Micro LED Lamp by geit_de

Last crawled date: 3 years ago

Hi there,
This is a little project to up-cycle some old batteries and learn more
on how to use FreeCAD.
Today we create a small micro LED lamp with parts I found when cleaning
up. :D
Requirements:
3 Batteries LR41. (other possible, see notes below)
1 LED
1 Improvised switch by using a metal part, a wire or folded aluminium
foil.
Tools:
3D Printer
Pliers (optional but recommended)
Requirement Notes:
I used metal from an old file for documents. It fit perfectly after
cutting to length.
When using a wire make sure the ends have proper contact. A
single core wire may work best due the fact it gives some spring
effect to the switch.
Using folded aluminium foil may not give the best results.
Adding some paper to fold around may add some more spring effect.
This is totally untested, but works for sure.
You may need to decrease the "roof" of the battery compartment to
gain enough space for the switch design of your choice. However
you can rasp it down to your needs without printing easily.
Printing:
This thing is tiny and the supports may cause trouble. The small
gaps between the battery compartment are required. The one in
the back is to get the metal part through. The first one to be
able to pop out the batteries and fit the LED.
I printed it upside down, but you may want it in any other
direction. The nice part of this project is that it does not
require a lot of plastic, so you learn about the capabilities
of your printer, too. Because of the fragile components it may
also be wise to print at high quality. Again, the part barley
needs any plastic.
Make sure your printer is calibrated or you may get a to small or
to big part.
Assembly:
Assembly is actually the hard part. Since there is no battery
cover, I designed the lamp to be a tight fit. Prepare the LED
first. Easiest way is to place the LED onto the ledge of the
printed part where it will be mounted. Cut the wire without
the goblet (cathode) so it hits the case. Now bend the one
with the goblet (anode) 90 degree inwards and cut it like
shown in the pictures.
Insert the bended LED wire using the gab under the "roof" of
the battery compartment. If done right the LED holds itself
and the small ledge of the printed part will fit perfect
between the LEDs wires. Now insert the batteries with the plus
side facing the LED. Make sure the first battery hits the LED
wire with the front side. Along with the last battery put the
metal part or wire into place and bend the other side, to just
not connect to the other LED wire.
You may need pliers to push the batteries in place. Trust me
they will jump around a few times until everything is in place,
but once you are finished everything is rock solid.
If done correct you just need to push the metal, wire, aluminium
and the LED lights up. If the spring effect is big enough the
"switch" should open the circuit once you stop pushing it.
Notes:
Even though this is just for LR41, you may change the sketch of
the LED lamp to fit any other battery at your disposal.
Since I am still a beginner with FreeCAD the included file may
have some issues, so please don´t blame me. This project only
exists to learn how to design parts and instead of creating
useless cubes or other stuff, I want to create actual
functional parts as kind of reward for myself.
Happy Printing