notes/notes/3D printing/Filament.md

https://www.youtube.com/watch?v=weeG9yOp3i4

PLA (Polylactic acid)

Pros	Cons
- Easy to print - Very cheap - Widely available - Prints quickly - Prints well - Stiffest non-composite thermoplastic	- Can permanently deform with consistent load application - Not UV resistant - Warps under heat - Shatters - Difficult to sand/glue/paint

Variants

Silk PLA

Silk PLA has an additive to make prints shinier. This weakens the print, but it makes supports easier to remove. When silk PLA heats up, it puffs up and this can damage the extruder.

Silk PLA trades performance for aesthetics and can damage both a Bambu AMS and a Prusa MMU.

PLA-CF (Carbon Fiber PLA)

Carbon fiber PLA is made by adding chopped or ground PLA to the filament. It does not typically improve the strength of prints, but it stabilizes the filament as it cools (preventing warping and shrinkage), and it can improve detail.

The addition of carbon fiber makes the end product stiffer, but more brittle. PLA-CF is one of the best filaments for detail oriented printing. It's overall a better filament than PLA, with the only drawbacks being a hardened steel nozzle requirement, and lack of color options.

Metal-filled PLA

Metal filled PLA is made by adding metal shavings to the filament during production. This makes the print heavier and infuses the print with some of the properties of the metal added. Copper infused filament can gain a patina, stainless steel infused filament can be polished, iron is magnetic, et cetera et cetera.

The addition of metal particulate reduces the strength of the print and makes it more brittle. Metal-filled PLA is extremely expensive, difficult to print with, and anything that can be achieved with metal-filled PLA can also be achieved using paint, inserts, or some form of electroplating.

Wood-filled PLA

Wood-filled PLA is comprised of sawdust, and PLA. Cheap wood-filled PLA looks brown and has no particular wood-like qualities, but higher quality WF-PLA has visible chips of wood. This impacts the print by giving it a wood-like texture and allowing you to use varnish on the print.

WF-PLA is difficult to print with, it easily absorbs humidity and sputters from the nozzle. The resulting product is also weaker.

PLA Alloys

This category of PLA is created by combining PLA with another plastic additive to change the properties of the resulting filament in some way.

There are 3 primary categories of PLA alloys:

1. "Tough" PLA Tough PLA is created by combining PLA with polybutylene terephthalate, or PBT. PBT is commonly used in keycaps for keyboards.

Tough PLA prints and acts similarly to PLA, but it has higher temp and impact resistance, and it's less brittle. This is largely an upgrade to PLA with no real drawbacks.

2. "Matte" PLA Matte PLA is created by combining PLA with a plant based additive.

Matte PLA has a higher impact and shatter resistance than regular PLA, but it absorbs humidity more easily and is more likely to jam in an extruder during printing. This is largely a side-grade to regular PLA, it makes a slightly different set of tradeoffs. 3. "High speed" PLA High speed PLA has a lower melting temperature and a reduced viscosity, greatly increasing the speed at which it can be printed at.

PCL (Polycaprolactone)

PCL has an extremely low melting point, printing at just 100 Celsius. The melting point is so low that you can shape it in a warm bath, or with a hair dryer.

It has a warm waxy consistency that no adhesive will stick to.

PETG/PET-G (Polyethylene terephthalate-glycol)

Pros	Cons
- Tougher - Better temperature resistance - Highly transparent - Very low coefficient of friction. - Food safe	- Slightly more difficult to print than PLA - Struggles with overhangs - Struggles with support removal - High humidity absorption

Variants

PETG-CF (Carbon Fiber PETG)

Carbon fiber stabilizes molten filament, and given that PETG struggles with overhangs, PETG-CF has massively improved print support quality, along with improved stiffness.

The combination of matte carbon fiber with shiny polyester tends to create a very unique, aesthetically pleasing finish.

PCTG (Polycyclohexylenedimethylene Pthalate-Glycol)

PCTG is a newer, better, alternative to PETG, compared to PETG:

Pros	Cons
- Higher toughness - Lower water retension - Very little warping or sagging - Almost perfect layer adhesion	- Supports are difficult to remove - Expensive - Not widely available

PET (Polyethylene Terephthalate)

PET is the foundation of PET-G, but without the addition of glycol as a plasticizer. Compared to PETG:

Pros	Cons
- Stiffer - Tougher - Shinier - Very high temp resistance - Easier to print than other engineering filaments like nylon or polycarbonate	- Extremely high print temp (275C minimum) - Struggles with humidity, overhangs, and warping

Variants

PET-CF (Carbon Fiber PET)

• Almost as easy to print as PETG
• Extremely stiff
• Hard to find, expensive

PVB (Polyvinyl Butyrate)

• Printing qualities similar to PLA
• Behaves similar to PETG, weaker but more flexible
• When exposed to isopropanol alcohol, the layers melt and fuse together, resulting in a very glossy, seamless finish.

ABS (Acrylonitrile Butadiene Styrene)

• Very common in consumer injection-molded parts.

Pros	Cons
- Melts in acetone, acetone vapor smoothing can be used to improve surface finish - Prints fairly quickly - Very high toughness relative to PLA or PETG - High temperature resistance - UV resistant	- Very high warpage - Smells horrid and outputs toxic fumes when printing

ASA (Acrylonitrile Styrene Acrylate)

Chemically similar to ABS, just better.

