Extruding chocolatey treats from your 3D printer may sound impossible, but surprisingly you can do it fairly easily with a little ingenuity.
Many of us have watched, mouth watering, as confection creating machines have appeared on the web. The price of admission in the chocolate printing club, however, has far exceeded our desire to have such a single purpose machine. However, those of us who already have a 3D printer might just be in luck. As it turns out, creating a quick and dirty chocolate extruder isn't that difficult!
As you can see in the video, the chocolate extruder consists of a syringe, a bit of hose, an empty water bottle, and a bicycle pump. You can use the bicycle pump to fill the water bottle with air. The pressure is released into the syringe which forces the molten chocolate out. Printing onto a cold plate allows the chocolate to re-solidify between layers. However, as Jonathan points out in his blog, this doesn't work after the prints get too tall. The layers just don't cool enough to harden. If you want to print taller things you'll have to rig up a cooling system.
For what could easily be cobbled together in a few minutes, I'd say this is a very cool addition to any 3D printer.
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