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The handbook for everything you set before you press print.

9 sections: the machine, the material, the slicer, the fits and the failures. Every number here is a starting point to calibrate from rather than a measurement — the measured properties live in the spec table, each with its standard.

A print setting is not a measurement. No set of values is right for every machine: the same spool wants two different profiles on two different printers. Use this page to learn what each setting does and where to start, then calibrate against your own test print.

01 / 9 sections

Four technologies, and the machine in front of you

No setting rescues the wrong technology. Each of these is good at a different job, and they are two orders of magnitude apart in cost — so this is the first decision, ahead of choosing a material.

Four 3D printing technologies compared
TechnologyHow it buildsWhat it tradesWhat it is for
FDM / FFFExtrudes molten filament through a nozzle, one layer stacked on the last.Visible layer lines, and Z strength around half of XY.Jigs, load-bearing parts, enclosures, functional prototypes, large parts.
Resin (SLA / LCD / DLP)UV cures liquid resin layer by layer, by laser or LCD panel.Needs washing and curing; uncured resin is a skin sensitiser; parts are more brittle.Detailed figures and models, dental, castable jewellery, small parts needing a fine surface.
SLSA laser sinters nylon powder; the unsintered powder is the support.Expensive machines and powder, a grainy surface, and almost always a service bureau job.Complex hollow parts, printed-in-place assemblies, small runs needing near-isotropic strength.
DMLS / SLMA high-power laser fuses metal powder into solid material.The most expensive, and needs heat treatment and machining after printing.Real metal parts: conformally cooled tooling, aerospace brackets, medical implants.

Frame and motion system

i3 (the bed moves in Y), CoreXY (the head moves inside a box) or Delta. CoreXY runs faster at the same quality because less mass moves, and the box shape holds heat for ABS and ASA.

Extruder: direct drive or Bowden

Direct drive puts the motor on the head — required if you print TPU. Bowden pushes filament down a PTFE tube: a lighter head that moves faster, but retraction is less decisive and stringing is likelier.

Hot end and nozzle

Sets your maximum temperature and maximum flow. Only an all-metal hot end goes past 250 °C; carbon- and glass-filled materials require a hardened nozzle, since brass wears open within a few hundred hours.

Build plate

Spring steel with textured or smooth PEI, carborundum glass, or a sheet. Most adhesion failures are not the surface's fault — they are the finger grease on it.

Electronics and levelling

A 32-bit board, quiet drivers, an auto-levelling probe and a runout sensor. Auto-levelling only compensates for a warped surface — it does not replace getting Z-offset right.

02 / 9 sections

Temperature, chamber and drying

No slicer setting compensates for a wet spool. In hygroscopic filament the absorbed water boils at the nozzle, and you get a pitted surface, an audible crackle, and a part well below the number on the data sheet.

Temperature and drying by grade
GradeNozzleBedChamberDrying
PLA Matte205–220 °C55–65 °CNot required45 °C / 4 h
PLA High Speed215–235 °C55–65 °CNot required45 °C / 4 h
PLA-CF215–230 °C55–65 °CNot required50 °C / 6 h
PETG Core235–250 °C75–85 °COptional65 °C / 6 h
PETG-CF240–260 °C75–85 °COptional70 °C / 8 h
ABS Core245–265 °C95–110 °C45–55 °C70 °C / 4 h
ASA Core250–270 °C100–110 °C50–60 °C70 °C / 4 h
TPU 95A220–235 °C40–60 °CNot required60 °C / 6 h
TPU 85A215–230 °C35–50 °CNot required55 °C / 6 h
PA-CF260–290 °C80–100 °C50 °C70 °C / 8 h
PA12250–275 °C70–90 °C45 °C70 °C / 12 h
PA6-GF270–300 °C90–110 °C55 °C80 °C / 12 h
PC Core265–300 °C100–120 °C50–60 °C80 °C / 8 h
PC Blend250–275 °C95–110 °C45–55 °C75 °C / 6 h

Print settings are the common starting window for this material class, not measurements. Calibrate with a temperature tower and a flow test on your own machine.

This table is built from the site's own material catalogue, so it cannot drift from the family pages. The measured properties — tensile, HDT, impact — are in the full spec table, each with its standard and its source.

Signs the spool is wet

Popping or hissing at the nozzle, bubbles in the extrusion as it comes out, a duller and rougher surface than usual, noticeably more stringing with no setting changed, and filament that snaps dry instead of bending.

