Applicability of macro 3D printing for nanomachine prototyping
Atom aware bulk limit
FDM 3D printing (FDM ... fused deposition modelling i.e. printing with molten plastic from a nozzle) works nicely in the atom aware bulk limit (that means beside other things exact locations of atoms remain unspecified but the main crystallographic angles and orientations are preferrably used).
- keeping all surfaces parallel to the main crystallographic planes avoids introduction of irrecular steps when the bulk model is refined to an atomistic one
- the ~45° overhang limit for FDM (gluegun) 3D-printing -> similar situation in nanoscale => scaled down models stay makeable
- makro assembly using no sticking force at all only shape locking => assembly of nanoanalogous models may waste energy but will work
Things to note on emulation of nanoscale VdW sticking for makroscale models.
- Note that there is always a sucking force when two coplanar flat surfaces contact each other. It points toward the sliding direction in which the contacting area grows fastest. (wiki-TODO: add image)
- Avoid contacting two large planar or complementary in direct approach - (high force energy wasting snap) - try to slide them onto each other instead. (1D to 0D locking can be done near reversibly (wiki-TODO: make a demo))
- Gravity can emulate VdW sucking but only downwards (anisotropically)
- Tiny magnets can emulate VdW force (albeit in a very limited way) - additional manual assembly effort
- Shaking can emulate thermal motion as long as no free energy is extracted
- makroscale friction (from spring force) to emulate VdW forces - bad idea - very different behavior
- makroscale friction (from tight clearances) to emulate VdW forces - very bad idea - hard to predict friction strength
- makroscale ratcheting (from spring force) - very good idea (this is actually friction on the nanoscale) - designs should aim to make all energy recuperable i.e. no click sounds - unlock move lock
Atomistic models (i.e. where the atom locations are specified and visible in the model) are more useful for visualization advertisement and educative demonstration of principle since the character of the short range force are not accurately recreatable at the macro-scale.
Magnets can provide a very very crude approximation that may in some cases suffice to demonstrate a principle like e.g. superlubrication, soft force-field gear-meshing, a combination of both or other things. There's also some external work to hands on model some early stage nanotechnology protein folding for FDM printed models. They call their models peppytides. Template:WikiTodo
Full color gypsum powder inkjet style 3D printers (service offered by various printing services) are ideal for reasonably small purely visualizing parts which no attempt of force recreation.
The author of this Wiki (about) conducts a meta project that aims to build up a collection of 3D-printable 3D-models (mainly in atom aware bulk limit) that will hopefully turn out to be useful in the development and understanding of advanced nanofactories. See main article: The DAPMAT demo project