Tree resin printer:
My second concept is a 3d printer that is affixed to a tree trunk and taps into the trees resin. The resin differentiates from the sap in that the sap is what is in the core of the tree to carry nutrients up and down, whilst the resin is what comes out when the bark is pierced or damaged to heal the tree and is derived from the sap. The resin is collected by the printer heated to approximately 150c and then cooled to the point where it can be fed into a print head to create the model. The resin is treated like rosin obtained from pines and some other species (mainly conifers) where by the fresh liquid resin is heated to 150c to vaporize the volatile liquid terpene components and then cooled and set into a solid. At room temperature rosin is a brittle solid but it melts again at stove top temperatures. It is used by many people including violinists and gymnasts to promote friction. The data input could be collected from the tree itself or trees around it to present an info graphic of the state of the forest in some manner.
Molten glass printer:
There are already several different 3d printers that print using glass. However none of them print using molten glass.
For example the solar sinter by Markus Kayser utilises the sun’s rays and a Fresnel lens to melt sand into glass. Whilst this creates glass like forms, it’s a powdered sintering type of printer that cannot recycle existing glass.
Similarly Shapeway’s method of printing glass uses a glass powder which is bonded with a binder then hardened in a kiln.
My first concept is to print from recycled glass material. A drinking glass that has been broken could be picked up, placed in a hopper where it is melted down and then piped through to a printing head where the glass is then reformed.
There are significant technical hurdles to overcome, such as heating the glass to a molten state and delivering it to the printing head without risking a failure. The melting point of glass ranges depending upon its composition but most common commercial glasses range from 1400-1600 °C. So both creating and managing sufficient heat will be a key component. Heating smaller amounts of glass as it is needed may be the key to a successful design, whilst components will need to be produced out of steel and other hard metals. Like the solar sinter project a Fresnel lens could be used to produce the heat to keep within a sustainable theme, however this would not be as friendly a scale for home use.