Drying is not warming

Drying means long enough at the right temperature below the material's softening point: two hours at a low setting does not pull moisture out of the middle of a spool. Too hot and the wraps fuse to each other and the spool is scrap.

For nylon and PA-CF, drying is not enough

Nylon takes on meaningful moisture within hours of sitting in open air, so it has to be fed from a heated dry box for the whole print, not merely dried before it.

What an enclosure does

An enclosure holds the air around the part at a steady temperature, so the layers shrink by the same amount. That is what stops ABS, ASA and nylon warping and delaminating. For PLA it works the other way: too warm a chamber softens it and costs detail.

Read further:How to dry filament properly (and know when it's wet)PLA vs PETG vs ABS: choose by the job, not the hypeHow to read a filament data sheet without being fooled

03 / 9 sections

Diameter, layer height and speed

These three set your print time and most of your surface quality, and they constrain each other: layer height is capped by nozzle diameter, and speed is capped by the flow your hot end can actually melt.

Choosing a nozzle diameter
DiameterUsable layer heightWhat it tradesUse it when
0,2 mm0,05 – 0,15 mmSlowest, and the likeliest to clog.Miniatures, raised lettering, small-scale models.
0,4 mm0,08 – 0,30 mmTrades nothing much.Almost everything. This is the nozzle every shipped profile is tuned around.
0,6 mm0,12 – 0,45 mmLoses fine detail and small text.Mechanical parts, filled materials, and when you want stronger layer bonding.
0,8 – 1,0 mm0,20 – 0,75 mmA visibly coarse surface, and it needs a high-flow hot end to keep up.Large parts, blanks to be machined back, furniture-scale work.

Rule of thumb: keep layer height at or under 75 % of nozzle diameter. Above that the new layer does not press into the last one, and the part delaminates under load.

Layer height: surface traded against time
Layer heightSurfaceRelative print time
0,08 mmLayer lines barely visible≈ 2,5×
0,12 mmPresentation quality≈ 1,7×
0,16 mmGood≈ 1,25×
0,20 mmDefault, fine for most work
0,28 mmLayer lines clearly visible≈ 0,7×

These ratios are against 0.20 mm on the same model, not absolute times — the more horizontal detail a model has, the more they compress. On curved surfaces, adaptive layer height buys far more than dropping the layer height of the whole model.

Starting speed window by extrusion role (mm/s)
Extrusion rolePLAPETGABS / ASATPU
Initial layer20 – 3020 – 3020 – 3015 – 20
Outer wall20 – 4020 – 4020 – 4015 – 25
Inner wall40 – 6040 – 6040 – 6020 – 35
Sparse infill150 – 250150 – 200150 – 20040 – 80
Bridge20 – 6020 – 5020 – 4015 – 25
Travel500 – 1000500 – 800400 – 700150 – 250

The outer wall is the only extrusion anyone sees, so it is the one worth running slowest and the last one to speed up. Inner walls and infill are the opposite: nobody sees them, and they are where the time goes.

Source: Parameters selection and setting during slicing Bambu Lab · 28/08/2026

Acceleration

A speed setting is only reached if the move is long enough to accelerate into it. On a model full of small detail, acceleration decides print time more than speed does. Shipped profiles set it low for the initial layer and the outer wall and high for travel — which is why the first layer sticks and the outer wall does not ring.

Slow down for overhangs

The machine slows where an extrusion reaches out past what is under it, by overlap threshold. Leaving it on is almost always worth it: it slows only the moves that would look bad fast.

Inner wall set to 0

In many profiles an inner-wall acceleration of 0 means “use the normal printing value”. That is not a misconfiguration.

Source: Bambu Studio Print Settings — slicing parameter documentation Bambu Lab · 28/08/2026Documentation for one slicer, not for a material. Parameter names and their shipped defaults change between Bambu Studio versions and between machine and nozzle profiles. Check against the profile installed on your own machine.

Read further:The print settings that actually change part strength

04 / 9 sections

Strength lives in the walls, not the infill

The least intuitive thing in this handbook: when a part breaks, adding wall loops beats adding infill density almost every time, for the same material and less time. The walls carry the bending moment; the infill only stops the two shells collapsing into each other.

