3D Printer Filament Types and Materials Explained

By Imogen Tasker · Fact-checked by Hugo Lindgren · Published November 14, 2026

PLA starts to soften at about 55-60°C, so a PLA phone mount left on a summer dashboard can droop by the afternoon. Choosing a 3D printer material means matching heat, strength, flexibility and your printer’s hardware to the job the part has to do. This guide compares the common filaments and resins for home FDM and MSLA printing, plus the industrial materials you can order from a print service. It covers datasheet strength figures, prices, drying, fumes, food safety and the 2026 legal rules, and it was last checked on November 14, 2026.

3D printer materials at a glance: the short answer

Most home 3D printing uses thermoplastic filament, and PLA covers most first projects. If a part needs to take more abuse, switch to a different plastic. If it needs finer detail, switch to a different kind of machine.

1. PLA for prototypes, desk gadgets, indoor brackets and anything that stays cool.
2. PETG when the part has to be tougher, flex a little, or survive temperatures up to about 65-70°C.
3. ASA for anything that lives outside or sits behind a windshield.
4. TPU for tires, bumpers, gaskets, phone cases and strain reliefs.
5. Nylon, polycarbonate and carbon-fiber blends for gears, hinges, motor mounts and parts in hot places.
6. Photopolymer resin on an MSLA printer for miniatures, jewelry masters and tiny, detailed parts.
7. SLS nylon or DMLS metal from a print service when a part has to be real metal, or needs strength and shapes a home machine can’t make.

The rest of this guide explains why, and what each material asks of your printer.

Filament, resin or powder: which material your printer can use

Your printer’s technology decides which materials it can use. FDM printers melt plastic filament. SLA, MSLA and DLP printers cure liquid photopolymer resin with light. SLS and MJF machines fuse nylon powder, and DMLS machines melt metal powder. Materials don’t swap between these families.

Process	Material form	How it builds a part	Home use	Main strengths	Main trade-offs
FDM (fused deposition modeling)	1.75 mm filament on a spool	Melts filament in a heated nozzle and lays it down line by line	Very common	Cheap material, big parts, huge material choice	Visible layer lines, weaker between layers
MSLA / SLA / DLP	Liquid photopolymer resin	Light cures thin layers of resin in a vat	Common (MSLA)	Very fine detail, smooth surface	Messy, toxic until cured, often brittle and heat-sensitive
SLS / MJF	Nylon or TPU powder (PA12, PA11)	A laser (SLS) or fusing agent plus heat (MJF) fuses powder; loose powder supports the part	Rare; mostly print services	Strong, support-free functional parts	Expensive machines, powder handling
DMLS / metal powder bed fusion	Metal powder	A laser melts metal powder	Industrial only	Real metal parts	Industrial cost, safety and post-processing

These families also differ chemically. Filaments are thermoplastics: heat softens them and cooling hardens them again, so they can be remelted. That is exactly why a PLA part sags near heat. Cured resin is a thermoset: the light triggers a chemical cross-linking reaction that can’t be reversed. A finished resin print won’t melt back into liquid. It degrades or chars instead, and you can’t regrind failed resin prints into new material.

FDM filament (1.75 mm spools)

FDM printers from Bambu Lab, Prusa, Creality, Elegoo and others push a plastic strand through a hot nozzle. Nearly every current consumer FDM machine takes 1.75 mm filament. Some older or larger machines still use 2.85 mm, so check yours before you order.

Most of the plastic hobbyists buy for 3D printing goes into these machines. The range runs from easy PLA to abrasive carbon-fiber nylon, and that choice is a big reason FDM dominates home workshops. If you plan to print parts for your own machine, the guide on how to build a 3D printable 3D printer shows which of those parts need PETG or ASA rather than PLA.

Resin for MSLA/SLA printers

Resin printers don’t extrude anything. A build plate dips into a vat of liquid photopolymer, and UV light cures one thin layer at a time. MSLA printers shine that light through an LCD mask, DLP printers use a projector, and classic SLA printers use a laser.

Several older articles claim resin is “sent to the extruder to be heated.” That is wrong, and it matters. A resin printer has no nozzle, no hotend and no heated filament path. Its material rules cover curing, washing and skin contact, not melt temperature.

At home, resin printing mostly means MSLA machines from Elegoo, Anycubic and similar brands. Formlabs sells higher-end SLA printers for professional users.

SLS, MJF and metal: materials you can order from a print service

You probably won’t own a powder printer, but you can order its materials. Formlabs’ Fuse series is about the smallest SLS equipment on sale, and it is priced for businesses. Metal processes run in industrial shops with inert gas, powder controls and trained staff. Services such as Protolabs sell parts in these materials to anyone who uploads a file.

Material	Process	Key property (from Protolabs’ material data)	Good maker use
PA12	SLS or MJF	Balanced strength, no support structures needed	Functional enclosures, snap fits, short production runs
PA11	SLS	More ductile: 30% elongation for Protolabs’ PA11 Black, the highest of its listed polymers	Clips, hinges, impact-prone parts
TPU (70A)	SLS	Rubbery: 210% elongation, 4.0 MPa tensile	Gaskets, grips, flexible lattices
316L stainless steel	DMLS	Corrosion resistant and ductile (about 30% elongation)	Wet or outdoor fittings, tough brackets
Ti-6Al-4V titanium	DMLS	High strength for its weight, temperature resistant	Lightweight high-load brackets
AlSi10Mg aluminum	DMLS	Lightweight; parts are stress-relieved after the build	Light housings and frames
Inconel 718	DMLS	Nickel-chromium superalloy for extreme heat and load	Parts near exhaust or other very hot zones

At home, “metal” means metal-filled filament: PLA loaded with metal powder for weight and finish. It is not a structural metal part.

