I found some cheap small microswitches on AliExpress, working backwards I found the same switch part numbers, and subsequently found a Switch Data sheet for the same size part.
I use a mix of Fusion 360 and KiCAD for design, so I CADDed up the three flavours of microswitches, using the dimensions and land pattern from the data sheet:
The Procedure I followed was as follows:
- Open KiCad, into a project where you want to use the components.
- Open ‘Symbol Editor’ » ‘File’ » ‘New Library’; I chose to put them into my project and make them a ‘Project Library’
- ‘Little Switch’ now appears on the left hand side of the screen
- Since a SPDT switch is a common item, I ran the search for that rather than drawing my own this time, and double clicked to load the first one to check that I was happy with it.
- Right click to save a copy
- I selected the libray I wanted to save the file in, and since the Microswitch is a ‘DF-M Series Micro Switch’ I saved it as such
- Back to the front screen (still inside your project):
- Like before you will want to save the new library: ‘Footprint Editor’ » ‘File’ » ‘New Library’
- Find ‘Little Switch’ on the left hand side and right click » ‘New Footprint’:
- Since the first one I am going to draw is the ‘A Type‘ I have chosen to call it that,
- The following gets auto populated on the screen:
- Select the ‘Pad tool’ and place down three pads in roughly the right place, I have also moved the auto populated parts as well.
- Using the data sheet land patten as a guide
I now use the pad » right click » ‘properties’ menu to fine tune the pad’s details:
- Check the layout and mark it up:
- A bit more drawing latter, using the ‘Add Graphics Line’ on the silk screen layer we have now got the A-Type drawn approximately as per the datasheet
- Now we can use the A-Type we have drawn to start working on the other two, Type C and Type D. Right click on ‘A Type’ » ‘Save as’
- For the Type C, and D we will mainly just want to move the outline box to indicate the way the switch lays.
Since this post is getting a fair bit long, I will write another one about how to import the 3D model, and make that all pretty!