Article from: 3D-printed-beest-hand-cranked-power-generator
As serious hobbyists will tell you, 3D printing riddled with hidden costs, and I’m not just talking about the filament that always seems to run out. Your power bills also tend to spike when you buy your desktop 3D printer, as you’ll quickly keep it running for hours on end to finish a few cool projects. That’s why one Norwegian designer decided to do a little in return through 3D printing. Even Erichsen, of Norwegian 3D printing website just press print. no, has built the incredible The Beest 3D printed hand cranked generator, a machine that not only looks fantastic, but is also capable of generating 30 watts of energy. Not enough to brew a cup of coffee, but it’s still very impressive.
Fortunately, Even was happy to talk to us about this fantastic creation. Even is a 36-year-old designer from Oslo, Norway, who works as a 3D designer at an architectural office. However, he is also an avid 3D printed and is always working on one project or another. As he explained, this is actually the second version of a 3D printed hand cranked generator he was working on. ‘My initial goal was to generate electricity to boil water for food and disinfection... I soon realized that this needs a lot of power! You would have to work the generator for quite some time to boil even a small amount of water,’ he explains.
But what he came up with is still impressive. The Beest is powered up by hand, featuring a cool series of gears: ‘1:2 + 1:4 + 1:3, so one turn in rotates the rotor 24 times. The rotor is set up like a 3 phase axial flux generator, with three stators and six rotor plates with a total of 96 neodymium magnets,’ Even explains. Each magnet holds 15 kg, and the electrical output is wired in series before reaching the PCB. Even as also installed an Arduino that reads the voltage coming in and putting it up on the display. But as you can see in the clip below, it mostly just looks very cool.
But as you can imagine, it is everything but simple to 3D print and assembled. Featuring 60 3D printed parts, Even needed two 3D printers to complete the project: I used my Ultimaker 1 for the biggest parts, and a Makerbot Replicator (Dual) for the smaller ones, he tells us. Taking about 250 hours to 3D print almost everything in PLA, you can imagine what this did to that month’s power bill.
Being a professional 3D designer, at least the design process wasn’t as stressful as it would be for the rest of us. As he explains, the design was intended to merge old and new technologies together, so a lot of inspiration was taken from old cast iron machines. ‘When the crank is on the right-hand side it is only logical to have the mechanism flow to the left. I needed some gearing before the rotor, and it was mostly just a matter of organizing this in the most practical way in relation to axels/structure. I tried out a couple of gearing ratios before finding the one with acceptable resistance,’ he says of the design process.
Designing in 3D Studio Max, Even took care to ensure that all rotor parts were 3D printed in a single piece, meaning that the size of the overall machine was determined by that of his biggest print bed. ‘Other parts were sliced to smaller pieces (in 3d) and then screwed together with nuts and bolts,’ he adds. However, it was largely straightforward after setting up size boundaries, the Norwegian maker explains: ‘In my experience the design (and the whole process actually) takes on a life of its own once you have made a couple of choices.’
But the story isn’t over yet, as Even further required quite a bit of electronics and other parts: ‘[I used] 96 neodymium magnets, about 1,5 kg of enameled copper wire, six steel plates, a lot of nuts and bolts. ThePCB include Arduino Mini, display, LEDs, contacts, switches, capacitors, resistors and bridge rectifiers,’ he tells us. Assembly was also quite complicated, especially wiring the copper coils and placing them inside the stators. ‘I used enameled copper wire AWG 15, and this was a little thick and hard to work with.
I recommend using thinner copper wire (AWG 20+), more turns in each coil also generates more voltage. Another tricky part was making the axels and getting correct placement of the gears. I used 12mm threaded rods and glued the locknuts where I needed the gears,’ the Norwegian making wizard adds.
However the results are well worth the effort, as The Beest is a truly spectacular and inspiring model. If it could now also boil water, it would be absolutely perfect, but even the current state of the machine is a making wonder. While definitely not for suitable for the inexperienced maker, Even was kind enough to share his 3D printable files online, which you can find on Thingiverse here. Should you tackle this project, also take a look at Even’s website here.
Even, meanwhile, is already moving on the next project. Currently finishing an automatized cat feeder, he is even thinking of a perfect 3D printable power generator concept: ‘One where instead of using your arm, you stand upright and use your weight. This will be much more powerful and easy to use than the other two,’ he says. Now that would be a building project we could justify to our wives and girlfriends.