3D printing support

3D printing problems solved step by step.

An open support centre for anyone: printing problems solved step by step, profiles of the most common printer brands and links to the official guides we actually use in the workshop.

Solved problems

24 typical failures, with causes and concrete values.

Printer brands

10 profiles with quirks, tips, a PDF guide and official support.

Printer models

12 model pages: A1, P1S, MK4S, Ender 3, Kobra 3...

Guides and tools

Slicers, calibration, models, CAD and materials.

Solved problems

The failures every printer owner runs into, explained the way we'd explain them to a workshop mate: most likely cause first, then a step-by-step fix.

Adhesion and warping

The corners of the part are lifting (warping)

The print starts well, but from 1-2 cm in height, the corners peel off the bed and the base curves upwards. On large, flat parts, it is almost always the first thing to fail.

6 minSee the fix

Adhesion and warping

The first layer isn't sticking to the bed

Filament extrudes, but sticks to the nozzle and drags, or forms loose threads that come unbonded on their own. Sometimes it starts well in one area and fails in another.

6 minSee the fix

Adhesion and warping

The base of the part is flared (elephant foot)

The first few layers stick out by a few tenths of a millimetre compared to the rest of the part, leaving a lip. The part does not sit flat and mating parts become impossible to fit.

4 minSee the fix

Adhesion and warping

How to calibrate the nozzle height (Z-offset)

Not a fault as such: it is the setting that determines bed adhesion, elephant's foot, bottom surface finish, and a good deal of your tolerances.

5 minSee the fix

Extrusion and nozzle

My nozzle is clogged

The extruder clicks or slips, very little or no material comes out, and the part becomes hollow above a certain height. In a partial clog, the flow drops but does not stop completely.

7 minSee the fix

Extrusion and nozzle

Less material comes out than expected (under-extrusion)

Lines do not touch each other, walls remain translucent and fragile, and the infill looks like a mesh full of holes. The part breaks by hand.

6 minSee the fix

Extrusion and nozzle

Too much material coming out (over-extrusion)

Surfaces with blobs and ridges, bulging corners, nozzle dragging over previous layers and the part measuring over size.

4 minSee the fix

Extrusion and nozzle

Strings and cobwebs appear between parts (stringing)

Fine strings appear between towers, holes or separate parts when removing the print. Almost always in PETG; in PLA only if something is wrong.

5 minSee the fix

Extrusion and nozzle

The extruder clicks and slips

A rhythmic clicking sound from the extruder, filament dust under the machine and a marked flat notch in the filament when you pull it out.

5 minSee the fix

Extrusion and nozzle

Filament snaps inside the tube on its own

When loading filament, it snaps with a sharp crack, or the print stops and you find a loose piece inside the tube.

4 minSee the fix

Layer quality

The print is shifted halfway up

Above a certain height, the whole part shifts a few millimetres in X or Y and continues printing from there. The result is a clean step.

5 minSee the fix

Layer quality

Waves or shadows appear on walls (ringing)

Smooth waves repeat and fade out after every corner or hole. Best seen under raking light.

5 minSee the fix

Layer quality

The part breaks between layers

The part separates cleanly along a horizontal line, as if it were glued sheets. It breaks with little force and always in the direction of the layers.

6 minSee the fix

Layer quality

Holes come out smaller than they should

You design a 5 mm hole for a 5 mm screw and the screw won't go in. An 8 mm shaft is loose or doesn't fit at all.

5 minSee the fix

Layer quality

Supports won't come off or they ruin the surface

Supports are fused to the part and have to be ripped off with pliers, leaving marks and craters on the surface.

5 minSee the fix

Layer quality

The top surface is rough or has small holes

The final layer looks like a mesh, with small holes or separated lines, instead of a smooth, uniform surface.

4 minSee the fix

Materials

PLA, PETG or ABS? Which one to use in each case

This isn't a failure: it's the single decision that determines whether the part will last. Choosing the wrong material leads to parts that warp in the sun or snap on first use.

5 minSee the fix

Materials

When should you dry filament and how do you do it?

Popping sounds and bubbles during extrusion, visible steam, rough surface finish, severe stringing, and parts that snap easily.

5 minSee the fix

Materials

Are 3D printer fumes or odours dangerous?

Sweetish odour (PLA), strong burnt plastic smell (ABS), headache after hours with the printer in a small room.

4 minSee the fix

Materials

Flexible TPU keeps getting jammed and prints poorly

The filament bends inside the extruder and slips out the sides, the part comes out stringy all over, or extrusion stops completely.

5 minSee the fix

Settings and slicing

How many perimeters and how much infill should I use?

This isn't a failure: it's the setting where most people waste time and material. Neither 100% infill is the answer, nor does 10% work for everything.

5 minSee the fix

Settings and slicing

How do I place the part on the bed?

The part snaps right where it shouldn't, supports are everywhere, or the visible surface looks untidy. It's almost always a matter of orientation.

5 minSee the fix

Maintenance

How to change the nozzle without damaging the hotend

Increasingly thin lines, unresolved under-extrusion, plastic leaking from the heatbreak, or simply wanting to print faster.

5 minSee the fix

Maintenance

What maintenance does a 3D printer need?

The printer no longer prints like it did on day one: more noise, more failures, less clean layers. Almost always it is a lack of maintenance, not a fault.

5 minSee the fix

Printer brands

Every machine has its quirks. Here's what's worth knowing about each brand, the tricks we use ourselves and a direct link to the official documentation.