I do not like being wasteful, throwing things away just because they are a bit damaged or outdated creates a lot of trash and squanders resources.
After my notebook died i was left with a few still good 18650 lithium batteries, and they had to be put to good use.
After a few days the decision was formed to build my own LED flashlight with them, there were numerous plans and ideas on how to do this and in the end, the main problem were the mechanical parts.
My first flashlight was build from an old wooden table leg, two AA batteries, a switch out of an old HiFi receiver and one of the first 10mm red LEDs that had become available.
That was roughly 20 years ago, technology has advanced incredibly far since then.
While I do have a mill and know how to work with aluminium, I could not settle on a design that I liked and could realize with the tools and skill at my disposal.
After a few weeks of mulling over this problem I came across a video about a 3D printer and was blown away how good the parts looked that were made with a very basic cheap printer.
After a bit of research I decided that I would build my Flashlight completely from the ground up and 3D print it.
And since the printer uses PLA, it would not even use up non-replenishable resources.
And once it breaks, the plastic parts can theoretically be buried in your garden.
There were a few design considerations.
- Flicker free, analog dimming and no PWM
- High efficiency, i hate wasting energy.
- Good-ish color rendition, above 80CRI
- Battery level indicator
- More then just one button
- Rechargeable with a standard phone charger
- Low-ish cost.
The electronics ran tough several iterations with OLED displays, Bluetooth, battery gauges, miniature LED matrices as user interface, touch controls, rotary encoders and many more over complicated features.
At one point the entire project was nearing collapse and the decision was reached to downscale the entire operation.
The cooling of the LED proved to be a challenge so it was decided to use active thermal feedback to control the output of the light with a NTC, though this feature has not been implemented yet.
Early designs aimed to make the entire light waterproof but ended up producing more additional problems at this point.
Since I was working with it for quite a number of years already I tried to use Sketchup to model the parts and export them at STL files.
There was a lot of swearing and after a few recommendations I switched to Fusion360.
There still was a lot of swearing but it was worth it and only took me a week to get comfortable with it.
The main body of the light is constructed with 3D printed parts, the print orientation of these was optimized to enable printing without much support material, as well as maintaining a maximum layer adhesion.
The goal was to use only standard parts, no glue and only parts printed in PLA without any metal.
It would have been was simpler to just glue everything together, but that means, you can not repair it easily.
This made the whole construction a bit bigger then necessary.
Threaded inserts, smaller screws and glue would enable the whole body to be much smaller as well as printing it in PETG/ABS for more structural strength instead of relying on thicker parts.
Besides one part, it can be printed with a single type of filament in one go.
The button spacer needs to be transparent, otherwise it will cover up the status LEDs, for the prototype Esun red and Nunus clear PLA filament was used.
Again, PLA is not ideal but was chosen for ease of use and less environmental impact.
The button caps and the button arrangement are not ideal but the main focus was to build a working prototype, the ergonomics had to be moved on the back burner.
As well as the button actuation, the force required is not satisfactory at this point and the haptic feedback is not very strong.
On the initial draft the buttons were comprised of a simple spacer and loose button caps, this proved to be a bad idea in the end.
A new button holder was designed...Read more »