Wall loops

How many perimeters ring each layer. Two is the default; three or four for a load-bearing part. Per extra gram of material, this is the highest-yield strength setting there is.

Alternate extra wall

Adds an extra perimeter on alternating layers, offset from the one below. The layers interlock instead of stacking straight, which reduces delamination on thin, tall walls.

Embedding the wall into the infill

Pushes the wall a little way into the infill region. It bonds shell to core, so the shell is less likely to peel off the core under load.

Detect thin wall

Handles regions narrower than one extrusion, which would otherwise be left empty. Worth turning on for small parts and lettering.

Source: Bambu Studio Print Settings — slicing parameter documentation Bambu Lab · 28/08/2026Documentation for one slicer, not for a material. Parameter names and their shipped defaults change between Bambu Studio versions and between machine and nozzle profiles. Check against the profile installed on your own machine.

Wall generator: Classic or Arachne

Classic prints every perimeter at one width, so at sharp corners and small features it leaves gaps no whole extrusion fits into. Arachne varies extrusion width to the local geometry and fills them. On models with fine detail or unevenly thin walls it is visibly cleaner — which is why current slicers default to it.

Source: Introduction to wall generator — Classic and Arachne Bambu Lab · 28/08/2026

Top shell, bottom shell and infill — starting window
SettingWhat it controlsStarting point
Top shell layersSolid layers on the top face.4 – 6
Bottom shell layersSolid layers on the face against the plate.3 – 5
Top / bottom shell thicknessA floor in millimetres that overrides the layer count at fine layer heights.0,8 – 1,2 mm
Sparse infill densityDensity of the internal lattice.15 – 25 % general · 35 – 60 % load-bearing · 5 – 10 % decorative
Infill / wall overlapHow far infill laps onto the wall.10 – 20 %
Infill directionAngle of the lattice against X.45° — distributes load more evenly than 0°/90°
Sparse infill anchorHow far infill runs along the wall before turning inward.400 % of extrusion width, capped at 10 – 20 mm

Starting points to calibrate from, not measurements. Your machine, nozzle, spool and model will each move them a few per cent — print a test coupon before you print the real thing.

Infill patterns
PatternCarries load inWhat it tradesUse it for
GridTwo directions, in the layer planeThe nozzle crosses its own extrusion at every intersection.General printing, the safe default
GyroidAll directions, near-equallyLonger toolpaths, so slower to slice.Parts loaded from several directions; runs smoothly at speed as it never self-intersects
CubicThree dimensionsMore material than Grid at the same density.Engineering parts under compression and bending
Tri-hexagonThree in-plane directionsLittle benefit in Z.In-plane stiffness on a material budget
HoneycombIn-plane, high stiffness per gramSlower than the rectilinear patterns.Large flat plates, panels, light shells
LightningEffectively nothingBuilds only what holds the top surface up.Decorative models, drafts, statues
ConcentricAlong the part outlineWeak against loads across the rings.Flexible parts (TPU), curved faces needing even support

There is no best infill pattern, only one that matches how your part is loaded. If you do not know where the load comes from, Gyroid is the least regrettable choice.

Source: Infill patterns Prusa Research · 28/08/2026PrusaSlicer's own description of its infill patterns. The pattern names are shared across slicers; the toolpaths they generate and the material they consume are not necessarily the same.

Read further:The print settings that actually change part strength

05 / 9 sections

Support that holds and still comes off

Good support is support you pull off by hand without scarring the part. Both of those live in exactly three clearance numbers; everything else is refinement.

Support settings — starting window
SettingWhat it controlsStarting point
Top Z distanceVertical gap between the top of the support and the underside of the model. The single most important number here.0.12 – 0.20 mm (exactly one layer)
Bottom Z distanceThe gap where support stands on a surface of the model itself.0,16 – 0,20 mm
Support / object XY distanceHorizontal clearance to vertical walls. Too small and the support welds itself to the side of the part.0,30 – 0,40 mm
Top interface layersDense layers directly under the model that form a flat bearing surface.2 – 4 layers (3 is usual)
Top interface spacingLine spacing within the interface layer.0,25 – 0,30 mm
Initial layer densityDensity of the support's footprint on the plate.80 – 100 %
Initial layer expansionWidens the footprint so tall supports do not topple.2 – 5 mm
Base pattern spacingLattice spacing in the support body.2 – 3 mm

Starting points to calibrate from, not measurements. Your machine, nozzle, spool and model will each move them a few per cent — print a test coupon before you print the real thing.

