How does one import a mechanical drawing for the board into KiCAD

Brand new user here. Started yesterday. Been reading the docs but am puzzled on this. I am designing a PCB and need to specify the outline drawing, various holes for mounting and standoffs, etc. I have access to and know FreeCAD, so I can easily make a 3D model of what is needed. What I do not know is what formats KiCAD will import, nor how to tell KiCAD where there are keep outs, or things like that. Can someone provide some insight? I am reading the V6 docs, since that is my version. So far I have found nothing on what file types are acceptable, or what are the necessary and sufficient requirements for the import. I have no old boards to import - I am starting from scratch.

My schematic is nearly complete save for a couple of decoupling capacitors, and a dopey electrical design rule error. I have placed the footprints in PCB Editor. To start doing anything serious, I need to account for the mounting holes of the display assembly I plan to install. (ILI9341 SPI touchpanel display). I plan to do a 4 layer board, just to have decent power bypassing.

As with software of this nature, there’s a steep learning curve, especially if one is coming from other disciplines. Please forgive me if I use the incorrect terminology, I’m trying to learn it, but it’s quite new to me. Thanks.

Here’s my tut on doing it… with FreeCAD

Another good approach if you are familiar with freecad is to use the Kicad StepUp (KSU) workbench:

1 Like

Thanks for the video. What is the gist of this? Create a 3D board model (basic FreeCAD workflow). Choose the view that is appropriate, make a TechDrawing with all the dimensions and export to dxf? Is that basically it? Without words in the video, or captions, it was a little hard for me to guess what the point was, but is that the basic idea? Say there is a hex hole in the PCB, how does the layout tool know to stay 3mm away and 2mm away from all other edges? Where is this specified? In what tool? Can I also assume that all dimensions should be in mm?

Thanks for the links. I saw reference to this, but didn’t follow it through. I can create the models in FreeCAD - I’m somewhat proficient using it. Did a partial model of my lathe, so I could add a stepper motor to it. Machined the parts and installed the stepper motor.

I don’t want to model everything in FreeCAD, basically the board outline and any mounting holes or hardware, especially for the touch panel. I can let PCB Editor handle the rest. Of course, the easier it is to move back and forth, between the two software packages, the more I would use it! I will look into this link. I’d rather stay in 3D land than export to DXF, if at all possible. Last time I exported to DXF it didn’t look right. I am using FreeCAD 0.21 from git.

The video contains the full process but, if you already know how to draw a sketch (for a 3Dmodel). You don’t need to Extrude (Pad) it - all you need to do is Export the Sketch as DXF then, import it into Kicad.

But, if you want a nicely dimensioned Drawing, TechDraw will be the Workbench to do that…

Standard way in KiCad would be to have a symbol of that display added to your schematic and you should have footprint of that display (containing all holes needed by it) linked to its symbol. Then after Update PCB from schematic you will have that footprint at your PCB. So whenever you move it to the different place all holes to fix it will be placed correctly.

Thanks. I don’t have a footprint of the display, just yet, but I have the part and an incomplete 2D drawing. I could make a 3D model of the display, but the important bits really are the pin spacing and the mounting holes. Could I use FreeCAD to make the 3D model and import it into KiCAD? I really don’t know my way around in KiCAD yet. Temporarily, I just used a single inline connector and wired up the pins. I will mount a header socket on the board and plug in the display, which has male pins.

KiCadStepUp Workbench has been installed. Don’t have much idea how to use it though!

Holes and Cutouts - You can include them in the PCB-shape and/or as Stand-Alone items (exported as DXF). The Video shows both.

Kicad is a bit funky with respect to DXF. The only time I have problems with DXF/Kicad is when NOT using the DXF’s exported from FreeCAD and LibreCAD

Again, if you can Draw in Sketcher Workbench, and export the DXF and Import into Kicad, all should be good.

Regarding ‘Closeness’ to other items; that’s all on your end (your needs and reqmt’s). You can dial-in exactly what you want by doing it in FreeCAD and dimensioning the Sketch (in sketcher, it has dimension tools). Thus, the imported DXF will be dimensionally accurate.

Additionally: Footprints can have Cutouts and Holes…etc on the Edge-Cut layer (and/or can be Moved to/from layers as needed). Thus, if the Display Footprint has the Holes on Edge-Cuts layer, you won’t need to draw those holes. If the Display’s holes are on a different layer, you can Move them to Edge-cuts or draw new ones (on Edge-cuts layer) using them as a guide

If problems, look at the FreeCAD pref’s Export panel and check settings Screenshot of my pref’s

I suspect you have all the skills needed to quickly adapt them to Kicad so, play around a bit. The same is true for using StepUp…

I don’t include details and audio in my vids - I expect viewer to be curious enough to take what I post and explore enough to gain the knowledge needed…

Thanks for your confidence! Kind of struggling a little with the PCB specific jargon. What is the edge-cut layer?

Found I had started an outline of the display module. I have the mounting holes in place but not the signal pins. Guess I will add them.

Yes, best to include the mount holes in the footprint(s) so they stay in the location as you made them, regardless of where you move the Footprint.

