Under-extrusion and over-extrusion in 3D Printing - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is under-extrusion in 3D printing?

Under-extrusion happens when the 3D printer does not push out enough plastic filament. This causes gaps, weak layers, or missing parts in the printed object.

beginner

What causes over-extrusion in 3D printing?

Over-extrusion occurs when the printer pushes out too much filament. This can make the print look messy with blobs, stringing, or thick layers.

beginner

Name two common signs of under-extrusion.

Common signs include thin or missing layers and gaps between lines of filament.

intermediate

How can you fix over-extrusion?

You can fix over-extrusion by lowering the extrusion multiplier or flow rate in the printer settings, or by checking if the filament diameter is set correctly.

beginner

Why is correct extrusion important in 3D printing?

Correct extrusion ensures the printed object is strong, smooth, and accurate. Too little or too much filament causes weak or ugly prints.

What happens when a 3D printer under-extrudes?

A The print has gaps and weak layers

B The print has blobs and thick layers

C The printer stops working

D The filament melts too fast

Under-extrusion means not enough filament is pushed out, causing gaps and weak layers.

Which setting can help fix over-extrusion?

A Increase print speed

B Use thicker filament

C Lower extrusion multiplier

D Raise bed temperature

Lowering the extrusion multiplier reduces the amount of filament pushed out, fixing over-extrusion.

What is a sign of over-extrusion?

A Gaps in the print

B Blobs and stringing

C Thin layers

D Missing parts

Blobs and stringing happen when too much filament is extruded.

Under-extrusion can be caused by:

A Clogged nozzle

B Too much filament

C High extrusion multiplier

D Low bed temperature

A clogged nozzle blocks filament flow, causing under-extrusion.

Why should filament diameter be set correctly?

A To control print speed

B To adjust bed temperature

C To change layer height

D To ensure correct extrusion amount

Correct filament diameter helps the printer push the right amount of filament.

Explain what under-extrusion and over-extrusion are in 3D printing and how they affect print quality.

Think about how too little or too much filament changes the printed object.

Describe two ways to troubleshoot and fix extrusion problems in 3D printing.

Focus on printer settings and physical checks.