Where to find electrolytic capacitor 3D model FreeCAD source

I tried FreeCAD a little, but it was one year ago. I just don’t know how to (as simple as possible) add polarity marking to Electrolytic capacitor model. I believe that it would be simplest if I will find the *.FCStd file containing the electrolytic capacitor model and than modify it to get dimensions I want.

Do you know where to find it?

I am looking for FCStd file and not any script generator I don’t know how to use it.

Which cap do you need? There are lots of caps already made with marks.

Dimensions are diameter, pitch and height. And of course if it is smd or tht.

The ones in the official lib are script generated. There is not really an FCStd file that can be edited. But you can add a parameter set for your component to the python script found here https://github.com/easyw/kicad-3d-models-in-freecad/tree/master/cadquery/FCAD_script_generator (I have not used these generators for quite some time so i do not know how to setup the environment with current versions of freecad)

Edit: yes i am aware that you state that you do not want to go down that route but i assume it is still useful information. (As it makes it clear that even the fcstd files that come out of this generator will not be usable to you)

THT 1F/2V8 - φ8 x 15, pitch 3.5
THT 0.33F/5V5 - φ13.5 x 6.6, pitch 5, but legs are not round but rectangles
but I much better prefer to have a way to get what I need when I need.

I found many caps in:
but there are *.wrl and *.wings files. As I understand KiCad should get *.wrl and *.step files. I’d rather not bother him by giving other files than he expects.

It has the potential to be useful information :slight_smile:

This is something that surprised me. Does FreCAD have any other file format that you cannot normally look at? So far I have no success in editing FreeCAD files. It’s easier for me to do something from scratch than to correct anything (that’s why when I do something, I save the file every now and then and in case of problems I go back to the previous version). But I was hoping that when I saw such a file, I would have a chance to understand how it was created.

I had a quick peek at this as I’m also interested in making FreeCAD 3D models for KiCad.

I exported a simple PCB (From KiCad V5.1.9) as a step file and imported it in FreeCAD, then deleted everything except the capacitor.
It’s just a “3D Solid” as a blob. You can look at it and admire it’s properties, but you can’t do much else with it.
I won’t even know how to scale it in FreeCAD.

KiCad does have built in scaling, so as a workaround you could take an existing model and scale that, but you probably already knew that.

It is difficult to modify a Kicad step model with Freecad. I use Freecad to make models from scratch and then export to step with StepUp. Same as Piotr.

But StepUp needs a solid model. I do not know how to split the solid model in its original parts.

Sometimes I have had the other problem: I downloaded a non-solid step model from 3dcontentcentral and there was no way to make a solid.

Maybe it is easier to download a model from 3dcontentcentral and try modifications on it.

A simple search:

brought me back to this forum. A long post from 2015 about 3D models for KiCad made in FreeCAD:

That thread links to the “github / easyw” also already posted by Rene.

Joan Sparky posted in that tread:

right under a picture of a PCB with (among others) a nice looking capacitor. She also states she made all her 3D models herself.

The problem with the capacitor fcstd files that one can get from our generators is that there is no information in the freecad file about how it is made. That part is all in the python script. Freecad only ever sees the final result. (The generators make an fcstd file, a step file and a wrl file but we only keep step and wrl)

This is however different for other models that are purpose made in freecad as found in this repo https://gitlab.com/kicad/libraries/kicad-packages3D-source So while this does not have stuff for elcos in it might be a good starting point for other components.

And you can search this old forum thread. 3D new library for Mechanical CAD exporting and enclosure design I remember that people posted CAD files in it that should be modifiable. But fair warning that thread is nearly 400 posts long so finding something in it might not be easy. And some of the files posted there are made in expensive software not in freecad.

I made a YouTube Video on making Electrolytic Cap in FreeCad - here’s the link

Cap_10µF.FCStd (351.1 KB)
Cap_10µF_r0.kicad_mod (675 Bytes)
Cap_10µF.step (178.9 KB)


Yes, I knew. But I have read (don’t remember where) that except one value (don’t remember which one) you should not use scale, offset and rotate possibilities while adding 3D model to KiCad footprint. I don’t know what problems it can generate but just in case, I prefer not to call a wolf out of the forest (hope that means the same as in Polish).

I have looked through it. I will do some tries but later.
I supposed to get the main C part by rotating the rectangle (you can get the recess around and at top in the same operation). And may be rotating it less then 360° and next rectangle (exactly the same) for the rest of ° you can get the polarity mark. I suppose to get that way separate surfaces to give them separate colors. If not then may be the rectangles will need to be minimally different.
I don’t know if in FreeCAD it is possible to define my rectangle with recesses once and use it twice.
If I will want to have ‘-’ signs at polarity marking I can do it like you get 10uF or may be by rotating next few rectangles for few °. I wonder if I can having them the same radius as the main capacitor body or they have to have a little bigger radius to be able to give them separate color. I suppose if the radii are the same then FreeCAD could not be sure which one surface is visible.
So for main body i suppose:

  • if main rotated 360° and polarity mark few ° the polarity mark have to have bigger radius,
  • if main less then 360° and polarity the rest then probably radiuses can be the same.

I think you’re mixing up some things here.
The KLC specifies that all 3D models should be 1:1 size with the footprints they represent, without any scaling factors applied, and I applaud that strictness because it leads to higher quality libraries.

Re-using an existing 3D model and scaling it to better fit a particular footprint in a single project is a valid method for me.

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I just don’t know in what problems (if any) I can get if I use scaling. Currently I only use 3D to get my PCB picture and didn’t tried to use PCB 3D in any other way.
Just to avoid any potential (unknown for me) problems I decided to have all 1s and 0s for 3D models in footprints.