A simple rule of thumb for when outsourcing beats your own printer: order from a service if the part must be metal, if it needs internal channels or lattices that FDM supports would ruin, or if printing it at home would mean buying a new hotend, nozzle, enclosure and dryer for a single job. Keep printing at home while you are still changing the design. Iterating in PLA or PETG costs a few cents per gram and takes hours, not a shipping cycle.

That report draws on more than 1,200 responses from 570 companies. For makers, the takeaway is that much of the industry’s growth comes from paying someone else to print, which is why ordering SLS nylon or titanium online has become routine.

Common 3D printing filaments compared

This table covers the filament types you can actually buy for a home FDM printer. Temperatures are typical ranges. The label on your spool, or the manufacturer’s datasheet, always takes priority.

Material	Nozzle temp (°C)	Bed temp (°C)	Softens around (Tg/HDT)	Enclosure	Hardened nozzle	Needs drying	Difficulty	Best maker use
PLA (incl. PLA+, matte, silk, high-speed)	190-220	50-60	Tg ~55-60°C	No	No	Rarely	Easy	Prototypes, indoor brackets, cases kept cool
PETG	230-250	70-85	Tg ~80-85°C, HDT ~72°C	No	No	Yes	Easy-medium	Functional parts, warm electronics
ABS	230-260	95-110	Tg ~100-105°C	Yes	No	Sometimes	Medium-hard	Indoor heat-tolerant parts
ASA	240-260	90-110	Tg ~98-105°C, HDT ~83°C at 1.8 MPa	Yes	No	Sometimes	Medium	Outdoor housings, car parts
TPU 95A	210-230	30-60	Flexible at room temperature	No	No	Yes	Medium	Tires, bumpers, gaskets
Nylon (PA6, PA12)	250-280	70-100	Grade dependent	Recommended	No (unfilled)	Always	Hard	Gears, hinges, wear parts
PA-CF / PAHT-CF	260-300	80-100	High, grade dependent	Yes	Yes (0.6 mm best)	Always	Hard	Gears, motor mounts, hot brackets
PLA-CF	210-240	50-65	Similar to PLA	No	Yes	Sometimes	Easy-medium	Stiff, lightweight frames
PETG-CF	240-270	70-85	Similar to PETG	No	Yes	Yes	Medium	Robot and drone frames
PC / PC blends	265-300	100-120	Above 110°C for most blends	Yes	No	Yes	Hard	Brackets in hot environments
PC-ABS FR (UL 94 V-0)	240-270	100-110	Vicat ~104°C	Yes	No	Yes	Medium-hard	Electronics enclosures
Polypropylene (PP)	220-250	80-100	Grade dependent	Helpful	No	Rarely	Hard (adhesion)	Living hinges, chemical containers
PVA	190-220	50-60	Low	No	No	Always	Medium	Water-soluble supports
HIPS	230-250	90-110	Similar to ABS	Yes	No	Rarely	Medium	Limonene-soluble ABS supports
Wood-fill	190-220	50-60	Similar to PLA	No	No (0.6 mm helps)	Rarely	Easy	Decorative parts
Metal-fill (PLA base)	195-220	50-60	Similar to PLA	No	Yes	Rarely	Easy-medium	Weighted, metallic-finish décor

Two columns settle most material choices: the softening point and the enclosure. On an open-frame printer, every material marked “Yes” under Enclosure will fight you with warping and cracked layers.

Filament strength and price compared

On manufacturer datasheets, PETG lands around 34-51 MPa in tensile strength and carbon-fiber PET reaches 74 MPa. Every filament gets much weaker when you pull across the layers. Price follows difficulty: in US retail listings this autumn, Bambu Lab PLA and PETG Basic cost about the same per kilogram, while PAHT-CF costs more than twice as much.

Tensile strength and elongation from datasheets

Read the strength figures together with the print orientation. Bambu Lab’s datasheets report X-Y values (pulling along the printed lines) and Z values (pulling across layers) separately, and the gap is large.

Filament (datasheet)	Tensile strength X-Y (MPa)	Tensile strength Z (MPa)	Elongation at break X-Y / Z (%)
Bambu PETG Basic (TDS V3.0)	51	35	9.5 / 5.2
Bambu PETG HF (TDS V1.0)	34	23	8.6 / 5.1
Bambu PET-CF (TDS V3.0)	74	35	4.5 / 2.4
Bambu ASA-CF (TDS V1.0)	34	30	9.6 / 4.4

Prusa Polymers publishes yield values for Prusament rather than break values. Its PETG datasheet lists a tensile yield of about 47 MPa, ASA about 42 MPa and PC Blend about 63 MPa, with elongation at yield of 5.1%, 3.4% and 5.8%. Yield and break figures come from different points on the test curve, so don’t line them up directly against the Bambu numbers.

Three patterns stand out:

• Layers are the weak link. PETG Basic loses about 31% of its strength across layers, and PET-CF loses about 53%. Fibers line up along the extrusion path, so they help along the lines and barely help across them. Orient a part so the main load runs along the layers.
• Speed formulas trade strength for flow. Bambu’s own PETG HF, tuned for high-speed printing, lists about a third less X-Y strength than its PETG Basic.
• Stiff isn’t the same as tough. PET-CF has the highest strength in the table and the lowest elongation. It snaps where PETG would bend.

These are typical values from dry, standardized test bars (ISO 527 or GB/T 1040). Your part’s infill, wall count, layer height and moisture level will move real-world strength more than the brand name does.

Filament price per kilogram

At one US Bambu Lab reseller this autumn, a single 1 kg spool listed at about $23 for PLA Basic (often $19.99 on sale) and the same for PETG Basic. ASA listed at $29.99, PETG HF at $35.99, PC at $39.99, TPU 95A HF at $41.99, and PAHT-CF started at $49.99. Third-party brands, refills without a spool and multi-spool bundles often cost less.

