I hate to be the bearer of bad waistline news, but yes, you can now buy a 3D printer that prints chocolate. The cocoa press has been in development for an entire decade. Now, it's finally here, and I'm pretty sure it's solely responsible for one of the pounds I gained over Christmas.
At least it's still not cheap or easy enough to tempt most people.
This holiday season, I received a $3,995 pre-made printer (you can make it yourself for $1,750 or less) and thirty perfectly fitting chocolate bars to meet my delicious goals.
I plugged in the printer screen, did the setup, popped a dark chocolate “cocoa core” into a cartridge, added a washable plunger cap, preheated the chocolate for 30 minutes, and pressed start. annnnd… I quickly watched as the nozzle tried to eat into her silicone baking mat.
I'm not sure if it was the Z height or the print head getting a little loose during shipping, but after adjusting both, I tried again and got this amazing 3D printed rose:
Just look at that flower. Look at the ridges. Does all that surface melt on your tongue? I can attest that it was delicious, velvety and delicious. It took almost an entire bar of chocolate for this impression, but it disappeared about two minutes later.
The best part about 3D printed chocolate is the amazing textures you can create. 3D printed gyroid filling? I can not get enough. (You can see some examples of that filling in my video above this story.)
And yes, dark chocolate really does taste like dark chocolate, despite using palm oil instead of cocoa butter for its fat, presumably to make it flow better. My wife is very strict about dark chocolate and while it's definitely not the best we've tried, she was pleased with the quality.
But I can't say the same for milk or white chocolate (they're a little waxy and reminded me of Candy Melts) and I've never had success like that first rose again. Because the worst thing about 3D chocolate printing is controlling the heat.
Chocolate is fundamentally complicated to print, and not just in traditional forms of 3D printing. Cocoa Press allows you to set the heat of your nozzle to a tenth of a degree, because to begin with, fractions of a degree can be the difference between hot enough to be liquid or too cold to squirt out of the nozzle.
In my case, the printer's 65 gram chocolate syringe sometimes took hours to reach a uniform temperature. Cocoa Press founder Ellie Weinstein says this was due to a defect in one of my warmers (and she will replace the entire cartridge and warmer assembly “for anyone who requests it”), but the heating may also depend on the chocolate per se. Dark almost worked with the Cocoa Press preset; the milk wasn't much harder, but the white took me most of the day, adjusting it up and down every half hour to find a temperature that would flow.
But even when I got the chocolate to flow well, I quickly discovered that you can't print anything too small or too pointy without drastically slowing down the prints. The chocolate needs time to cool and solidify before the nozzle attempts to print another warm layer on top.
It's easy to see the point at which this Sierpinski pyramid began to ooze:
And it probably doesn't make sense to print a single calibration cube absolutely.
Optimally, you would have slowed these prints down to certain heights to give them time to cool, but right now that's a manual task, not something Cocoa Press can automate for you.
Although small objects are not so recommended, I was not able to print very large objects either, since the 65 grams of a single chocolate bar are not many. Weighing 59.5 grams, that pyramid approaches the limit of a single cartridge.
But you can print sheets of small objects, like these Mario stars I made:
Or you can take advantage of vase mode, where a 3D printer prints in a single continuous spiral, to build something tall but hollow. The rose is a vase mode print, as is the bottom of this mock coffee cup, which I printed in white chocolate for the “cup” and milk chocolate for the “lid” on top.
Or, in theory, you could swap out a new cocoa core after the first one runs out for a longer print… but again, it's not automated. You would have to program it to stop at the right point, or watch it manually and pause it prematurely when it's running low. Even then, you would have to wait for the second cocoa core to preheat before resuming printing.
I tried the change three times. One time, I wasted time and the printer died and kept printing air. It once looked like it would print without a problem, but the print mysteriously failed later. And I once tried to switch from dark chocolate to white chocolate, but the chocolate got stuck inside the nozzle and refused to come out.
In practice, I found it much easier to simply print objects that would consume most of a stick in one go, then use the rest to print a second partial object and just pop it directly into my mouth.
Despite my difficulties, some parts of Cocoa Press seem quite well thought out. I was impressed to see that the printer is supported natively. in the popular PrusaSlicer, that all surfaces that touch the chocolate are easily removable and washable, and that my unit even comes with cleaning tools that fit perfectly. The touchscreen user interface is easy to use, with all sorts of 3D printer enthusiast settings available if you know what you're doing. Andrew sink in Tom Hardwarewho knows what he's doing, I had it better than me.
However, “you know what you're doing” probably describes the audience for this printer. I can't imagine a newcomer to 3D printing would have the patience to enjoy Cocoa Press, even if they were to spend upwards of $3,995 for a pre-made version and $49 per pack of 10 pre-made chocolate cores.
But I could definitely see some DIY enthusiasts spending the $1,499 on hardware, printing their plastic parts on their own existing 3D printer, spending 10-15 hours building it, and learning how to make their own chocolate cores too, just because they could. . .
Photos by Sean Hollister/The Verge
