Upgrades
Print quality triage
Start here when something is wrong and you do not know what. This page sorts symptoms into causes and sends you to the right fix.
By Michael W. · Published October 5, 2026
Two free checks first
Before changing a setting or buying a part, do these. Between them they resolve a large share of print quality problems:
- Wash the build plate with dish soap and hot water. Not alcohol, which redistributes skin oils rather than removing them.
- Dry the filament — in a dryer, a dehydrator, or carefully in an oven. Moisture imitates half the faults on this page.
Then print the same part again, with nothing else changed. If it improves, you have your cause.
The triage table
| Symptom | Most likely cause | Go to |
|---|---|---|
| First layer will not stick | Skin oils on the plate; Z offset too high | Print not sticking |
| Corners lifting off the plate | Adhesion: contamination, small footprint, cool bed | Why prints warp |
| Part cracks horizontally partway up | Layer splitting: too much part cooling, cold chamber | Why prints warp |
| Stringing between features | Wet filament first, then retraction settings | Wet filament symptoms |
| Popping or hissing from the nozzle | Moisture — this one is close to conclusive | How to dry filament |
| Filament snaps when bent | Wet, or over-dried | Wet filament symptoms |
| Nothing extrudes | Full clog, or a feed failure | Clogged nozzle |
| Extrusion thins through a print | Partial clog, heat creep, or worn extruder gears | Clogged nozzle, then AMS feeding |
| Over-wide lines, soft detail on everything | Worn nozzle — uniform and gradual | Nozzle lifespan |
| Ringing or ghosting on vertical faces | Belt tension; dry rails; high acceleration | Maintenance that matters |
| Overhangs curling or drooping | Insufficient or badly directed cooling | Best upgrades (cooling duct) |
| ABS or ASA warping and splitting | Chamber not pre-heated; too much cooling | How to print ABS |
| AMS fails to load filament | Snapped end, loose PTFE, binding spool, worn gears | AMS not loading filament |
| TPU buckles instead of feeding | Path geometry — feed direct instead | TPU in an AMS |
| Rough or furry surfaces | Moisture, over-extrusion, or a worn nozzle | Wet filament symptoms |
| Weak parts that snap easily | Moisture, over-cooling, or low temperature | Wet filament symptoms |
| Textured plate marks on a display face | Wrong plate surface for the print | Textured vs smooth |
| Machine has got louder | Dry rails, failing fan bearing, loose panel | Noise reduction |
The distinctions that save the most time
Gradual and uniform versus sudden and intermittent
A gradual, uniform decline across every print points at wear — a worn nozzle, worn gears, a tired plate. Sudden or intermittent faults point at a blockage or a feed problem. Replacing a part to fix an intermittent fault gets you the same fault with a new part.
Corner lift versus layer splitting
Both look like "warping" in a photograph and they need nearly opposite responses. Lift wants better grip and a hotter bed. Splitting wants warmer air and less cooling. Changing both at once is how a weekend disappears. Telling them apart.
Constant versus worsening through a print
A fault that is identical from the first layer to the last is usually a setting. A fault that gets worse as the print progresses points at something changing — a spool warming and releasing moisture, heat creep building, a chamber heating up.
The causes people reach for last and should reach for first
Moisture. Involved in more faults than any single mechanical cause, and checked last because it is invisible.
Plate contamination. Behind most first-layer failures, fixed with soap.
Maintenance. Dry rails and packed extruder gears produce symptoms that get blamed on parts you could buy. Maintenance that matters.
The cause people reach for first and should reach for last
Nozzle temperature. It is the easiest setting to change and it is rarely the problem. Before touching it, rule out moisture, the plate, cooling and maintenance — which is the entire argument of this page.
Where the fixes live
First layers. Moisture. Clogs. Feeding. Warping and splitting. Maintenance. Nozzle wear.
What to buy
Stock photograph of this product class, not of this specific unit.
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1. The one purchase that eliminates the most causes
SUNLU FilaDryer S2
A cited 35-70 C range, because moisture convincingly imitates half the faults on this page.
Moisture is the single most misdiagnosed cause in 3D printing, because its symptoms belong to other things — stringing, rough surfaces, weak parts, inconsistent extrusion, voids.
A dryer turns it from a suspicion into a tested variable: dry the spool, print the part again, and you know. A cited 35-70 C range covers PLA, PETG and TPU.
What it gets right
- 35-70 C covers PLA, PETG and TPU, which is most of what actually goes wet in a hobby workshop
- Quiet enough to run overnight in a room you sleep in
- The cheapest entry point that is still a real dryer rather than a warm box
What it does not
- 70 C ceiling means nylon, PC and PA-CF are out of range
- One spool at a time, which does not fit a four-color job
- No printing from the unit, so a dried spool starts re-absorbing the moment it comes out
| Temperature range (cited) | 35-70 C |
|---|---|
| Capacity | One spool |
| Diameters | Supports all common filament diameters |
| Noted | Quiet enough for overnight drying |
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2. The one that fixes first-layer problems
Bambu Lab Textured PEI Plate
Forgiving textured PEI on a 0.5 mm steel base, once a wash has not restored the old plate.