Filament (Bambu Lab, 1 kg)	US retail list price, autumn 2026	Extra hardware you may need
PLA Basic	$22.99 (often $19.99)	None
PETG Basic	$22.99	A dryer helps
ASA	$29.99	Enclosure
PETG HF	$35.99	A dryer helps
PC	$39.99	Enclosure, all-metal hotend
TPU 95A HF	$41.99	Direct drive preferred
PAHT-CF	From $49.99	Hardened nozzle, dryer, enclosure

The value case for beginners is clear. If PETG costs the same as PLA from your brand, any functional part that gets warm or takes impacts should be PETG. Engineering filaments only make sense once you add up the hardware column. A $50 spool of PAHT-CF also means a hardened nozzle, a dryer and an enclosure, and for one part a service-printed nylon piece can come out cheaper.

Everyday filaments: PLA, PETG, ABS and ASA

These four plastics make up most of the filament makers buy. PLA and PETG print well on open printers. ABS and ASA need an enclosure, and they handle heat better in return.

PLA: the default, and why it sags at about 55-60°C

PLA (polylactic acid) is the easiest filament to print. It barely warps and prints at low temperatures on almost any machine. If you don’t have an enclosure, start with it.

PLA’s weakness is heat. Its glass transition temperature sits around 55-60°C, and near that point the part turns rubbery and creeps under load. That is why a PLA dashboard mount bends in summer, and why a PLA bracket clamped near a stepper motor slowly loosens.

PLA is made from plant sugars such as corn starch or sugarcane, which is why it gets called “biodegradable.” That claim needs a big caveat. PLA is industrially compostable: it breaks down in managed facilities that hold roughly 55-70°C with controlled moisture and microbes, the conditions behind the ASTM D6400 standard for compostable plastics. In a backyard compost bin or a landfill it lasts for years. Most industrial composters also don’t accept 3D prints. Treat failed PLA prints as plastic waste, not food scraps.

PLA comes in several variants:

• PLA+ or “tough PLA” adds modifiers for better impact resistance. Formulas vary by brand, so read the datasheet rather than trusting the plus sign.
• Matte PLA hides layer lines well and suits display models and enclosures.
• Silk PLA has a glossy, shimmering finish. It is usually weaker between layers, so keep it for decorative parts.
• High-speed PLA flows better at the fast speeds of current Bambu Lab, Prusa Core One and similar machines.

PLA is stiff and fairly strong in a straight pull, but it is brittle. Snap fits and clips crack sooner than PETG ones.

Is PLA strong enough for robot parts and gears? It handles a light desk robot, a line-follower chassis, or gears turning slowly under small loads. It is the wrong choice for gears driven by geared motors, parts that flex repeatedly, or anything near a warm motor driver. The guide to motors and servos for robotics explains how torque figures turn into the loads your printed parts will see.

PETG: tougher, more heat-tolerant, prone to stringing

PETG is the step up from PLA for functional parts. It is tougher and less brittle, and it handles moisture and many chemicals better. It also prints well without an enclosure.

Its glass transition is around 80-85°C. One vendor datasheet lists a heat deflection temperature of 71.8°C and a Vicat softening point of 79.7°C. In practice, PETG is comfortable up to about 65-70°C under light load.

PETG has two well-known faults. It strings, and it absorbs moisture, which makes the stringing much worse. The drying section below gives the times and temperatures. It also sticks very hard to smooth PEI sheets, so many makers apply glue stick as a release layer to keep the plastic from tearing chunks out of the build surface.

ABS vs ASA: enclosures, fumes, UV

ABS and ASA are chemical cousins with similar strength and similar heat resistance, around 100°C at the glass transition. Both shrink as they cool, so large parts warp and split between layers on an open printer. Both need an enclosure.

Sunlight is the difference. ABS yellows and turns brittle under UV light. ASA replaces ABS’s butadiene rubber with an acrylate rubber and holds up outdoors for years. One vendor lists ASA at a 98°C glass transition (ISO 11357) and an 83°C heat deflection temperature at 1.8 MPa.

ABS still has one advantage: you can smooth it with acetone vapor for a glossy finish, and it is usually a little cheaper. For new projects, ASA beats ABS in almost every case where you would have used ABS. Both give off more fumes than PLA, and the emissions section below explains what that means for where the printer goes.

Which one for an outdoor ESP32 sensor housing

Print an outdoor ESP32 or LoRa sensor housing in ASA. It handles UV, rain and a sun-baked south wall without going brittle. If you don’t have an enclosure, PETG is a reasonable second choice for a node in shade or under a roof overhang.

Factor	PETG	ASA
UV resistance	Fair; slowly degrades and discolors in direct sun	Very good; designed for outdoor use
Heat in direct sun	OK in shade; marginal on hot dark surfaces	Good to about 80°C+ under light load
Printer needs	Open printer fine	Enclosure strongly recommended
Moisture during printing	Must be dry	Less sensitive
Water resistance of part	Good	Good
Best for	Shaded or covered sensors	Fully exposed housings, solar node cases

Flexible and engineering filaments

TPU, nylon, polycarbonate and polypropylene are worth the extra effort when a part has to flex, resist wear or stand up to heat. Each one asks something of your printer: a direct-drive extruder, an enclosure, a dry box or an all-metal hotend.

TPU for robot tires, bumpers and cable strain relief

TPU (thermoplastic polyurethane) is the standard flexible filament. It is graded on the Shore A hardness scale. 95A is the most common and feels firm, like a skateboard wheel. Softer grades such as 85A feel more like a rubber eraser.