Source: Support settings Bambu Lab · 28/08/2026

Support styles
StyleStructureWhat it tradesSuits
Tree / OrganicBranching trunks that touch the model only at the tips.Slower, and it will not hold up a large heavy flat area.Statues, character models, organic shapes, tight gaps
NormalA vertical lattice straight up from the plate.The most material, and the most marks left behind.Wide flat overhangs, and parts that are heavy while printing
SnugBuilt only under what needs it, hugging the outline.Not for areas carrying real weight.Everyday printing at moderate complexity
Support interface (enabled separately)A dense layer inserted between support and model.Harder to remove, and slower.When the underside is a surface someone will look at

This is a fit table, not a ranking: the right style depends on the shape and on which face has to look good. Before printing, step through the layer preview — every support mistake is visible there, for free.

06 / 9 sections

The seam, and the numbers that fix dimensions

Every layer has to start and finish somewhere, and the vertical scar down the side of a part is where. You cannot remove it, but you can hide it and flatten it. In the same group live the compensation settings — the ones that decide whether a printed hole takes the screw.

Seam position

Aligned stacks every seam into one vertical line — conspicuous, but easy to hide, since you only have to turn that line to the back. Random scatters them: no long scar, but speckling everywhere. For a part with a front, Aligned almost always wins.

Smart scarf seam

Overlaps the start and end of the loop on a slope instead of stopping dead, so there is no blob at the end point. It is the largest single improvement to seams in recent years, and worth enabling on anything that has to look good.

Scarf steps and angle threshold

How many flow steps the ramp is divided into: more steps, smoother, marginally slower. The angle threshold decides whether the scarf is applied at sharp corners — the sharper the corner, the better it is left alone.

Seam away from overhangs

Moves the seam off overhanging edges. A seam on the lip of an overhang is the worst place for one, because the extrusion there already has nothing under it.

Source: Seam settings Bambu Lab · 28/08/2026

Dimensional compensation and surface finishing
SettingWhat it fixesStarting point
Elephant foot compensationThe bulge at the bottom layer from being squashed onto the plate — it stops a part sitting flat or fitting flush.0,05 – 0,15 mm
X-Y hole compensationPrinted holes come out undersized, because the extrusion pulls inward around the curve.+0.10 – 0.30 mm on diameter (see the tolerance table)
X-Y contour compensationOverall size error on the outside profile.0 mm, until you measure a systematic error
Resolution / arc fittingCurves broken into straight segments you can see as facets.0.012 mm, with arc fitting on
IroningVisible extrusion lines on the flat top face.Top surfaces only; adds 10 – 40 % to print time

The first three should only be touched after you have measured a test coupon with calipers. Adjusting them by feel is the fastest way to turn a small error into a large one in the other direction.

Source: Bambu Studio Print Settings — slicing parameter documentation Bambu Lab · 28/08/2026Documentation for one slicer, not for a material. Parameter names and their shipped defaults change between Bambu Studio versions and between machine and nozzle profiles. Check against the profile installed on your own machine.

07 / 9 sections

Clearance for parts that go together

An FDM machine does not print the size you drew, and its error is systematic: holes shrink, shafts grow, bottoms bulge. This table is the clearance to add in CAD so two parts go together — not a machining tolerance, but the place to start a test coupon.

Starting clearance by type of fit
Type of fitStarting clearanceUse it forDesign note
Press fit0,05 – 0,15 mmGears pressed onto a shaft, locating pins, fixed couplings.Chamfer the shaft 0.5 mm so it self-centres. Start at the small end and open up.
Sliding fit0.15 – 0.30 mm (0.20 mm is a good place to start)Hinges, slides, bushings, anything that moves.Print the sliding face around the Z axis, where it is roundest.
Snap fit0,20 – 0,40 mmBox lids, enclosure catches, battery covers.Use PETG or ABS. PLA is stiff enough but brittle — the catch snaps off rather than springing back.
Threads0.10 – 0.20 mm radialPrinted bolts and nuts, screw caps, pipe couplings.Small values for small threads. A thread with flanks at 45° or steeper prints without support.
Hole compensationAdd 0.10 – 0.30 mm to the diameterM3/M4/M5 clearance holes, heat-set insert bores, dowel holes.The smaller the hole, the larger the relative error. Compensate in CAD or with X-Y hole compensation — not both.

