Printing A Wrench, Ctd

Jul 15 2011 @ 4:40pm

by Patrick Appel

A reader writes:

I work in a "Rapid Prototyping" lab at a large aerospace company where we've been operating a small menagerie of such machines for 15 years. It IS pretty remarkable technology, and it IS advancing very rapidly, but it ISN'T the replicators from Star Trek. Yet …

The printer shown is known as a "3D printer", and there is a Scrabble vocabulary of other types: SLA, SLS, DMLS, FDM, LOM, etc.  They all work on the principle of building objects layer-by-layer by applying energy (chemical, light, heat) to a material (liquid, powder, solid feedstock).

What that viral video glosses over is the part where the man says "you can get strength by infusing this with a little extra resin", which actually means "Well… a  three-year old could bite it in half right now, so please don't drop it until we've pressure-cooked it overnight in epoxy resin– except for the moving parts, which we don't want to glue to each other."

The upshot is that you could buy several stainless steel, lifetime-warranteed wrenches for what that 3DP model cost. But still, printing colored objects is cool.

With a few exceptions (Direct Laser Metal Sintering, Ion Beam Deposition) these processes build with plastics and polymers that are not very durable for actual use, but make perfectly good mock-ups, models, test parts, special tools, molds, fixtures, etc. We certainly are in high demand where I work.

But, the advances in material are happening quickly and we are likely to see something akin to "3D Kinko's" in the near future.

For a more interesting and whimsical look at what to expect, watch this superb 4-minute animation.