Bar-top Coin Operated Phone charger

Over a period of about two years, my chargers have been used, abused and generating money in a wee Scottish bar- now I've decided to release the design into the wild!

Pop these chargers somewhere where folk sit, have them put a coin in the top and they can charge away for multiple of 15 or 45 minutes!

How much money could I make?

I set the goal of making £3 per day- over the course of the year this would make me just over £1000. Footfall is king- the chargers are super eye catching with their lights glowing, they just need someone to sit in front of them to start making money!

The coin mechanism is gravity fed and will work as well as your print quality- currently it is keyed for British £1 pound coins and 50p sterling. This may fit other countries coins- if there is enough interest, I will release future iterations of the design keyed for other countries coins.

Printing

The print is designed to be print in place, meaning you can print the whole thing in one go, but it means you will have to do some post processing work so make sure your flush cutters are standing by. In an effort to speed up printing times, reduce material use and increase the strength of the final design, I've made several cut outs for plywood inserts so in addition to the electronics you'll need a small quantity of 3mm plywood to complete the build.

I've provided a bill of materials to give you a guide to what parts you will need to order to complete the design. I'll also tidy up my arduino code and upload that too- I'm not a programmer so no doubt you will be able to write something much more elegant, this was just cobbled together from various sources, apologies!

I designed my first ever PCB for this design - depending on interest, I'll release the design files so users can order their own PCBs from online manufacturers. Alternatively, my early designs used perfboard and this works perfectly well, just involves a bit more work.

Printing Tips

This is a looooooooooooong print, with challenging overhangs- you will need to have a well calibrated machine to successfully finish this print. Bed adhesion is critical and, as you'll be printing for a long time, you'll need to have a lot of confidence in your machine!

The Design in Brief

I gave myself the following brief for the design; it should be print in place, two units should fit on my build plate and, in turn, two units should use less than 1kg of filament. These goals have been achieved with varying degrees of success but I'm happy with how it turned out.

Notes on the Coin Mechanism

The coin mechanism is gravity fed and uses a simple physical test to ensure coins are coins. This means that if someone went to the trouble of getting the exact right size of washer, they could trick the charger into giving them credit. Regardless, during their two year operation, this has never happened, with users finding it easier I guess just to put a coin in than to bring washers to the bar with them!

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