5. Introduction
5
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Traditionally, there are two ways of hobbyists making custom PCBs:
o Using toner transfer and chemical etchant -- can be tricky to get the right
materials, and the chemicals are nasty and messy.
o Paying a service like BatchPCB or OshPark – expensive and usually have to
wait a long time, like two or three weeks.
o There is a risk of injuries due to the chemicals involved.
o There is the problem of waste disposal. Toxic chemicals require a proper
disposal service.
6. Introduction
6
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Milling the PCBs on a CNC is a quick way:
o Quick turnaround - don't have to wait days or weeks for it to ship.
o The mill does the drilling.
o No messy acid to deal with.
o Once you have good settings, the process is easily repeatable.
o Two sided boards are possibly slightly easier than with etched boards.
o Inexpensive - you're just paying for blank circuit boards.
7. Objectives
o Specialized machines designed for prototyping printed circuit boards can
drastically speeds up the whole process making.
o The milling machine is capable of milling PCBs with extremely high
precision with basic tools. Easily achieve milled 0.1mm wide insulation
paths and drill 0.2mm holes.
o We also provide an extra feature of milling several objects on small scale
for Engineering students and hobbyists.
o Our aim is to provide cheap PCBs.
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8. Literature Review
Type of Etchant Corrosive? Problems with
Neutralizing or
Disposal?
Level of
Toxicity
1- Low
5 - High
Operational and
Disposal Cost
1 – Low
5 - High
Ferric Chloride
FeCl3
Yes. High. Moderate
problems with
both
1 3
Ammoniacal
Etchant
Yes. High in
ammonia.
Moderate
problems with
both
3 5
Cupric Chloride
CuCl2
Yes. High in
hydrochloric acid
Few problems
with both
3 1
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In early ages the method to prepare PCBs is using chemical etching. Now a
days the convention changes to milling of PCBs on CNC.
9. Literature Review
9
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Making PCBs using a CNC involves a small cutter that removes the excess
copper from the PCB substrate. The size of traces and features you can make
depends on several factors, including:
o Cutter width
o Machine accuracy
o Copper thickness
o While features as small as 0.1mm are possible, the average CNC user can
expect a trace width of 0.3mm
11. Proposed Methodology
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11
Electrical components required:
o Arduino UNO
o Stepper motor (1.8 degree step angle)
o Stepper motor driver (DRV8825)
o SMPS - 12v, 10A
o CNC shield V3
Software Required:
o Univarsal G-Code Sender
o FlatCAM,CopperCAM
o PCB Design Software(EAGLE CAD or EasyEDA)
16. Mapping to SDGs
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16
Goal
No.
Statement Description Justification
8
Decent Work and
Economic Growth
Promote inclusive and sustainable economic
growth, employment and decent work for all
Encourage the formalization and expansion of
micro, small, and medium-sized firms,
especially via financial inclusion, by promoting
advancement policies that help productive
activities, decent creation of jobs,
entrepreneurship, creativity, and innovation.
9
Industry, Innovation
and Infrastructure
Build resilient infrastructure, promote
sustainable
industrialization and foster innovation
To support economic growth and social well-
being, construct excellent, dependable,
sustainable, and high degree of flexibility,
including regional and trans border facilities,
with an emphasis on reasonable and equitable
use for everyone
There are 17 sustainable development goals given by United Nations Development
Programme (UNDP). Include the relevant SDGs from table given below.
17. Mapping to SDGs
-
17
Goal
No.
Statement Description Justification
11
Sustainable Cities and
Communities
Make cities inclusive, safe, resilient and
sustainable
Electronics are the vital part of
our life. All devices contains pcb
boards that make the devices
safe and secure
12
Responsible Consumption
and Production
Ensure sustainable consumption and production
patterns
Production of pcb using cnc is
more beneficial than vero
boards, chemically etched
boards etc
There are 17 sustainable development goals given by United Nations Development
Programme (UNDP). Include the relevant SDGs from table given below.
19. Project Timeline
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19
Dec-Jan
Electrical
Work
Stepper Motor and
CNC shield making
-
Arduino coding
3-axis making
-
Assembling
Oct-Nov
Mechanical
Work
Feb-Mar
PCB designing
-
G-code Formation
Software
Work
Apr-May
Finalization
Finalization of
physical appearance
-
Final testing
20. References
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o Overview to CNC etching of PCBs https://www.youtube.com/watch?v=tI6vF1ByR5s
o Online Price of all required parts
https://www.aliexpress.com/i/1005001314210565.html
o A complete procedure to make CNC including Mechanical, Electrical and Software
work https://www.instructables.com/Mini-CNC-complete-plans-and-instructions/
o Document contains process of making 3 axis with different style
https://www.instructables.com/How-to-Make-Mini-CNC-Machine/
o Alternate method for the mechanical work for the diy of CNC
https://all3dp.com/1/best-diy-cnc-router/
o CNC price online https://www.amazon.com/Desktop-Engraver-Control-
plasticEngraving/dp/B07FSYN62M
