCAD systems.

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Splines are well established in several cad systems.
They are popular because input is easy for the user.

While these capabilities are intellectually impressive I’m not sure they truly add much to a tool like KiCAD - especially given the tolerances typically associated with circuit board manufacture. I would be overjoyed if KiCAD could place two arcs (with 3 or 4 options for how to specify the arcs), place a line tangent to both arcs, and trim off the leftover bits of the arcs and line.

Dale

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Yes, but short straight lines so it approximates a parabola. Or indeed any curve.

I think in fairness to @eelik, the intention was to try and show some typical use cases without trying to make this an impossible challenge. The drawing tools have improved in recent versions but they are not designed for difficult CAD layouts like that polycurve ‘Polycase’ design. Nevertheless, it should now be easier to design slightly trickier layouts and I think trying to showcase something beyond a simple rectangle is a very laudable goal.

I think the view is that for complex, tight tolerance, boards using a dedicated CAD program and either a DXF import or @maui 's excellent StepUp workbench is the best route to get an accurate board outline into pcbnew. This is the same workflow as in commercial tools like Altium so expecting this functionality in Kicad is probably unreasonable. Whatever drawing tools are bolted on are sure to upset someone, so it is far better to allow users to use the tools they (or their drafting department) are familiar with.

Back to the challenge - I think it would make a good FAQ to demonstrate even how to do a simple rectangular layout - i.e. how to use the grid and spacebar to achieve an accurate and watertight outline. In terms of a more complex board, something like this would be the most I personally would probably want to try to achieve within KiCad - a walkthrough of something like this would be helpful. The constraints on sizes and units used etc are immaterial to the actual process - Iam not asking anyone to make this for me - I would be interested in seeing their design approach using the new tools.

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I don’t see any reason for that kind of exercise. Those who need complex curves can approximate them using the simple techniques which can be demonstrated with simple outlines if they really want to do that. Or use 2D CAD software like FreeCAD+StepUp which has already been mentioned. But it’s completely out of scope for KiCad itself.

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This is exactly what I want to do, and your picture is a good example. Basically it has the same features than the simple one in dchisholm’s post. You don’t happen to have dimensions for that, do you?

I fully agree with @John_Pateman here. I would make a simple rectangular board with 4 mounting holes as an entry level tutorial.

You could explain why mounting holes should be made with single pad NPTH holes instead of circles on the edge cuts layer. (Bonus would be to explain in which applications plated mounting holes could make sense.)

Another bonus would be a slightly more complicated outline (or even just a section) where you show how to make rounded right angle corners. For inside corners you could even explain that it is not possible to make a sharp corner here (minimum milling tool size)

Your very complex outline could then be a showcase part at the very end. This can then seen more as “This is possible” and less as “Lets make this complicated thing together” (Will take away a lot of pressure as you then do not really need to explain much.) If you include the drawing you used as a basis for this part then interested users can take on this challenge for themselves.

At the end point to one of the great videos showcasing stepup for more complicated outlines.

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haha, no worries, but just for clarification this is exactly why I call it Opensores™ software. Nobody ever wants to treat the wound, just the itch.

A suggestion; re-make one of the small single board computers such as the Raspberry Pi
or Arduino. Some of them have irregular outlines. They are fully spec’ed and non-trivial.
If they are too complex then some of their accessory boards also have unusual outlines
and simpler circuits.

I tend to do a lot of RF work, so the ability to make complex curves like that would be very useful. Normally for tracks of course rather than board milling. Kicad can’t easily do this as far as I know. Something like an interdigital PCB filter would be very difficult to draw. Some examples in this link.

https://nebula.wsimg.com/59865b9b6f9bd6c1514b327a91c6bdfa?AccessKeyId=DAA432FA80C5DABC0234&disposition=0&alloworigin=1

@morganfeldon @G0MJW
this topic is focused on the challenge to create a medium complex pcb edge using ONLY KiCad’s internal tools.
I changed the title of the thread to emphasize the concept.

@G0MJW
for RF footprints, you may consider to have a look at here

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Hi @eelik- Thanks for working on this! I can’t wait to see how it comes out.

Regardless of the final video(s), I just wanted to drop a public thanks for the excellent bug reports that have come out of this exercise already.

yep. Opensores. And not a soul here seems to get why I say that.

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