Pros	Cons
- Very high temp resistance (past 100C) - Very high UV resistance - Matte surface finish - Prints very quickly - Greatly reduced warping compared to ABS	- Equally bad fumes as ABS - Still somewhat difficult to print.

HIPS (High Impact Polystyrene)

Similar to ABS, but softer, waxier, and more flexible.

Has a very low density, works well for wearables and props. HIPS is commonly used as a support material for ASA or ABS because limonene will dissolve HIPS but does not impact other plastics in the styrene family (ABS, ASA).

Nylon

Nylon filaments are engineering filaments. They're difficult to print but have excellent mechanical properties.

Variants

PA-6

Pros	Cons
- Extremely strong - Excellent layer bonds - High flexibility - Very high temp resistance - Very low coefficient of friction	- Horrible to print - Very high moisture retention - Can't be too dry - Very high warpage - Requires a closed (ideally heated) chamber

PA-12

• Higher warpage than PA-6
• Higher toughness
• Higher temp resistance
• Durable but brittle

PA-CF (Carbon Fiber Nylon)

• Very stiff
• Less warping
• High friction
• High end printer required

PA-GF (Glass Filled Nylon)

• Used in the real world (handguns, chainsaws)
• More affordable than PA-CF
• Much stiffer, tougher, and more resistant to heat and abrasion than vanilla nylon.
• Greatly reduced warping
• Fairly easy to print
• Still requires a high-end printer (tungsten carbide or gemstone nozzle, abrasion resistant drive gears)
• Durable enough to act as a viable alternative to machined aluminum

PA-PETG (Nylon PET alloy)

Often called tough PETG or low temp nylon, PA-PETG is meant to serve as both a step up from PETG and a more accessible nylon alternative.

• Bad warping, poor bed adhesion
• Often just better to use nylon or PETG

Polycarbonate (PC)

• In the real world, polycarbonate is used to make bulletproof glass. While FDM polycarbonate is not bulletproof, many of the properties of polycarbonate still apply.

Pros	Cons
- One of the toughest, stiffest filaments - Extremely high temp resistance - Does not shatter - Highly transparent	- Extremely high moisture retention - Prints above 300C - Difficult to print

Variants

PC-CF (Carbon Fiber Polycarbonate)

• Record setting stiffness, prints can withstand hundreds of kilos
• Will destroy most drive motors
• Surprisingly cheap (~60USD/kilo at the time of writing)

PC-PBT (PBT Infused Polycarbonate)

PBT flaccifies the polycarbonate but preserves PC's strength and shatter resistance in the cold, making it one of the few cold-resistant filaments.

• Lower print temp
• Improved print quality
• Very low warping
• One of the easiest filaments to print in

PMMA (Polymethylmethacrylate)

Also known as acrylic plexiglass, the high transparency of PMMA is the only advantage it has over other polycarbonates for printing.

Pros	Cons
- Highest transparency thermoplastic - Can be buffed to a frosted/polished surface - High UV resistance - Relatively affordable	- Horrible bed adhesion - Bad layer adhesion - High coefficient of thermal expansion leads to constant print failures during or after the printing process - Very brittle - High water absorption

TPU (Thermoplastic Polyurethane)

TPU is the most common flexible filament

Pros	Cons
- Flexibility - Cheap - Wide range of colors and hardnesses - Perfect layer adhesion - Basically shatterproof	- Permanently bonds to most build plates (use gluestick) - Very high water absorption, needs to be dry to print well

Variants

TPU (~99D)

• Harder than a skateboard wheel
• Basically rigid
• Useful because it's "shatterproof"
• Often used for combat gear or robotic applications
• Easiest TPU variant to print

TPU (~80D)

• About as hard as the sole of a running shoe
• Good for things like bumpers or hinges
• Still fairly easy to print

TPU (~80A)

• Very soft
• Prints at very low speed, can wrap itself around the drive gears

TPE (Thermoplastic Elastomer)

Pros	Cons
- Flexible - Stretchy	- Very difficult to print with

SEBS (Styrene Ethylene Butterine Styrene)

TPE enhanced with the same chemicals used to make ABS.

Pros	Cons
- Prints much better than TPE - Very flexible and tough	- Very hygroscopic - Styrene fumes released during printing - Softens at a very low temp - Still requires some level of tuning

PP (Polypropylene)

• Very bendable
• Very rugged
• Perfect layer adhesion
• Very low density
• Horrible bed adhesion
• High warping
• Supports are impossible to remove

Variants

PP-GF (Glass-filled PP)

• Standard for industrial machinery
• More difficult to print than regular PP
• One of the toughest, most durable filaments
• Very lightweight

OBC (Olefin Block Copolymer)

• Fairly new for 3D printing
• Attempts to combine the good qualities of PP and PET-G
• Very low bed adhesion
• Very expensive
• Typically requires printing on a purpose made printer

HDPE (High Density Polyethylene)

• Most bottles and jugs use this filament
• Horrible to print in every way
• Useful for purging the nozzle when switching between high and low temp filaments

POM (Polyoxylmetn)