I am fairly new to KiCad, after an open source software advocate friend recommended it and then v6 convinced me to try it out.
Even though the internal footprint library seems extensive, I quickly came across a few parts without a footprint.
Example: A fairly common small SMD RBG LED and a few breakout PCBs —essentially squares with several pins. I have some technical drawings with measurements, and calipers .
I wonder what would be a good option to acquire footprints:
Should I be searching external websites for footprints? (I could imagine it would be difficult to judge the quality)
Should I generally try to make them on my own? (Never did it before)
Is it advisable to combine the two approaches?
Did I forget anything?
I would be interested to hear your seasoned advice, even if controversial. Thank you.
I think it is best to acquire the necessary skills to make one’s own footprints right from the beginning. It is not rocket science and footprints from other sources more often than not require some work anyways.
Footprints you are looking for sounds fairly simple (please share part numbers here, maybe these already are in the library but you slipped over novice mistake and cannot find?). I suggest trying to draw your own.
Personally I never (almost) search for footprints when not found in libraries I use, creating new ones is a fast process, but I spend much time on searching for 3d models of the packages. Sometimes it is faster to modify similar existing footprint from standard libraries. Also, you always have to double check external footprint before use according to the datasheet, and this step can be skipped when creatong your own footprint.
A reminder that there is a footprint creating wizard in the editor that handles stuff with regular pinouts (like modules). For instance I used the DIP/SIP wizard to create this footprint:
Regarding the 3D models, I wonder what one would expect from them. Would it not be sufficient to have approximate volumes of cylinders (e.g. battery, above) and boxes (PCBs, connectors, etc)? Or is it to get a photorealistic render of the board before it is made and populated?
It all depends on how realistic you want it to look. If you are trying to fit boards in a box, then you may wish to combine it with the model of the box in a CAD program to check for collisions.
Yes, 3D stuff is fully user dependent. I want to have realistically looking 3D renders (only in orthographic perspective) to be passed to the assembly man (hand soldering), and also for documentation. My boards usually are interconnected inside a bigger system via cables, and I prepare interconnection diagrams of whole system. It is easier for assembly engineer to get idea of what is needed to do when realistic looking images are embedded inside documentation (connector locations of the boards, as an example). Taking photos of real board does not provide orthographic perspective, so some details of the board is missing. Also, real photos have too much details, reflections, perspective distortions and color variety to be used for nice looking documentation.
I do not use 3D for simple, or “single use only” type of boards.
Before getting (few years ago) into KiCad I have never used 3D models. I didn’t know what they could be useful for me.
But when our new contract manufacturer asked for photo of PCB we order I decided to include 3D view from KiCad in the documentation.
I spend some time to discover FreeCAD (never used any 3D program before) to the minimum extent necessary to define 3D element models. The only serious problem I had was with vanishing colors (you have them in FreeCAD but after exporting model you don’t have them) but now I can do models I need. I still don’t know how to check PCB against case - till now never needed it.
Thanks to cheat sheet I need not to learn each time from beginning (I do 1 or 2 models per year).
Two examples of my models (KiCad 3D model preview):
We have our own part library that we use for all our projects. That way if a Kicad library changes a part, it doesn’t affect our projects. Also for footprints, we tend to use smaller fonts and other tweaks from the Kicad built-in libs. Here is my flow:
Does the part exist in the Kicad libs? Copy it to the private Lib and make any tweaks.
If not, is there a footprint in the Kicad libs that is very close? Copy it to the private Lib and make tweaks.
Else, we make the footprint from scratch using the part data sheet and using the Kicad footprint wizard if possible.
If a comparable 3D model (step+wrl) is in the Kicad Libs, we copy it to our private Lib
If not, we try to find the model on GrabCad, 3D Content Central, etc. (mind the license depending on your application); then use @maui StepUp in Freecad to match the Step to the footprint
In my own personal use, I tend to use KiCad’s generic footprints like DIP ICs, SOIC etc, while making a lot of others myself. I may want different spacing, or larger/smaller pads, etc.
Keeping your own parts library of whatever You use most is probably a good idea, which you can backup separately.
As KiCad is mostly for my own personal use, the 3D models don’t bother me so much, but I’m sure creating your own models, even if just to show bounding-box area of a part, could be useful for your own purposes, to check clearance etc.
Personal opinion… No. For me it is too much time and effort wasted.
Yes. Quicker, easier and more reliable. Ease of making footprints and symbols was the main attraction for me.
I nearly always find some suitable footprint (and/or symbol) to modify, “save as” into a personal library.
Modify, move, change number of pads first, then just drag and move the existing, various layer outlines to suit the new footprint.
Smallish stuff can be done in 5 minutes usually, when you are familiar with the editor.
Both the symbol and footprint editors work much the same way.
Yes, you should be ready to create your own footprints!
But it is now always necessary. Have a look at the SnapEDA plugin for KiCAD. It is quite extensive, provides symbols, footprints, and 3D models, and is very convenient to use.
