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1. 1/22
Introduction to
DIY CO2 Laser
BY KIWI

2. Personal Introduction
● Kee Wee Teng, Aka “KIWI”
● Full-time
– Ministry of Defence
● Personal-time
– FOSSASIA Organiser Singapore
– Educator
– Inventor
● Area of Interests
– Digital Fabrication Machines
– Training and Education
–

3. 3/22
Sessions Run Through
● Introduction to DIY CO2 Laser (90mins)
– Basic understanding of what is needed to embark on the
DIY CO2 laser project
● DIY Laser Design and Considerations (90mins)
– To know the design options of the respective laser cutter
modules and to understand the considerations behind it
● DIY Laser Construction and Considerations (90mins)
– Techniques and method of constructions, testing and
troubleshooting
● Laser Cutting (90mins)
– Material, cutting techniques and projects

4. 4/22
Scope
● What CO2 laser cutter can do (5mins)
● Laser Theory Quicky (5mins)
● Basic Laser Cutter Components (15mins)
● Basic Design Concepts (15mins)
● Safety Quicky (10mins)
● Regulations (5mins)
● Practical Demo and Constructions Run through
(20mins)
● Q&A

5. 5/22
What CO2 Laser Cutter Can Do?
● 2D cutting/engraving on organic material
– Wood, leather, Plastic, Fabric, Paper....
● Structural Fabrication
– Artwork
– Market ready fabrication

6. 6/22
Laser Theory Quicky
● Medium
– Gaseous or solid (e.g. CO2 Laser cutter, and
Nd:YAG)
● Wavelength (Common used laser)
– CO2 is 10.6micron (IR) – invisible, mostly absorb by
organic material. Metal cutting requires > 160W with
oxygen assist.
– Nd:YAG is 1.06micron(IR)– invisible, absorb by
metal but not most organic material.
– Diode laser e.g. UV 443/5nm – visible light, for
engraving and cutting of non-reflective thin material
(Paper, fabric, foam...).

7. 7/22
Laser Theory Quicky
● Comparison
– CO2 laser is more widely used in both industrial and DIY
communities due to its versatility and low cost.
– Nd:YAG is used mainly in industry dealing with metal
engraving or cutting only.
– Diode Laser is simple and can be easily integrated into
3D printer. But the capability is limited. Vis-a-vis it is
more expensive than CO2 laser. (Cost-to-power ratio)
● CO2 Laser Power Ranges
– 40W is minimum for useful cutting (<40W is engraving
only, or cutting very thin material (<1mm))

8. 8/22
Laser Theory Quicky

9. 9/22
Basic CO2 Laser Cutter
Components
● Hardware : 4 main modules
– CO2 Laser Module:
● Laser pump and cutting optics & mount, cutting bed
– Router Module:
● XYZ Axis movement
– Control Module:
● Controller, Motor Driver, Laser driver
– Support Module:
● Air, Water, Exhaust
● Software/Firmware : Inkscape, Repetier, Ponterface

10. 10/22
CO2 Laser Module

11. 11/22
CO2 Laser Module
● Components
– Consumables
● CO2 Laser Tube – IR Laser source
● 1st Mirror, 2nd Mirror, Cutter Mirror – Design dependant
● Cutting Lens – Various Focal Length based on cutting
needs
– Non-Consumables
● Power supply unit – 220v Single Phase input, 20kv-40kv
output, laser control interfaces
● 1st Mirror, 2nd Mirror mounts – 20mm/25mm option
● Cutting head

12. 12/22

13. 13/22
Router Module
● To Mechanically guide the cutter head in X/Y
axis, or Cutting bed in Z axis
● Components
– Typical 3D printer setup
● Stepper motors: Nema 17
● Limit switches
● GT2 Belt Drive
● Linear rails – your choice
– Typical Setup
● Parallel Y axis

14. 14/22
Control Module
● KISS principle
– RAMPs 1.4/MEGA 2560
– Stepper drivers as required
– D5 pin/Fan out/Extruder for laser on/off signal
output
– 12V PSU – recommend >8A to provide sufficient
power to Exhaust and water pump

15. 15/22
Support Module
● Air pump – 50-100PSI is good enough, continuous
operation type(not your car/bike air pump!)
– To assist the laser cutting process
– To protect the lens
● Water cooling system (Critical to the survivability of
the laser tube!)
– 12V water pump and at least 1000ml of water tank for
useful cutting duration. Or with radiator.
– Tap water is good enough, but need to change every
2 weeks (Algae)

16. 16/22
Support Module
● Exhaust system (A must for your health sake!)
– At least 3A 12V fan to effectively draw the exhaust
away
– Duct it out of the window if you dun care about your
neighbour, else filter it
– Exhaust Filter – Activated Carbon + HEPA13 filter

17. 17/22
Basic Design Flow
● Principal Consideration
– Desired cutting area
● Unrealistic to have too big cutting area with a
stationary laser source.
– CO2 laser power attenuate with distance, especially so
in “smoky” environment
– Either have a Higher power laser (80W) and except low
efficiency or make the laser tube move with the cutter
● For DIY: limit your cutting area to 420mm x 300mm
(A3 size) with 40W CO2 laser system. (else suffer
inconsistent cutting power across the work area)

18. 18/22
Basic Design Concepts
● Design Options
– 3 Mirrors (including cutting head mirror)
● Most common design layout
– 2 Mirrors (including cutting head mirror)
● Not space efficient, but easier in alignment
– 1 mirror
● Tube will move with Cutter (i.e Higher power motor
required), not space efficient, much easier in alignment
● Moving cutting table (for very small work area)
– 0 mirror??

19. 19/22
Safety Quicky
● 3 things that will kill you in DIY CO2 Laser!
– The high voltage
– The laser
– The exhaust!!
● The High Voltage
– The Laser PSU output is 20KV-40KV and if the
wiring is not done properly, SPARKS WILL FLY!
● No alligator clip!
– Either you get a nasty shock or/and your controllers
will be fried
● Fire Hazards from accumulated debris, so clean
them routinely!

20. 20/22
Safety Quicky
● The Laser (Class 4)
– CO2 laser will burn flesh, either directly or from
reflected source
● So make sure the laser cutter is fully encased with child-safe
lock
– UV intensity at the focal point is that of the sun x
>100times! So wear eye protection with correct OD
ratings. (Please dun stare at it, I know it is tempting....)
● The Exhaust
– For Wood cutting - No difference from the health impact
of HAZE at PSI 400
– For Plastic cutting – Fumes are cancerous! PVC gives
off toxic fumes that destroy the machine too!

21. 21/22
Regulations
● Still in the grey area for DIY
● SG NEA regulation applies to
company/organisation for dealing with or
owning Class 4 laser, and workers operating
them
● 3 Licenses
– N1 for Company manufacturing and/or dealing with
laser apparatus
– N2 for Company ownership
– N3 for workers operating them
– (SGD$38 per 3 months for each license)

22. 22/22
Practical DemoTime!

23. 23/22
Myth Busting
● 3D laser cutting
– Cutting is a 2D business
– Z axis movement is to maintain consistent engraving
power across uneven surfaces
– Depth of cut is not controllable as you can't monitor it
● CO2 laser system without exhaust ducting, placed
in the middle of the kitchen or living room
– Where will the exhaust go? Safety?
● Mounting Laser module (Diode laser) directly on
3D printer. Sure...provided you have eye
protection for everyone

24. 24/22
“With Great Power, Comes Great
Responsibilities”
Be Safe to Yourself and Others!!

25. 25/22
Q&A
Email:
Avalonworkz@gmail.com