First-layer failures are the most common failure class, and contamination is the most common cause within it. The wash is free; the replacement is for when the wash does not work.
Powder-coated textured PEI, forgiving about Z offset, cited as resisting warping on large models in ABS, PC and nylon.
What it gets right
- Powder-coated texture grips hard without glue stick and releases when cool, which is the whole job
- The 0.5 mm steel base is stiff enough that it does not lift at the corners under a hot bed
- Hides first-layer imperfections, so a slightly off Z offset is forgiving rather than a failure
What it does not
- The texture transfers to your first layer — wrong plate for anything whose bottom face is a show surface
- PEI surfaces are consumable; skin oils and over-aggressive scraping both shorten their life
- TPU can grip hard enough on textured PEI to tear the surface on removal
| Surface | Powder-coated textured PEI |
|---|---|
| Base | 0.5 mm stainless steel with enhanced magnetic adhesion |
| Stated strength | Resists warping on large models in ABS, PC and nylon |
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3. The one that fixes a worn nozzle
Bambu Lab Hotend with Hardened Steel Nozzle, 0.4 mm
If filled filament wore the last nozzle out, hardened steel is the answer rather than another stainless one.
Wear is uniform and gradual — over-wide lines and soft detail on everything. Intermittent faults are clogs or feed problems and need diagnosing, not replacing.
Complete hotend assembly, HRA 74 hardened steel, 0.4 mm, for the P1P and P1S. A-series machines take their own part.
What it gets right
- Abrasive filament rounds a stainless nozzle fast — with the worst materials, a single print can do it
- Comes as a complete assembly, so the swap is a module change rather than a nozzle extraction
- 0.4 mm keeps your existing print profiles valid
What it does not
- Hardened steel conducts heat slightly worse than stainless, so very high-flow PLA needs a small temperature bump
- Pointless if you only ever print plain PLA and PETG — stainless lasts for years on those
- P1P and P1S only; the A-series and H-series need their own part
| Nozzle | Hardened steel, 0.4 mm |
|---|---|
| Fits | P1P and P1S (model FAH001-N-1) |
| Hardness reference | Hardened steel is cited at HRA 74 |
| Supplied as | Complete hotend assembly |
Questions people actually ask
How do I troubleshoot Bambu Lab print quality problems?
Do two free things first: wash the build plate with dish soap and hot water, and dry the filament. Then print the same part again with nothing else changed. Between them those two eliminate the most common causes, and they cost nothing. After that, work from your specific symptom rather than changing settings at random.
Why are my prints suddenly worse?
A sudden change points at something that changed - a new spool, a plate that has been handled, a clog forming, or a loose PTFE connector. A gradual decline across every print points instead at wear: a worn nozzle, worn extruder gears or a tired plate. The distinction decides what to check.
What setting should I change first?
None of them. Nozzle temperature is the easiest setting to change and it is rarely the cause, which is why people spend weeks on it. Rule out moisture, plate contamination, cooling and basic maintenance before touching a setting.
Is it my printer or my filament?
Dry the filament and print the same part again. If it improves, it was the filament. If nothing changes, it was not, and you can move on to the printer with one major variable eliminated. Moisture is involved in more faults than any single mechanical cause and is checked last because it is invisible.
Why does my print get worse as it goes?
Something is changing during the print. Common causes: the spool warming and releasing moisture, heat creep building up in the hotend, or the chamber getting hotter and softening layers. A fault that is identical from first layer to last is usually a setting instead.
Sources
- BIQU Panda range - plates, hotends, fans, extruder parts, storage - with fitment and materials - OpenELAB upgrade guide
- Textured and dual-texture PEI plate construction - PB Tech product listings
- Filament dryer specifications and positioning - SelfCAD dryer roundup
- Bambu Lab model descriptions and AMS capabilities - Wikipedia
Read this next
- When prints will not stick to the plateAdhesion failures in diagnostic order, starting with the free fix that resolves most of them, and the material-specific exceptions.
- How to tell if your filament is wetThe three near-conclusive signs of wet filament, the ambiguous ones, and the free test that settles it in one print.
- Clearing a clogged nozzleThe procedure for clearing a clog, plus the four causes behind it - because clearing without diagnosing gets you a repeat.
- Why your prints keep warpingHow to distinguish corner lift from layer splitting, and the four causes behind warping with the cheapest fixes first.
- AMS not loading filamentThe four real causes of an AMS feed failure in diagnostic order, three of which cost nothing and take minutes.
- Maintenance that actually mattersThe five maintenance jobs that change print quality, in priority order, plus the consumables worth stocking before you need them.