It will be helpful for you to read a some of the Manuals - though not updated to reflect current Kicad, the basic’s are well-enough presented for you to understand things like Layers, Edge_Cuts, Cu.F…etc

Just a cursory review to capture the basics (i.e., no need to read about things like “Length Tuning”…etc…)

I’m sure there are many Youtube video (if you can wade through the garbage…)

This is the physical edge of the printed circuit board. It also includes internal cut-outs.
Sometimes called mechanical layer.

Board outlines (Edge Cuts)

KiCad uses graphical objects on the Edge.Cuts layer to define the board outline. The outline must be a continuous (closed) shape, but can be made up of different types of graphical object such as lines and arcs, or be a single object such as a rectangle or polygon. If no board outline is defined, or the board outline is invalid, some functions such as the 3D viewer and some design rule checks will not be functional.

1 Like

You can. But it is ONLY 3D model. Practically not needed :slight_smile:

I came to KiCad from different PCB design program (Protel). I have never before used any 3D model. And I didn’t know that I may need them for anything. When I sow 3D PCB view in KiCad i thought - it would be cool to add such picture to my PCB documentations. Because of it I learned FreeCAD a little so I am able to make 3D models of elements. But my use of them is only to get a semi-photo of PCB.
I think you should forget for a while anything about 3D and just use KiCad alone. In my opinion it could be simpler that starting from cooperation between KiCad and FreeCAD. Others, of course, can have other opinion.
Start from learning how to define symbol and footprint. It is simpler than doing PCB.
In symbol you have to place pins giving them the unique numbers. The rest (including pin names) is only graphic important to human, not important to KiCad. In footprint you have to place pads and give each of them the unique number (the same as pin numbers in the element symbol (symbol is element at schematic, footprint is element at PCB). What you add at Silks layer is intended to be (white) printed at PCB. At CrtYd is the rectangle showing the space occupied by element (it is mainly to help you to place footprints to one not disturb another.
All my symbols have footprint linked to them so after having a schematic (annotated - means each element has unique reference - like R1, R2,…) I ‘Update PCB from schematic’ and have all footprints at PCB. Many KiCad symbols don’t have footprint linked as they can be used with many different footprints so before ‘Updating PCB from schematic’ you have to select footprint for each symbol at schematic. I have never done that step.
You have to start from making your own libraries (at the beginning - one for symbols and one for footprints). Footprint library is simply directory, and each footprint is simply file (text file). So you can make the library using file manager and copy there some footprints from KiCad libraries and you will be able to edit them. You have to add your library to library list seen by KiCad. I don’t want to write exactly how to do it as I am now at PC with Win7 so I have KiCad V5 here (V6 needs Win10+).
Look in menu for Manage footprint libraries and Manage Symbol libraries. Symbol libraries are more complicated as there are many symbols in one file.
In my opinion exporting anything from FreeCAD will not help you much at this stage because things really needed by KiCad are simpler to do in KiCad. FreeCAD knows nothing about PCB design.
Hope it helps.

Thanks for the explanation, greatly appreciated. It seems I can make a simple board outline with mounting holes and simply import it. Think I can do that!

1 Like

My background is different. I used Mentor Graphics in the 80’s for some PCB design. Did some of the first rules based routing at our location. The software had some bugs in it and I worked with MG to get it to work right. Had first pass success on my board, so I cannot complain. Practically speaking I haven’t done any PCB design since then, so I understand most of the basics, but am very rusty on the details. I never had the opportunity to make symbols or footprints back then, since our company had a whole group who only did that. So I don’t have any ancient experience to draw from.

Can you point me to any tutorials on footprint creation? Hopefully V6, so I don’t have the considerable distraction of finding the equivalent method that an earlier version had? In my experience, having old docs is a large barrier to learning the current tools for the first time. New users do not have sufficient background knowledge to make the leap that experienced users can. Are there any videos on this process? I prefer to learn from written docs, but sometimes a video can be very helpful. I learned FreeCAD by watching 3 weeks of videos, often played back 10’s of times, to catch the magic step that I missed! At least for FreeCAD, there were a lot of concepts that were not written, but were exposed in the videos. My learning style is to start with the concepts and learn them cold. In 3 weeks, I was proficient enough to do things on my own. Cannot say I am an expert, but I have completed 31 models and fabricated more than half of them this year, including an electronic lead screw system for my lathe.

My problem those time was how to run Racal-Redac (PCB design program) distributed at 4 360k floppy disks at my IBM-XT without HDD (was too expensive) hawing only 2 floppies and 640k RAM. And I did it and designed PCB working with B&W ‘monitor’ (small TV changed to monitor by me).

Me too. I have read all KiCad documentation pdfs before even downloading the program itself.
Read everything from here:

starting form ‘getting started’.
FAQs at this forum can also be good source of knowledge.
About video I can’t say anything. I just use only written documentation.

You can also find mounting holes to place on your schematic in the schematic library titled “Mechanical”.
Then associate a size and type from the footprint library “Mounting holes”.


Just in case you miss this part in the “getting started”:
All created, modified and imported (from 3rd party), footprints, symbols and 3ds must be placed in “personal libraries” to use in Kicad, so, you need to create personal libraries before creating footprints and symbols.

If you view this tutorial of mine, at 11 & 1/2 minutes into it, the Kicad Footprint Making starts…

Use the ‘Cog’ in the play window to change play speed