Parametric magnetic wire connector (FreeCAD)

Inspired by "universal battery hook und connector with magnet". There were many comments there asking for this model with other sizes of magnets, so I thought, why not to spend some time on FreeCAD practice again :)

I didn't make the exact copy of that model and made my own design.

You can connect wires from the side:

Or from the back of the connector:

The back connection is more reliable because the wire is bent 90 degrees and won't fall out. I don't see any sense in adding a fixing screw here because when you pull the wire, the magnet disattaches before the wire tears off at least when using the back wire connection. If you prefer the side connection, you can always fix the wire with a hot glue from the outer side of the shell to make it more reliable. Or just bend the tip 90 degrees to the down hole (you need delicate fingers for it). I don't see any reason to make it rock-solid: This connection is temporary and should only be used for fast testing. DO NOT USE IT WITH HIGH CURRENT! Regular wire connections should be more reliable! 

Default STL is generated for D5x2.7 mm magnets and 1 mm wires. I have only these magnets to test. Using SpreadSheet in FreeCAD model, you can customize:

shell - the shell around and under the magnet. Recommended values: 0.8 (default), 1.2, 1.6, 2.0.
magnet_d - magnet diameter. Add 0.05-0.1 tolerance.
magnet_h - magnet height.
magnet_outside - uncovered (visible) part of the magnet above the shell. In some cases it can be printed slightly less because of the slicer approximation to 0.2 mm layer height, so it's better to add 0.2 to the minimum required value if you use values < 1 mm here. Default 1 mm value works fine in most cases.
wire_insulation_d - wire diameter with insulation. Add 0.1-0.2 tolerance.
wire_inner_d - wire diameter without insulation. Add 0.1-0.2 tolerance.
magnet_removal_holes_d - diameter of the magnet removal holes. Set 0.01 if not needed. You can remove the magnet by pushing it through the holes with a sharp object such as a paper clip:

This is useful of you try to find the best tolerance to fit the magnet inside the shell or just want to change the wire to another one.

Assembling:

1) Print the connector. Use 0.4mm line and 0.2 mm layer height. You can decrease the layer height to 0.1 mm for extremely small magnets and wires to get more precision. Use slow speed if you print connectors for small magnets (10-15 mm/s).
2) Clean the tip of the wire.
3) Push it from the back till the end.
4) Bend cleaned part of the wire so that it lays into the half-pipe on the bottom.
5) Push the magnet hard so that it won't fall off by itself. If it falls off, use glue or better reduce magnet_d tolerance and print another connector.
6) Upload the photo of your make to the “makes” section of this site :)

I printed only for D 5 mm magnets and D 0.5 mm and D 1 mm wires. This magnet size is enough to hold the weight of an AA battery (actually it can hold 200-300 grams).