TPE is the broader family of thermoplastic elastomers. Spools labeled TPE are usually softer and harder to print than 95A TPU.

Flexible filament buckles when it is pushed through a long tube, so a direct-drive extruder, with the motor right above the hotend, helps a lot. Bowden printers can usually handle 95A at slow speeds. Softer grades generally need direct drive.

Typical maker uses:

• Robot tires printed in TPU and stretched over a PETG or PLA hub.
• Bumpers on a robot chassis to absorb wall impacts.
• Cable strain relief boots where a cable leaves an enclosure.
• Gaskets and feet for enclosures, vibration damping and grip.

TPU absorbs moisture too, and wet TPU strings badly and prints a fuzzy surface.

Nylon and PA-CF for gears and hinges

Nylon (polyamide, PA) is tough, slippery and wear-resistant, which makes it a good fit for gears, hinges, pulleys and bushings. Plain PA6 and PA12 bend before they break, where PLA snaps.

Nylon pulls moisture from the air quickly, and wet nylon pops, bubbles, strings and prints weak parts. Dry it before every session, and ideally feed it from a dry box while it prints.

Carbon-fiber nylons such as PA6-CF and Bambu Lab’s PAHT-CF add stiffness and heat resistance and reduce warping. For PAHT-CF, Bambu Lab recommends a hardened steel nozzle, preferably 0.6 mm (0.4 or 0.8 mm also work), and says stainless steel nozzles are not recommended.

When is nylon worth it? Use it for servo-driven gears, drivetrain parts on a combat or sumo robot, and hinges that cycle thousands of times. For a one-off gear on a slow mechanism, PETG is easier and usually good enough.

Polycarbonate and PC-ABS

Polycarbonate (PC) is one of the strongest and most heat-resistant filaments a home printer can run. Prusament PC Blend lists about 63 MPa tensile yield, and Prusa’s help article recommends a 275 ±10°C nozzle and a 110 ±10°C bed. Many entry-level hotends aren’t built for that.

PC warps hard and needs an enclosure. PC-ABS blends are a little easier to print and still tolerate heat well. Choose PC when a part has to stay rigid near engines, heaters or hot electronics.

Polypropylene: living hinges and chemical resistance

Polypropylene (PP) is light, resists chemicals and survives repeated bending, which makes it the best home material for living hinges, such as a flip-top box lid. It is hard to print because almost nothing sticks to it. Many makers print it on PP packing tape or a dedicated PP build sheet.

Composite and specialty filaments

Composite filaments mix a base plastic with fibers or powders to change its stiffness, weight or look. They are now mainstream: Bambu Lab, Polymaker, Prusa and many others sell PLA-CF, PETG-CF and PA-CF. Most of them need a nozzle upgrade.

Carbon and glass fiber: nozzle wear explained

Carbon and glass fibers are tiny, hard particles that sand away the inside of a brass nozzle. As the bore wears wider, extrusion becomes inconsistent and print quality drops. You won’t see any warning until the parts start to look wrong.

Bambu Lab’s filament guide says carbon- and glass-fiber filaments need a hardened steel nozzle. It strongly recommends 0.6 mm or larger and says to avoid 0.2 mm nozzles. It adds that Bambu’s own PLA-CF and PETG-CF printed with low clog risk on hardened steel nozzles of 0.4 mm or larger. A brass nozzle survives a few prints, then wears out.

Here is what you get for the trouble:

• Stiffness: frames flex less, which helps drones, robot arms and camera mounts.
• Lower weight for the same stiffness.
• Less warping, because the fibers restrain shrinkage.
• A matte, textured finish that hides layer lines.

The trade-off is that CF filaments are often more brittle than their base plastic. Bambu’s PET-CF datasheet shows it: the highest tensile strength in the strength table above, and half the elongation of PETG Basic. Fibers make a part stiffer, not necessarily tougher. Also, don’t run fiber-filled filament through an AMS or other multi-material path unless the maker says it handles abrasive materials.

Flame-retardant filaments for electronics

Flame-retardant filaments are made to stop burning once the flame is removed. They suit enclosures for power supplies, battery packs and anything carrying real current. Spectrum’s PC/ABS FR V0 is one example: a halogen-free filament rated UL 94 V-0, with a Vicat softening point of 104°C. It prints at 240-270°C, and an enclosure is recommended. Bambu Lab sells a PC FR grade as well.

There’s an important catch. UL 94 V-0 describes how standard molded test bars behave at a specified thickness. A printed part has layers, gaps and different wall thicknesses, so the filament’s rating doesn’t automatically carry over to your enclosure. Treat FR filament as a sensible safety margin, not a certification.

Never treat a printed enclosure as an approved housing for mains-voltage circuits. Any mains wiring work needs a qualified electrician. For low-voltage builds, check your wiring with a multimeter continuity test before you close the case, and make sure your soldered joints are solid and insulated.

Wood, metal and decorative fills

Wood-fill, metal-fill, glow-in-the-dark and marble filaments are mostly PLA with additives. They print like PLA but are weaker.

• Wood-fill contains wood fibers and can be sanded and stained. A 0.6 mm nozzle reduces clogs.
• Metal-fill contains copper, bronze or steel powder. It feels heavy, polishes up nicely and is abrasive, so use hardened steel.
• Glow-in-the-dark filament contains strontium aluminate, which is very abrasive. Use hardened steel.
• Conductive and ESD-safe filaments carry carbon black for static-safe trays and simple touch pads. They can’t serve as circuit traces carrying meaningful current.

Support materials: PVA and HIPS

Dissolvable supports let you print overhangs and internal cavities that you could never clean out by hand. They only make sense on a printer that can switch materials mid-print, such as an IDEX machine, a tool changer, or a printer with Bambu Lab’s AMS or Prusa’s MMU.