This is trade convention, not a value measured to a standard. The right clearance depends on the machine, the material and the day's humidity: PLA holds size more closely than ABS and ASA, which shrink as they cool. The cheapest way to find yours is a test bar with five holes 0.05 mm apart — fifteen minutes, and the number is your machine's rather than someone else's.

08 / 9 sections

Six failures, and the order to try things

Nearly every failed print falls into one of these six, and within each one cause turns up far more often than the rest. Work down the last column in order, changing one thing at a time — otherwise you will not know which change fixed it.

Six common FDM failure modes
SymptomMost common causeTry in this order
Will not stick, corners curl (warping)Finger grease on the plate.Wash the plate with dish soap, then wipe with IPA → drop Z-offset 0.05 mm → raise bed temperature 5 °C → block draughts, close the enclosure → add a brim.
Stringing and webbingWet filament.Dry the spool to the material table → drop nozzle temperature 5 – 10 °C → increase retraction distance → raise travel speed → enable avoid crossing walls.
Layer shiftingA slack belt or a loose pulley grub screw.Check and tension the X/Y belts → tighten the pulley grub screws → look for something fouling the travel → reduce acceleration and travel speed.
Delamination, brittle parts that snapNozzle temperature too low for the material, or too much part cooling.Raise nozzle temperature 5 °C at a time → reduce fan speed (ABS, ASA and PA need almost none) → add wall loops → block draughts → check the filament is dry.
Under-extrusion, gappy walls, missing linesA partially blocked nozzle.Cold-pull or change the nozzle → check the extruder gear for wear and packed dust → raise temperature 5 °C → calibrate flow and E-steps → slow the print down.
Blobs at the seam, speckled surfaceThe seam is in the wrong place with no scarf.Switch the seam to Aligned and turn it to the back → enable smart scarf seam → tune retraction → bring flow back to 95 – 100 % → dry the filament.

Two things come before this whole table: dry the filament, and clean the plate. Neither is interesting, and between them they fix more failed prints than every setting combined — at no cost.

Read further:How to dry filament properly (and know when it's wet)

09 / 9 sections

Seven things before you press print

A twelve-hour print that fails in the eleventh hour almost always fails on one of these, skipped in the first minute. The list takes two minutes to run.

  1. 01Wipe the plate with IPA. If it has had a lot of use, wash it with dish soap first — alcohol does not lift all the oil.
  2. 02Look at the nozzle: no burnt plastic on the outside, no blob hanging off the tip.
  3. 03Check the filament: dried, not brittle, and no crossed wrap trapping a turn under another.
  4. 04The right material profile — nozzle and bed temperature matching what is actually loaded, not what ran last time.
  5. 05Z-offset set. Watch the first layer finish before you walk away.
  6. 06Step through the layer preview: support where it is needed, nothing floating, no unexpectedly empty layer.
  7. 07Ventilation on for ABS, ASA or resin. Enclosure closed for ABS, ASA or nylon.

Frequently asked

Frequently asked

For a stronger part, more infill or more wall loops?

More wall loops, in almost every case. The walls carry the bending moment when a part is loaded; the infill mostly stops the two shells collapsing together. Going from two to four wall loops usually buys more strength than going from 20 % to 50 % infill, for less material and less time.

How much clearance do two printed parts need to fit together?

Start at 0.05 – 0.15 mm for a press fit, 0.15 – 0.30 mm for a sliding fit, 0.20 – 0.40 mm for a snap fit, and add 0.10 – 0.30 mm to the diameter of any hole, because FDM prints holes undersized. These are trade convention rather than measured values: print a test bar with five holes 0.05 mm apart to find your own machine's number.

Why is my print still stringing after I tuned retraction?

Because the cause is usually not retraction but wet filament. Absorbed water boils at the nozzle and pushes plastic out even while the head is travelling. Dry the spool to its own temperature and time first, then retune retraction — otherwise you are tuning a setting that is not causing the problem.

What is the smallest layer height worth using?

Not below about 25 % of nozzle diameter and not above 75 %. On a 0.4 mm nozzle that is a usable range of 0.08 – 0.30 mm. For curved surfaces, adaptive layer height beats dropping the layer height of the whole model, because it prints thin layers only where they change anything.