In the past few weeks, life got a little bit in the way of my maker-hobby. To make sure I got my monthly doses of tinkering, I decided to take on a quick and fun one hour project this weekend: solving a hot and sticky situation.
A few weeks ago I quickly fabricated a simple 18650 charger by soldering a TP4056 charging module to a Keystone battery holder. I used my hot glue gun to keep everything together.
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Not my brightest moment: the TP4056 charger module gets VERY hot, resulting in melting glue. Ending up with a desk full of glue after the 18650 battery was charged. I facepalmed so hard, I forgot to take a picture of the hot and sticky situation.
3D-Printing to the rescue!
Owning the 3D printer, the only obvious solution is to print a mount for the 18650 Keystone holder and the TP4056 module. If you search Thingiverse, you’ll find a lot of these mounts, but of course there is no fun in downloading a ready made model.
Let’s design my own version!
To make things easy, I’ve downloaded a model of the Keystone holder as well as the TP4056 module from GrabCad.
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After importing the step files into Fusion 360, I place the models as desired, allowing me to design a holder around them.
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With a few sketches and extrusions, the holder begins to take shape.
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After adding some mounting holes and and slot for the wires. The design is ready to be printed.
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Aside from some minor slicing issues at one of the corners of the design, my Lulzbot Mini did a fine job of printing the design I just made.
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Time to put everything together!
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The Keystone holders I use don’t have the little trough hole mounting pins, so I used a few pieces of double sided tape to keep the holder in place. I also soldered two wires to the connectors. And soldered those wires to the battery connection points of the TP4056 module.
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Because I wanted to use 4 screws to mount the TP4056 module, I needed to use a little drill to make the holes a bit wider. After drilling I cleaned up the burs. And more importantly: after screwing the module into place I checked for shorts using my multimeter because I used metal screws. Everything good to go!
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Time to start using this handy little fella!
If you want to print this mount yourself, check out the STL file on Thingiverse. Happy Printing!