Finally, 3D printed objects I can really sink my teeth into.
Cake icing seems more manageable as an edible printing material (more like the meltable plastic string). I would think chocolate would take too long to solidify (although you could print molds for it with a regular plastic printer). I'd love to see a picture of their printer to get a better idea of the technology.
But (unfortunately) if they print customer's models, i couldn't see it on their web site (but sometimes internet doesn't work so well where I am).
Rob, I am certain that I have seen a write-up about a chocolate printing process, within the last year, I think. So your idea is certainly valid. But I think that it dispensed a thin stream, not drops.
As for 3D printing with sugar, it would take a thin stream of granules and just enough IR to melt the outside of the grains, so the process control would need to be very tight. Not a real problem, except for finding the exact parameters. Adding any solvent would certainly lead to almost instant jamming because wet sugar is so very sticky. Really, the serious challenge would be in the feeding at a consistant rate. Of course it might just feed one grain at a time, but do it quite rapidly.
Here in the Tampa Bay area I see quite frequently a brightly decorated van with the logo & description of EDIBLE DESSERTS. The van artwork shows various fruits re-formed into figures, etc. So, it would seem that although this 3-D printing is something new, this concept is not new. I'm sure that there are small businesses sprinkled throughout the land that offer this service also.
It's a neat idea and application, and I can understand the inventers wanting to keep it secret, but I'd still like to know how they do it. Given that they start with granulated sugar and end up with granules stuck together, it's some sort of sintering process. With sugar, that could involve either heat or a solvent (water). It seems like heat would carmelize the sugar, but perhaps not. In any case, that would be similar to the laser sintering used for 3D printing metal parts from powdered metal.
A solvent-based sintering process would be more interesting because I'm not aware of that being used in any 3D printing systems to date. Solvent sintering could open up a lot of new applications. It could provide an alternate method of making plastic parts, compared to the plastic wire extrusion that is common. I could also see it used to make intricate structures of water-soluble or other chemicals for use where a large surface area as well as mechanical strength is needed, such as in batteries and catalysts. A chemist may even be able to devise a process by which some chemical reaction takes place as the particles are adhered together with the solvent.
I must say I was disappointed with their website. It's very minimal, it doesn't work well, and the pictures, that are almost entirely close-ups, don't really show much.
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