Support material	Dissolves in	Pairs with	Notes
PVA	Warm water	PLA, some PETG	Very moisture sensitive; store sealed
BVOH	Water (faster than PVA)	PLA, PETG, some nylons	More expensive; dissolves quickly
HIPS	Limonene	ABS, ASA	Prints at ABS temperatures; needs an enclosure
Breakaway support	Snaps off	Matched to the base	No solvent, but leaves rougher surfaces

Resin types for MSLA/SLA printers

Resin printers give up size and toughness to gain detail. Standard resins capture features FDM can’t, but most are brittle, and many have heat deflection temperatures below 60°C. Some industrial SLA resins listed by Protolabs soften at just 47°C, below PLA’s glass transition.

Resin type	Feel/strength	Heat tolerance	Post-processing	Use
Standard	Hard, brittle, crisp detail	Low; often under 60°C	IPA wash, UV cure	Miniatures, display models
ABS-like / tough	Less brittle, some flex before breaking	Low to moderate	IPA wash, UV cure	Snap-fit prototypes, small brackets
Flexible / elastic	Rubbery, varies by Shore rating	Low	Careful wash, cure to spec	Gaskets, grips, soft-touch parts
Water-washable	Similar to standard, often more brittle	Low	Water wash, UV cure	Hobby prints without IPA
Clear	Transparent after polishing or coating	Low	Wash, light cure, clear coat	Light pipes, lenses, display pieces
High-temp	Very stiff, brittle	High (grade dependent)	Wash, extended post-cure	Molds, heat-exposed test parts
Castable / wax-filled	Burns out cleanly	Low	Wash, cure per spec	Jewelry casting masters

Water-washable resin sounds safer than it is, because the rinse water still holds uncured resin. Cure it under UV and dispose of it the way the resin maker says, never down the drain.

These handling rules apply to every resin type:

1. Wear nitrile gloves and safety glasses whenever liquid resin is open.
2. Ventilate the room, because liquid resin gives off VOCs.
3. Wash prints in IPA (or water for water-washable resin) to remove uncured resin.
4. Fully cure prints under UV before you handle them barehanded.
5. Wipe spills right away, and treat paper towels as contaminated until they are cured.

Uncured resin is a skin sensitizer. Repeated contact can cause allergic reactions that get worse each time.

How to choose a 3D printing material for your part

Start from the part’s job, not from the spool on your shelf. Work out its heat, load, flex, environment and finish, then check that your printer can run the material.

The criteria below are weighed in this order: the softening point has to clear the service temperature with a margin, the printer has to run the material without upgrades you don’t own, the part’s flex and wear needs have to match, and cost comes last. A cheap filament that sags still costs you a reprint.

What you need to know before you choose:

• Your printer’s maximum nozzle and bed temperatures.
• Whether it has an enclosure, and whether that enclosure is actively heated.
• Your nozzle material and size (brass vs hardened steel, 0.4 vs 0.6 mm).
• Extruder type (direct drive or Bowden).
• How you’ll dry filament (a dedicated dryer, or a food dehydrator that holds a steady temperature).
• The part’s operating temperature, load and location.

Expected result: a shortlist of one or two materials your printer can handle, plus a test part that has survived real conditions. If the test part sags, cracks or splits along a layer, move one step up the heat or toughness ladder: PLA, then PETG, then ASA, then PC or PA-CF. If it split along a layer, first try reprinting it with the load running along the layers.

Pick a material by project

Project	First choice	Why	Avoid
Raspberry Pi case (warm, active use)	PETG	Handles heat from the SoC and regulator; easy on open printers	PLA in a tightly closed case
Raspberry Pi case (desk, vented, light use)	PLA or matte PLA	Easy, clean finish, cool enough with vents	Silk PLA (weak layers)
Outdoor ESP32 / LoRa sensor housing	ASA	UV and heat resistance	PLA, ABS
Pocket ESP32 node case	PETG or PLA+	Tough, easy, carried indoors and out	Brittle standard resin
Robot chassis	PLA or PETG; PLA-CF for stiffness	Easy, rigid, lightweight	Flexible TPU frames
Servo horns and drive gears	Nylon or PA-CF	Wear resistance and toughness	PLA under high or warm loads
Robot wheels	PETG hub with TPU 95A tire	Rigid hub, grippy tire	Hard plastic tires
Robot bumpers	TPU 95A	Absorbs impacts	PLA (cracks)
Car dashboard or windshield mount	ASA or PC	Survives cabin heat and UV	PLA, and usually PETG
Battery or power enclosure	PC-ABS FR (UL 94 V-0)	Flame-retardant, heat tolerant	Standard PLA
Fit-check prototype	PLA	Fast and cheap	Expensive engineering filaments
Tabletop miniature	Standard resin	Fine detail	FDM for very small scales
Drone or rover frame	PETG-CF or PA-CF	Stiff and lightweight	Silk or decorative PLA
Metal bracket or titanium part	DMLS from a print service	Real metal strength	Metal-fill filament

For a Pi case, plan the cutouts so you can reach the GPIO (general purpose input/output) header without opening the case. The ESP32-S3 kit case in the Meshtastic XIAO case article shows how a small enclosure can stay pocket-sized and still leave the buttons and antenna reachable.

What’s the best material for a Raspberry Pi case that gets warm? PETG, with vents or a fan. A Pi 5 under sustained load heats the air around its processor and power circuitry. In a closed PLA box, those hot spots can creep toward PLA’s softening range.

Heat near electronics: Tg vs HDT in plain language

Tg, the glass transition temperature, is where a plastic goes from glassy and stiff to soft and rubbery. HDT, the heat deflection temperature, is where a standard test bar bends a set amount under a set load. A part under load can sag below its Tg.

