Essentials #
- “PLA+” and other modifiers just means “we added some weird stuff we think makes this better”.
- PLA is the easiest filament to print, but weakest against heat and UV.
- Carbon/Glass fiber filaments need hardened nozzles.
- Fiber-filled filaments may reduce warping, but usually weaken layer adhesion.
- Exotic filaments often require an enclosure and high-temp hardware.
Starting Notes #
This is a big article. Use the table of contents to navigate to the section you’re interested in.
Material Statements #
When manufacturers say that their filament is a material (e.g. “PLA”), they’re saying “based on that material”. Every manufacturer adds their own concoction of additives (plasticizers, dyes, etc.) to make it their own. This means that things that are true of one brand’s PLA might not be true of another brand’s PLA.
Fiber-filled materials #
“CF/GF” means the manufacturer has added Carbon Fiber or Glass Fiber to the base material.
Fibers are added to increase the ease of printing (it makes warping less likely), to improve a desired property of the material (e.g heat deflection temperature, electrical conductivity, etc.), or to change the finish of the material (that matte looks great).
The tradeoff is it makes the material more expensive and often makes layer adhesion worse.
There are some concerns about the safety of CF/GF materials; both inhalation risks while printing and risks from handling printed parts.
Ask three different people how risky they think it is and you’ll get three different answers. Make your own decisions based on your risk tolerance.
Filament Materials #
PLA #
The quintessential 3D Printing filament. Comes in a rainbow of types and colors. Useful for lots of things. Everybody makes this, and you can find almost every color, finish, and level of sparkle you might want.
Very forgiving to print, low warp, and sticks to most surfaces without trouble.
Useful for lots of decorative and functional things, but doesn’t excel at heat, constant force (it creeps and deforms), UV exposure, or chemical resistance.
People are often misled by the marketing for PLA-CF.
PLA-CF should be primarily be thought of as an aesthetic material, imo, and is only an improvement over regular PLA in very specific uses. It’s more brittle than regular PLA, and has worse layer adhesion than regular PLA.
PETG #
A little more resilient and a little more heat tolerant than PLA. Also a little more chemical resistant than PLA. More hygroscopic (absorbs moisture) than PLA.
Can be stringy and tends to bond aggressively to PEI build plates.
ABS/ASA #
Much more heat and chemical resistant. Most of the plastic in your car is ABS; it can hold up to much more abuse than PLA and PETG. ASA is more uv-tolerant than ABS. Both release carcinogens when printing. Safest handling is to exhaust your printer air directly outside.
Both like to warp and are easier to print in enclosed printers.
TPU #
Flexible filament. Good for parts that need to bend or flex. Also has excellent layer adhesion. Very good chemical tolerance. Basically indestructible when well-printed. Can require some special handling to print well. Extremely hygroscopic (absorbs moisture); a couple hours in room air can be enough to cause problems.
Comes in a variety of hardnesses. Foaming TPUs are available that are softer and more flexible.
PEBA #
Flexible filament with better rebound than TPU. If you want to print bouncy things, this is a good choice. Extremely hygroscopic (absorbs moisture); a couple hours in room air can be enough to cause problems. Can require special handling to print well, like TPU. Tricky to tune.
Exotics (Nylons/PAs, PP, PC, PPS, etc.) #
These are specialty filaments that trade ease of printing for extreme material properties. They’re usually more expensive, harder to print, and very hygroscopic (they’ll suck up moisture from the air quickly and need constant drying). Many require hardened nozzles, high nozzle temperatures, heated chambers, and an enclosed printer to use them successfully.
Nylons (PA6, PA12, blends) #
Very tough, abrasion-resistant, and slippery. Excellent for gears, bushings, and parts that see repeated stress. Downsides: they warp easily, absorb lots of moisture, and can be difficult to keep dimensionally stable.
Polypropylene (PP) #
Lightweight, fatigue-resistant (great for living hinges). Naturally flexible and chemical-resistant. Very poor bed adhesion, requires special build surfaces.
Polycarbonate (PC) #
High impact strength and heat tolerance. Transparent grades exist. Great for functional and structural parts. Needs high temps, enclosure, and constant drying. Brittle if moisture-laden.
PPS / PPSU #
High-end engineering plastics. Extremely strong, chemically resistant, and stable at very high temperatures. Often used in aerospace or medical. Very difficult to print on most printers.
PVA #
Water-soluble filament. Useful for printing support structures for detailed geometry, or inside geometries where normal support structures can’t be removed. Incredibly hygroscopic (absorbs moisture quickly), so you need to dry it very well, and it must be kept dry while printing.
mecha on the Bambu Forums has a very nice guide to printing PVA on an H2D printer on the Bambu Forums.