@Piotr I’m a little confused so, I’m not sure if I understand all you said but, perhaps this will answer it…

• I set the Text to be Offset only to illustrate how to do Text and including the Offset will show users how to do it so they can use the concept to make text on models for 3D-Printing (hoping user’s imagination would kick in)

I added a Datum-Plane (screenshot)

• I added a “+” sign by drawing Two Rectangles on the Added Datum-Plane. I could have done both in one sketch and could also have done it with the ShapeString Text.

I also show Trimming it using a Sketched section (to show user how, in case they want to use the concept on a part that is not round or has items user does not want cut. Vid below

• This time, I set the diameter for the 10µF Trim to be equal to the Cap’s diameter so, nothing extends beyond the Diameter

• Also shown is setting color after item is trimmed to the surface of the Cap

• Scaling: I sometimes use Scaling when making a Footprint or editing (and renaming) one for another purpose

• Reusing items - Can Reuse Sketches, Can Copy/Paste them, Can Duplicate them. Features can be reused, too. Then, re-mapped to desired features/faces/datums… MANY things are possible to do

• Can also ‘Inset’ the text instead of Offset

EDIT: you can also Project a graphic Image onto a Face

Thanks for making the video showing how to use freecad to make an electrolytic capacitor.

I must have missed the tool you used to carve the circle-shaped grooves in the cylinder representing the capacitor. Not surprising–I am a newbie with freecad and have not yet how figured out how to make 3D graphics primitives with it.

So glad to see freecad can juxtapose Greek and latin (English) characters.

How clever the way you extruded text from the cylindrical exterior of the cap., and then trimmed it with two more larger cylinders with axes identical to the capacitor’s !

What key or keys did you press to make the mu symbol in the footprint editor?

I’m not enough skilled in FreeCAD to notice (and even understand written tekst - ‘Offset’ ?, ‘Datum-Plane’ ?) what you are really doing and have not time (now) to stop it very often and check what the tools you are using are for what. Probably I will find some time in nearest days to analyse everything step by step.

What I was writing about if one surface have to be in front of second (the radius has to be bigger or can be the same) came from what I remember from my first FreeCAD (0.18 those time) experiments that if (in Part, not PartDesign) I had flat surfaces at the same plane of two things made of different color material (have in mind that I can wrongly remember details) then while rotating it in 3D it looked that FreeCAD changed that surface color many times during that movement.
I just plan to do some experiments but not now.

The “Groove” tool on Right of screenshot below (the one on the Left will create a solid ring instead of a Cut

The font with " µ " is in Symbol’s font (also in other fonts - user needs to explore their system’s fonts and use of Cmd, Ctrl, Option, Shift keys as they change with a key-press).

v18 is loaded with Bugs and incomplete code!!! I don’t know why they keep it posted… V19 (though a Pre-Release) is what you want to use (it’s been a pre-release for more than 16 months!

Most likely either V18 or, your machine or, lighting-pref’s and/or the usual graphic issues of graphics…

It would be silly of me to comment on what you " don’t " remember, especially if you used v18.

I’ve been using FreeCad since v13 (If memory is correct) and have mastered it quite well so, I just Click, click, and click until the job is done. When I face a problem, I cheat and trick.
Much of what I learned from using SolidWorks, Pro-E, Cadkey and many others somehow plays a role in creative problem solving FreeCad…

Examples: Variable Radius is Not doable in FreeCad unless Trickery and Workarounds are used. Many things common to other Real CAD programs are Not natively done in FreeCad without the Trick’s… But, with time and effort, much can be learned that’s usable down the road…

Not Tooting my horn but, to give you the idea, I dug these Examples out of my ‘How-to-Do-It’ folder…

Screen Shot 2018-06-13 at 9.35.06 AM

helmet2a copy

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Drew outer shape with inner rectangles, extruded, trimmed and colored…


What I was wondering was: if you trim that exactly with the same radius then body radius itself then will you be able to color that surfaces or FreeCAD is not sure if that surface is visible or hidden.

I think that if you read once more what I have written those time having in mind the following picture from standard KiCad Library:

then it should be clearer. The grey polarity mark (including at top - it is important when PCB top-view in documentation should help in assembly) was what I was thinking how to do. My conception was to get the blue body and the gray mark by rotating the same semi rectangle around vertical axis. I am just not sure:

  • if I do the blue 360° then do the gray have to have bigger radius or not,
  • if yes then may be better would be to not have blue all 360°,
  • is it possible to use the same semi rectangle twice.

I am asking myself such questions because I would like to have as simple solution as possible. I just believe then if the file will be simpler then I will have bigger chance to modify it later to get other capacitor dimensions I will need with not unintentionally damaging all during my modifications. For example the best would be to have the radius in only one place. I just expect that if it is in many places then after modifying it in one place and before the next one some surfaces disappear or change the numbering and everything goes wrong. May be for experienced FreeCAD user it is not a problem but till now I spend with FreeCAD in total only few working days and I spend 0 hours with any other 3D CAD program.
I am working now on two PCBs - one will be the module installed vertically at the second one. Synchronization of pin assignments at both of them (and the symbol of one used in schematic at the second) is what I am busy now. It is not simply as I gave myself a task to do all connections (except GND) in both PCBs using only top layer. Connection will be 30 pins of 1,27mm pitch pin-header so no way to go with track between pads.
I know I will use one capacitor that in KiCad library there is not such 3D model. So designing that PCBs I at the same time think how I will do its model. That is why I asked, but I will try to do it after I will finish my PCBs.

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