Here is what each number tells you:

• Tg comes from a DSC test (ISO 11357). It shows roughly where the material changes character, with or without load.
• HDT comes from a bending test (ISO 75 or ASTM D648) at 0.45 MPa or 1.8 MPa. The 1.8 MPa figure is lower and more conservative.
• Vicat softening point (ISO 306) is the temperature at which a needle sinks 1 mm into the plastic. It usually reads higher than HDT.

Take PETG as a worked example. Its Tg is around 80-85°C, but the datasheet HDT is 71.8°C. If a PETG bracket holds a motor driver board running at 60°C, you have about 12°C of margin before the bracket deforms under load. That’s tight but workable. A PLA bracket in the same spot has almost no margin and will slowly creep.

A good rule of thumb is to keep the continuous service temperature 10-20°C below the HDT. If a datasheet only lists Tg, stay further below it.

Indoor vs outdoor vs in a hot car

The same part needs different plastics in different places.

• Indoors at room temperature: PLA is fine for almost anything that isn’t carrying load near a heat source.
• Indoors near heat (inside a printer enclosure, near motor drivers, LED drivers or regulators): PETG at minimum, ASA or PC for anything hotter.
• Outdoors: see the ESP32 housing comparison above. ASA first, PETG only under cover.
• In a parked car: ASA or PC. A sun-baked dashboard on a summer day gets well past PLA’s softening point, and PETG is marginal.

“My PLA mount warped in the car, what should I have used?” ASA. It survives the heat and the UV coming through the windshield, and it prints well on any enclosed printer.

Keeping filament dry

Most filaments absorb water from the air, and wet filament prints badly. The moisture boils in the nozzle, causing popping, stringing, bubbles and weak layers. Nylon, PVA, TPU and PETG are the most sensitive.

Material	Moisture sensitivity	Drying temp	Drying time	Wet symptoms
PLA	Low-moderate	45-55°C	4-6 h	Brittle filament snaps, slight stringing
PETG	Moderate-high	60-65°C	3-6 h	Popping, heavy stringing, rough surface
ABS / ASA	Moderate	60-80°C	4 h	Bubbles, poor gloss
TPU	High	50-55°C	4-8 h	Stringing, fuzzy surface
Nylon / PA-CF	Very high	70-80°C	8-12 h	Loud popping, foamy lines, weak parts
PC	High	70-80°C	6-8 h	Bubbles, hazy surface, weak layers
PVA	Very high	45-55°C	4-6 h	Gummy filament, clogs

The PETG row comes from Polymaker (about 60°C for roughly 6 hours) and Siraya (65°C for at least 3 hours). The other rows are typical vendor ranges. Go by your spool’s label when it gives figures, and never dry PLA much above its Tg, because the spool and filament can deform.

Why is my PETG stringing and popping so badly? Almost always moisture. Dry it before you change retraction, temperature or travel settings. Tuning settings around wet filament only hides the problem until the next spool.

Do you really need a filament dryer? For PLA in a dry climate, often not. For PETG, TPU, nylon and PC, yes. A dedicated dryer, or a printer with built-in drying, saves more in failed prints than it costs.

Storage matters as much as drying:

1. Keep opened spools in sealed bags or bins with fresh silica gel desiccant.
2. Add a cheap hygrometer card or sensor so you can see the humidity.
3. For nylon and PA-CF, print from a dry box, not an open spool holder.
4. Re-dry any spool that has been open for weeks before an important print.

Common mistakes and troubleshooting by material

Most material problems come down to one of four causes: wet filament, the wrong bed setup, missing hardware, or a part that runs too hot in service.

Problem	Likely cause	Fix
PETG strings and pops	Wet filament	Dry it using the drying table above
ABS/ASA corners lift, layers split	Drafts, no enclosure	Enclose the printer, use a brim, avoid fans
PETG rips the PEI sheet	Too much adhesion	Glue stick as a release layer
CF print quality degrades over weeks	Brass nozzle worn by fibers	Switch to hardened steel
Part snaps cleanly along a layer line	Load pulling across layers	Reorient so load runs along layers; add walls
TPU jams in the extruder	Bowden path, too fast	Slow down, use direct drive, dry the filament
PLA part bends in sun or near a motor	Over Tg	Reprint in PETG, ASA or PC
Nylon prints are foamy and weak	Moisture	Dry 8-12 h, print from a dry box
Resin prints tacky	Under-cured or unwashed	Rewash in fresh IPA, cure longer
Clogs with wood or metal fill	Particles in a small nozzle	Use 0.6 mm; metal fill needs hardened steel

Are 3D printer fumes harmful? PLA vs ABS emissions

FDM printers release ultrafine particles and volatile organic compounds (VOCs) while they print, and research consistently shows ABS emits far more than PLA. NIOSH recommends lower-emitting materials, enclosures with ventilation, keeping your distance and spending less time near the printer.

A 2017 study by UL with Georgia Tech and Emory University identified about 50 VOCs released during FDM printing. The most significant were styrene from ABS, caprolactam from nylon and lactide from PLA. Later work by UL’s Chemical Insights, presented at Indoor Air 2020, found that ABS generally emits vastly more particles than PLA and has higher total VOC emission rates. Because ABS releases so many more particles, the researchers judged its emissions more harmful overall.

Are PLA fumes harmful to human health? PLA is one of the lowest-emitting filaments, but lower doesn’t mean zero. It still releases ultrafine particles and lactide. A ventilated room and some distance from the printer during long jobs make sense even with PLA.

Is it safe to print ABS in your bedroom? Not as a habit. Running ABS or ASA for hours in a closed room where you sleep goes against everything NIOSH advises. Move the printer to a ventilated space, enclose it, and filter or vent the enclosure.

