Frame material
People have built RepRap-based ... things ... out of a surprisingly wide variety of materials.
Most of the mass of the RepRap is the outer frame.
There seem to be 4 main approaches to making the frame:
- build-up: Build the frame out of parts built-up to exactly the right shape and size.
- modular: Build the frame out of some modular construction material, to make it easy to make a little bigger (so you can make bigger parts) or a little smaller (to improve rigidity and hopefully precision) or to otherwise experiment with different configurations. Also, once such a RepRap has been built and printed out the second generation, it can be disassembled and the parts used for other things.
- cut: Build the frame out of some continuous material that is cut to length, and perhaps a few holes drilled in it, but not otherwise shaped.
- shaped: Build the frame out of parts shaped to exactly the right shape and size.
The Mendel frame seems to be a pretty good compromise, combining a few "cut" parts -- the studding (threaded rod) -- and a bunch of "build-up" parts from a previous generation RepRap.
The ideal material for a n+1 generation RepRap has these characteristics:
- raw material extremely low cost
- quick to convert raw material to parts (to reduce generation time) with nth generation RepRap
- adequate strength-to-weight ratio so that it can hold itself up and move the tool head to a precise positions
- ...
- please fill in other characteristics I'm missing ...
The ideal material for a 0th generation RepStraps has these characteristics:
- raw material easily available
- easy for a human to shape ("easy to work") with easily available tools
- adequate strength-to-weight ratio so that it can hold itself up and move the tool head in a precise positions
- ...
- please fill in other characteristics I'm missing ...
Contents
build-up construction materials
The most astonishing thing about RepRap is that it is designed out of parts that, with few exceptions, can be built-up on a RepRep.
- thermoplastic: PLA, ABS, HDPE, LDPE, PP, uPVC -- see Printing Material Suppliers
- molten metal: Fields metal
- cement, modeling clay, pourable epoxy -- PourStrap
modular construction materials
grid beam
grid beam: square beams with a line of holes: typically used for furniture and street signs. "pre-drilled square beams". A typical piece of furniture built out of grid beam uses lots of TriLap joints.
Wooden grid beams seem easier to cut to length. Metal grid beams seem stronger and more rigid.
Does it make any sense to use a mixture of both wooden and metal grid beams bolted together?
- Eiffel is built out of grid beam.
- RBS and Eiffel suggests that a kind of RepRap could make grid beam out of lumber.
- RBS/Beam
- square tube construction techniques
- The square metal tubes with round holes in the side pictured in "Pull Yourself Together, Bot!" look a *lot* like grid beam -- would "real" grid beam work just as well?
- http://www.gridbeamers.com/
- http://gridbeam.biz/
- http://www.alliedtube.com/sign-support/traffic-sign-posts/telespar-square.asp
- http://www.mcmaster.com/#steel-structural-tubing/=49tu63
extruded aluminum
see Extruded Aluminum for similar aluminum materials.
other modular materials
- pegboard: wood sheets with a regular grid drilled into them (RBS/Grid) -- LeCorb; RBS suggests that a kind of RepRap could drill the appropriate grid pattern.
- fischertechnik parts -- Builders/FTIStrap
- LEGO -- Development:Lego RepStrap
- Meccano -- ?
- Merkur -- ?
cut-to-length construction materials
water pipe
- Steel water pipe and fittings -- Builders/Frank; McWire Cartesian Bot 1 2; Builders/PipeStrap; Development:McWire
- PVC water pipe and fittings -- much lighter weight and lower cost and easier to drill than steel; but is it rigid enough?
other cut-to-length construction materials
- low-cost softwood dimensional lumber, roughly 18x45mm and 18x70mm (close enough to "1x2" and "1x4"), bolted together -- WolfStrap
cut-to-shape construction materials
- hardwood cut in more or less the exact same shapes as the plastic parts of a Mendel -- Development:Wooden Mendel
- metal cut in more or less the exact same shapes as the plastic parts of a Mendel -- Development:Metal Mendel
- ??? -- Development:McWire Successor ???
- laser-cut plastic (typically clear acrylic) -- Builders/LaserCut RepStraps; PonokoRepRap
- sheet plywood -- CupCake ??? ; PlywoodRepRaps
- adapting an off-the-shelf milling machine -- Category:MillStrap
- whatever random stuff I had laying around -- Builders/JunkStrap