ABS and PLA are the backbones of the 3D printing world. They’re both easy to obtain and are good enough for most applications. They are not, however, the be-all, end-all filaments for all your 3D printing needs. Depending on your design, you may need something that is much tougher, much more flexible, or simply has a different appearance or texture. Here are a few alternative plastics for your RepRap, Makerbot, or other 3D printer:
Although harder plastics make sense for tools, mechanisms, and objets ‘d’art, there’s always a use for softer materials in designs. One of these filaments is a derivation of PLA going under the names ‘Flex PLA’, or ‘Soft PLA’. This filament is your regular old PLA filament mixed with an unknown chemical to make it soft, tough, and rubbery. It’s an interesting material that [BonziBrian] over on Thingiverse used to print a belt for a RepRap.
It’s not quite up to the challenge of being used for timing belts and the like, but this material’s hardness (Shore D 40, by some accounts) makes it a perfect material for 3D printed robot wheels or tank treads. It’s still a little too hard to print complex negative molds for casting, but if you’re looking for a material for a little bit of give, this is the one.
Wood and Stone
Printing with a wood-like material is nothing new. We’ve seen a few prints made in Laywood (or LAYWOO-D3), and it’s about what you would expect for something that portends to be a 3D printed wooden object. As the material is being printed, the heat from the hot end is able to change the color of the material from a deep, rich mahogany to a light birch. The finished material is supposed to feel something like MDF or the inside of Ikea furniture, but with a little bit of sanding and finishing it should pass for a true wooden object.
If squeezing wood out of a hot end isn’t weird enough, you can now also print in stone. Laybrick is a filament made of very finely ground chalk and a polymer binder that is supposed to feel something like sandstone when printed. After cooling, anything made in Laybrick can be painted, ground, drilled or carved. The best online example of Laybrick appears to be this video of a model stone wall being printed but without an Internet feel-o-vision, it might be necessary to buy a spool of this just to experiment with.
Apart from PLA or ABS, the most popular filament is without a doubt nylon. It’s a much more flexible and stronger material than ABS or PLA, and its self-lubricating qualities lend itself well to gears and other mechanical parts. The very first experiments in printing in nylon originated way back in the early days of the RepRap project with trimmer line designed for a weed whacker. Today things are a bit more refined.
Taulman is most likely the largest alternative filament suppliers on the Internet, featuring two different types of nylon filament for sale. There has been a lot of cool experimentations with Nylon, especially by [RichRap] who used fabric dyes to make tie-dyed objects. Although a few online recommendations suggest using a lot of ventilation when printing with nylon, [taulman] has verified his nylon is exceptionally safe and well below the OSHA limits for exposure to nasty chemicals.
If clear (or translucent, given the number of examples on the Internet) is what you’re going for, you’ll probably want to look into PET. This is the same stuff plastic soda bottles are made of, which coincidentally, makes for a great source for any filament recycling gizmo.
Taulman is also offering a PET-like filament called t-glaze. It’s also somewhere between clear and translucent depending on a printed object’s infill, but this stuff has much better mechanical properties. It prints more accurate and stable parts than ABS, and looks really great to boot.
This last filament isn’t so much of a material, but rather a tool. It’s a water-soluble thermoplastic. What good is this, then?
Although bridging – the ability to connect two parts in a print, effectively printing on air – has gotten very, very good in the last year or so with the right firmware and settings, a few objects are nigh impossible to print without additional support. If you want to print something crazy like a Menger sponge or the GEB cube, using a dual extrusion setup with PVA is the way to go.
One of the better examples of how PVA works is available here; just print your object with PVA as a support, throw it in a glass of water for a few hours, and get a finished object with a bunch of overhangs. There is one downside, though – PVA is incredibly expensive, about twice the price as ABS or PLA filament. That being said, if you need to make something with extreme overhangs, PVA is the way to do it.
3D Printering is a weekly column that digs deep into all things related to 3D Printing. If you have question or ideas for future installments please sending us your thoughts.