What NIOSH recommends for home and makerspace printers

NIOSH’s guide Approaches to Safe 3D Printing (DHHS NIOSH Publication No. 2024-103) is written for makerspaces, schools, libraries and small businesses. The same controls work at home.

1. Choose lower-emitting materials when the part allows it. PLA instead of ABS is the obvious swap.
2. Use an enclosure with ventilation. NIOSH research found that properly designed local exhaust ventilation with HEPA and carbon filtration reduces airborne particles and chemicals.
3. Prefer printers with built-in filtration that handles both particles (HEPA) and gases (activated carbon).
4. Keep your distance and cut down your time near the printer. Start the print, then leave.
5. Clean work areas to remove settled dust and particles.

Resin brings its own risks: VOCs from the liquid and skin sensitization from contact. Use gloves, glasses and ventilation, and keep resin printers out of living spaces.

Is PETG (or PLA) food safe?

Not as printed. “FDA-compliant PETG” means the raw resin meets a federal food-contact regulation for a described use. It doesn’t mean a 3D-printed cup made from it is safe. Layer lines trap bacteria, and the nozzle and colorants add more uncertainty.

Here is what the label covers. The FDA regulation 21 CFR 177.1630 is titled “Polyethylene phthalate polymers” and sets conditions for using those polymers in food-contact articles. It does not identify PETG generally as the regulated polymer. Colorants fall under a separate regulation, 21 CFR 178.3297. A filament maker can use compliant raw material and still sell a spool that has never been assessed as a finished food-contact product.

Where printed parts fail:

• Layer lines trap bacteria. Biofilms collect in the grooves between printed layers (see the study below).
• Brass nozzles can contain small amounts of lead, which can transfer into the plastic. A stainless steel nozzle avoids that.
• Additives and colorants in a given spool may not be approved for food contact.
• Dishwasher heat can soften PLA and PETG, and many people sanitize items exactly that way.

Size explains why. At a 0.2 mm layer height, the valleys between layers are on the order of 200 µm, while a single bacterial cell is roughly half a micrometer to a micrometer across. A groove hundreds of times wider than the cells gives them shelter that a sponge can’t reach.

Is PETG OK to drink out of? Not as a daily cup. A printed PETG cup has bacteria-trapping grooves you can’t fully clean. If you must, use it for a single cold drink and then throw it away.

Can you make a cup or cookie cutter that’s actually food safe? These are the most reliable routes:

1. Cookie cutters: print in PETG or PLA with a stainless nozzle and treat them as short-lived. Contact is brief, and the dough is baked afterward. Better still, print a cutter that presses into a sheet of food-safe material, or use the print only as a template.
2. Coat the part with an epoxy rated for food contact once fully cured. Follow the epoxy maker’s cure time and limits exactly.
3. Print a mold and cast the final item in food-grade silicone.
4. Buy the cup. For anything you’ll use daily, a molded product is the honest answer.

Avoid resin for food contact unless the resin is specifically certified for it, and then follow its post-processing steps exactly.

What can’t (or shouldn’t) be 3D printed at home, and what’s illegal

Some parts are beyond what home 3D printing plastics can safely do, and a smaller group is illegal to print in parts of the US. Check both lists before you start a project.

Physical limits. Don’t print:

• Pressure-rated parts: air tanks, pressure vessels, hydraulic fittings, compressor parts.
• Load-bearing safety parts: climbing gear, harness buckles, car brake or steering parts, ladder components.
• High-heat parts: anything near engine exhaust, ovens or open flame, or soldering iron holders that touch the tip.
• Certified safety items: helmets, child car seat parts, medical devices, certified PPE.
• Mains-voltage enclosures treated as approved housings. Use listed commercial enclosures, and use a qualified electrician for any mains work.

Printed parts are anisotropic, meaning they are weakest between layers, as the datasheet Z values above show. They can fail suddenly, without the warning a metal part gives when it bends first.

What you can print at home is still a long list: enclosures, jigs, brackets, robot parts, gears, organizers, prototypes, replacement knobs and clips, miniatures and cosplay props. That covers most maker work.

Is it illegal to 3D print a gun? 2026 state laws

It depends on the state, and the rules got much stricter in 2026. Stateline reported in June 2026 that Colorado, Maine, New Jersey, New York, Virginia and Washington all enacted new measures on 3D-printed or unserialized firearms, and some of them now cover the digital files too. Federal law still bans firearms that metal detectors can’t detect, everywhere in the US. The summary below reflects public reporting, not legal advice, so check your state’s current statutes.

State (status as of November 2026)	Measure	What it covers
Colorado	Signed May 2026	Bans 3D printing firearms, unfinished gun parts, large-capacity magazines and rapid-fire devices
Washington	Signed March 2026	Bans 3D printing or CNC milling certain firearms and conversion devices; targets the files
New Jersey	AB 4975	Requires a firearms license to possess digital instructions for printing guns
Maine	LD 1126	Requires serial numbers on privately made firearms, including printed ones
Virginia	Signed April 2026	Prohibits unserialized firearms, including unfinished frames and receivers
New York	Enacted 2026	Tightened rules on 3D-printed and unserialized firearms
California	AB 2047, signed September 26, 2026	From January 1, 2027, requires “firearm blocking technology” on new printers sold once an ASTM standard exists; no retrofit for owned printers

Copyright and trademarks

Downloading a design doesn’t give you the right to sell prints of it. Many models carry non-commercial licenses, and logos and characters are protected by trademark and copyright. Check the license before you sell anything.

