Under-extrusion and over-extrusion in 3D Printing - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the sentence to describe under-extrusion in 3D printing.

3D Printing

Under-extrusion occurs when the printer [1] less filament than needed.

Drag options to blanks, or click blank then click option'

Afeeds too little

Bfeeds too much

Cfeeds

Dstops

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing under-extrusion with over-extrusion.

Choosing 'feeds too much' instead of 'feeds too little'.

Under-extrusion means the printer feeds too little filament, causing gaps or weak prints.

2fill in blank

medium

Complete the sentence to describe over-extrusion in 3D printing.

3D Printing

Over-extrusion happens when the printer [1] more filament than required.

Drag options to blanks, or click blank then click option'

Afeeds

Bfeeds too little

Cfeeds too much

Dstops

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing over-extrusion with under-extrusion.

Choosing 'feeds too little' instead of 'feeds too much'.

Over-extrusion means the printer feeds too much filament, causing blobs or rough surfaces.

3fill in blank

hard

Fix the error in the sentence describing a cause of under-extrusion.

3D Printing

A common cause of under-extrusion is a [1] nozzle that blocks filament flow.

Drag options to blanks, or click blank then click option'

Awide

Bclogged

Cclean

Dheated

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing 'clean' which would not block filament.

Confusing 'wide' with blockage.

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

4fill in blank

hard

Fill both blanks to complete the sentence about fixing extrusion issues.

3D Printing

To fix under-extrusion, check the [1] and adjust the [2] settings.

Drag options to blanks, or click blank then click option'

Anozzle

Btemperature

Cbed

Dspeed

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing 'bed' which relates to print surface, not extrusion.

Confusing speed with temperature settings.

Checking the nozzle for clogs and adjusting temperature can help fix under-extrusion.

5fill in blank

hard

Fill all three blanks to complete the dictionary comprehension about extrusion checks.

3D Printing

checks = { [1]: [2] for [3] in ['nozzle', 'temperature', 'speed'] if [2] != 'optimal' }

Drag options to blanks, or click blank then click option'

A'component'

B'status'

Ccomponent

D'optimal'

Attempts:

3 left

💡 Hint

Common Mistakes

Using string literals instead of variable names for loop variable.

Mixing up keys and values in the comprehension.

This comprehension creates a dictionary of components and their status if the status is not 'optimal'.

Practice

1. What does under-extrusion in 3D printing cause?

easy

A. Gaps or holes in the printed object

B. Blobs or excess plastic on the print

C. The print bed not heating properly

D. The nozzle clogging completely

Solution

1. Step 1: Understand extrusion basics

   Extrusion controls how much plastic the printer pushes out through the nozzle.

2. Step 2: Identify under-extrusion effects

   Under-extrusion means too little plastic is pushed out, causing gaps or holes in the print.

3. Final Answer:

   Gaps or holes in the printed object -> Option A

4. Quick Check:

   Under-extrusion = gaps [OK]

Hint: Under-extrusion = too little plastic = gaps [OK]

Common Mistakes:

• Confusing under-extrusion with over-extrusion
• Thinking under-extrusion causes blobs
• Mixing extrusion issues with bed heating problems

2. Which adjustment is commonly used to fix over-extrusion in 3D printing?

easy

A. Decrease the flow rate

B. Increase the print speed

C. Lower the nozzle temperature

D. Increase the bed temperature

Solution

1. Step 1: Understand over-extrusion causes

   Over-extrusion happens when too much plastic is pushed out, causing blobs or excess material.

2. Step 2: Identify correct adjustment

   Decreasing the flow rate reduces the amount of plastic extruded, fixing over-extrusion.

3. Final Answer:

   Decrease the flow rate -> Option A

4. Quick Check:

   Over-extrusion fix = lower flow rate [OK]

Hint: Lower flow rate to fix over-extrusion blobs [OK]

Common Mistakes:

• Increasing flow rate instead of decreasing
• Changing bed temperature which doesn't affect extrusion
• Confusing print speed with flow rate

3. A 3D print shows gaps between layers and weak bonding. Which code adjustment would most likely fix this?

flow_rate = 0.8  # current flow rate
print_speed = 60  # mm/s
# What should be changed?

medium

A. Increase print_speed to 90

B. Decrease print_speed to 30

C. Decrease flow_rate to 0.5

D. Increase flow_rate to 1.0

Solution

1. Step 1: Analyze print problem

   Gaps and weak bonding indicate under-extrusion, meaning not enough plastic is extruded.

2. Step 2: Choose correct parameter change

   Increasing flow_rate from 0.8 to 1.0 increases plastic output, fixing under-extrusion.

3. Final Answer:

   Increase flow_rate to 1.0 -> Option D

4. Quick Check:

   Under-extrusion fix = increase flow rate [OK]

Hint: Fix gaps by increasing flow rate, not speed [OK]

Common Mistakes:

• Decreasing flow rate worsens under-extrusion
• Changing print speed alone doesn't fix extrusion amount
• Increasing print speed can worsen gaps

4. A 3D print has blobs and stringing. The flow rate is set to 1.2 and print speed is 40 mm/s. What is the most likely error?

medium

A. Nozzle temperature is too low causing clogging

B. Print speed is too high causing under-extrusion

C. Flow rate is too high causing over-extrusion

D. Bed temperature is too high causing warping

Solution

1. Step 1: Identify symptoms

   Blobs and stringing usually mean too much plastic is extruded, called over-extrusion.

2. Step 2: Match symptoms to settings

   Flow rate of 1.2 is high, likely causing excess plastic output and blobs.

3. Final Answer:

   Flow rate is too high causing over-extrusion -> Option C

4. Quick Check:

   Blobs = over-extrusion = high flow rate [OK]

Hint: Blobs? Check if flow rate is too high [OK]

Common Mistakes:

• Blaming print speed instead of flow rate
• Confusing under-extrusion symptoms with over-extrusion
• Assuming temperature issues without evidence

5. You notice your 3D print has thin layers with gaps but increasing flow rate causes blobs. What combined adjustment can fix this?

hard

A. Decrease flow rate and increase nozzle temperature

B. Increase flow rate slightly and reduce print speed

C. Increase print speed and decrease bed temperature

D. Keep flow rate same and increase print speed

Solution

1. Step 1: Analyze problem symptoms

   Thin layers with gaps indicate under-extrusion, but increasing flow rate alone causes blobs (over-extrusion).

2. Step 2: Find balanced solution

   Increasing flow rate slightly adds needed plastic, while reducing print speed allows better layer bonding without blobs.

3. Final Answer:

   Increase flow rate slightly and reduce print speed -> Option B

4. Quick Check:

   Balance flow and speed to fix extrusion issues [OK]

Hint: Balance flow rate and speed to fix gaps and blobs [OK]

Common Mistakes:

• Changing only flow rate causing new problems
• Ignoring print speed effects on extrusion quality
• Assuming temperature fixes extrusion amount