Start with one spool and one test part

The fastest way to learn 3D printer materials is to print the same small functional part, such as a bracket, clip or hinge, in PLA and PETG. Print one of each lying flat and one standing upright, then warm them, load them and break them. In an afternoon you’ll see the differences in stiffness, flex, heat tolerance and layer strength that the datasheets describe.

After that, add ASA when you have an enclosure, TPU when you build something that rolls, and a hardened 0.6 mm nozzle before your first carbon-fiber spool. When a part has to be metal, get a quote from a print service before you buy hardware. Pick each new material because a part needs it.

FAQ

What is the most common material used for 3D printing?

PLA is the most common filament for home 3D printing. It prints easily on almost any FDM printer without an enclosure, warps very little and is inexpensive. PETG is the usual second material.

What materials can be 3D printed at home?

Home FDM printers handle PLA, PETG, ABS, ASA, TPU, nylon, polycarbonate, polypropylene, composites such as PLA-CF and PA-CF, and support materials such as PVA and HIPS. Home MSLA printers use photopolymer resins. SLS nylon, MJF and real metal parts such as 316L stainless or Ti-6Al-4V titanium come from industrial machines, usually through a print service.

What is 3D printer filament made of?

Filament is a thermoplastic polymer drawn into a 1.75 mm (or 2.85 mm) strand and wound on a spool. PLA comes from plant sugars such as corn starch, while PETG, ABS, ASA and nylon are petroleum-based. Composite filaments add carbon fiber, glass fiber, wood or metal powder.

Is PLA biodegradable?

Only in industrial composting facilities, which hold PLA at roughly 55-70°C with managed moisture, the conditions behind the ASTM D6400 standard. In home compost or a landfill it barely breaks down for years, and most composters don’t accept 3D prints.

How much does 3D printer filament cost?

At one US Bambu Lab reseller in autumn 2026, 1 kg spools listed at about $20-23 for PLA and PETG Basic, $29.99 for ASA, $39.99 for PC, $41.99 for TPU 95A HF and from $49.99 for PAHT-CF. Third-party brands and refills are often cheaper.

Which filament should you start with if you don’t have an enclosure?

Start with PLA, then add PETG. Both print well on open-frame printers. Leave ABS, ASA, nylon and polycarbonate until you have an enclosure, because they warp and crack in drafts.

Is PETG OK to drink out of?

Not for regular use. Meeting the conditions of 21 CFR 177.1630 applies to the polymer in specified food-contact uses, not to a printed cup. Layer lines trap bacteria, and brass nozzles and colorants add contamination risks.

Are PLA fumes harmful to human health?

PLA emits far fewer particles and VOCs than ABS, according to UL Chemical Insights research. It still releases ultrafine particles and lactide, so print in a ventilated space and don’t sit next to the printer during long jobs.

What things cannot be 3D printed?

Pressure-rated parts, load-bearing safety equipment, high-heat parts and certified safety items shouldn’t be printed at home. Home printers also can’t make real metal parts or food-safe items as printed.

Is anything illegal to 3D print?

Yes, depending on where you live. In 2026, Colorado, Washington, New Jersey, Maine, Virginia and New York restricted 3D-printed firearms, unserialized guns or gun files, and California passed a printer-sales rule that takes effect in 2027. Federal law already bans undetectable firearms.

What is the strongest 3D printer filament?

Among the datasheets compared here, Bambu Lab PET-CF has the highest tensile strength at 74 MPa along the layers, and Prusament PC Blend lists about 63 MPa tensile yield. “Strongest” depends on the load, though. Carbon-fiber blends are stiffest but brittle, nylon is toughest against impact and wear, and PC combines strength with heat resistance. Across layers, every filament is much weaker.

What is the best filament for outdoor use?

ASA is the best common filament for outdoor parts. It resists UV, heat and weather, and its glass transition is around 98-105°C. PETG works in shade but degrades faster in direct sun.

Is ASA better than PETG?

For outdoor and hot-car parts, yes, because ASA handles UV and heat better. PETG is easier to print, needs no enclosure and often costs less. Choose ASA for parts in the sun and PETG for general functional parts indoors.

Do you need a hardened nozzle for carbon fiber PETG?

Yes. Bambu Lab says carbon- and glass-fiber filaments need a hardened steel nozzle, with 0.6 mm or larger recommended and 0.4 mm workable for its PLA-CF and PETG-CF. Brass wears out quickly with these filaments.

Notes on this article

IT

Written by Imogen Tasker

Imogen Tasker covers sensors, breakout modules and workshop tools for Artoo Maker Lab, from temperature and distance sensors to soldering irons and multimeters. She reads manufacturer datasheets, pinout diagrams and library documentation closely, checking voltage levels, interface types and safety guidance so readers can wire parts correctly and choose tools that suit their projects.

Covers: Tools & Workshop, Sensors & Modules

• Fact-checked by Hugo Lindgren against the sources listed below before publication.
• Published November 14, 2026

Fact-checking

• Researched from 8 sources, listed below.
• Every claim is checked by Hugo Lindgren; anything we cannot confirm is corrected, labelled or removed.

Sources (8)

1. Bambu Lab Wiki: Filament guide material table (wiki.bambulab.com)
2. Stateline: More states restrict 3D-printed firearms (stateline.org)
3. NIOSH: Approaches to Safe 3D Printing (Publication 2024-103) (cdc.gov)
4. NIOSH: 3D printing safety feature (cdc.gov)
5. 3DPrint.com: California Signs 3D Printer Gun-Blocking Bill Into Law (3dprint.com)
6. California AB 2047 Explained: 3D Printer Gun Blocking Law (3dprinting.com)
7. TCT Magazine: Wohlers Report 2026 revenues reach $24.2 billion (tctmagazine.com)
8. Metal AM: New Wohlers Report 2026 highlights $24.2B global AM market (metal-am.com)