Intro to Designing and Making Your Own PCB Boards

Glossary:

PCB = Printed Circuit Board
EDA = Electronic Design Automation software
hobbyist PCBs = single- or double-layer boards without high-frequency circuits

Designing and making PCB boards is one of the easiest, least expensive, least messy CAD/CAM hobbies. Most people use EDA software, which is specific to designing and making PCBs.

3D View of PCB created with EasyEDA Designer illustrating annotations, fiducials (pick and place registration dots), copper pour, plated grounding hole and mounting holes

In 2021, there’s 5 main options for hobbyists to learn and/or make PCB boards:

use PCB EDA software, simulate in SPICE, view in 3D, then stop there
use PCB EDA software and click a menu to send to an online PCB fab (turn-around time about 2 weeks)
use PCB EDA software and make your own PCB boards with a chemical process (better results than desktop CNC machines)
use PCB EDA software and make your own PCB boards with a general purpose CNC machine (results depend on skill)
use PCB EDA software and make your own PCB boards with a desktop PCB CNC machine (starts at $4,000, results are hit or miss)

Option 1 is good for hobbyists who want to learn how to use EDA software, with advanced features including vias/holes, SMT and annotations. This is a good route if you don’t really need to make a physical board today, but want to know the initial skills for future use.

Option 2 is good for people who want to use advanced design features (see #1), and actually need to fab the board professionally with those features. EasyEDA’s fab, JLCPCB, can also populate boards if you use their recommended parts and they’re in stock.

Option 3 is good for people who want to design basic boards and also physically make simple boards themselves. It’s unlikely the average hobbyist would be able to successfully make complex boards with annotations, which requires silk screening (unless traces are used for lettering), many vias or holes (unless copper PCB rivets are used), multi-layer or SMT (requires skilful hand soldering or wave soldering.)

To get a high-resolution image for chemical processing, export as SVG instead of Gerber, then scale and print using an SVG application like Inkscape (free.)

For Option 3, you do chemical processing, and for holes, operate a drill press. New, diamond-coated or carbide drill bits are recommended to avoid shredding PCBs. Chemical processing is the cheapest and highest-resolution method, and there’s simplified “no-heat” methods that use glossy-paper inkjet or laser printer transfers instead of UV light now.

For Option 4, you use a CNC machine and/or drill press. This is a possible option for people who already own a CNC machine. Use diamond-coated or carbide drill bits, do a height-map, cut at 0.1 mm depth, and do a test PCB to see what the resolution of your CNC machine is. Often good SMT traces are difficult with low-end CNC machines. Some people have had luck with careful use of a low-end 3018 machine. The disadvantages are messiness, lack of silk-screening annotations, and effort making vias.

For Option 5, follow the instructions with your desktop PCB CNC machine carefully. Some people have good luck with these machines, and some don’t, due to the limited torque of the built-in motors and lack of rigidity. Some professional engineers have reported good results, and benefit from same-day turnaround on their prototypes. Some users have said they need to watch the machine like a hawk to avoid mishaps, or avoid SMT designs. The disadvantages are lack of silk-screening annotations, and effort making vias.

It’s recommended to use a vacuum hose with CNC machines to keep the work area clean of chips, otherwise the occasional trace can be damaged and the drill bit can wear faster, causing shredding.

The materials and chemicals used in “no-heat” chemical processing are:

some type of PCB, depends on process or machine
baby oil for transferring your ink jet- or laser-printed circuit from glossy paper to the PCB
ferric chloride to etch the copper (or alternative)
nail polish or diluted acetone to remove ink from board
electrical lacquer for coating the final board
rubber gloves, mask and steel wool or scotchbrite (avoid using sandpaper on copper traces, but ok on PCB edges)
copper PCB rivets

Isopropol alcohol is commonly used to wipe boards after CNC milling.

If you drill holes, a drill press or drill stand ($50) is recommended to make the holes vertical, to avoid shredding the board, and to preserve the sharpness of the drill bits. Sizes 0.8 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, and 3.0 mm are commonly used. Plan to use bits that use the same size chuck to save effort and time. (The most commonly-used drill bit is 0.8 mm, but some people have to use 0.9 mm if leads don’t fit. This bit is also used to pre-drill larger holes.) If you’re trying to search for drill bits, try lapidary sources.

Note that final traces need to be tinned or coated (electrical lacquer) to reduce corrosion.

Also, chemical methods have high-enough resolution for SMT, while desktop PCB milling machines often don’t.

It’s important to realize the multiple functional properties of a PCB:

electrical (EMF/electron drift transmission through traces, wires and solder)
thermal (heat is dispersed along traces/pours, vias and air)
mechanical (strong component connections)
dimensional (rigidity in XYZ)
electromagnetic (high power, current and frequency applications create crosstalk via electromagnetic fields in air)

PCB Substrates: Knowing Your Dielectric Material’s Properties

Below are some recommended EDA software:

Free but Cloud:

– EasyEDA: My Review (Free)

Free and no-cloud:

– KiCad: Homepage, My KiCad Tips, KiCad Links (GPLv3, various Open Source licenses, funded by CERN)

Other EDA Programs:

– Diptrace (freeware limits pin count until paid upgrade)
– DesignSpark PCB (adware)
– Fritzing (GPLv3)
– AutoDesk 123d Circuits Tinkercad (Free)
– EveryCircuit ($15)
– gEDA (GPL)
– PCB (GPL)
– ExpressPCB (Nice FAQ on Placing Components) (Free)

Diptrace vs KiCad

Cut2d Pro: “Cut2D Pro gives you the power to produce complex 2D patterns with profile, pocket, drill and inlay toolpaths. With unlimited job and toolpath size, true shape nesting & job set-up sheets.

Cut2D Pro has easy to use vector drawing and editing tools with powerful 2D machining strategies for CNC routing, milling or engraving and provides a powerful but intuitive software solution for cutting parts on a CNC Router.”

Other CAD/CAM Software

– gerbv Viewer for Gerber (GPLv2)
– Flatcam Converts formats including Gerber to gcode (free)

DIY CAM PCB Mills

Wegstr: PCB making, PCB prototyping quickly and easy – STEP by STEP ($4,000+ plus consumables)
The Wegstr CNC prototyping mill
Double layer PCB prototyping 0.1 mm traces/spaces
CNC PCB – high quality with the budget 3018 CNC
FlatCam 2 sided PCB milling on a CNC
Bantam Tools CNC: Milling Double-Sided PCBs with the Desktop PCB Milling Machine
Creating a homemade PCB with the Voltera V-One PCB Printer ($4,100+)

DIY Chemical Process PCB Making

DIY PCB Toner Transfer (No Heat) & Etching – Easiest
DIY PCBs At Home (Single Sided Presensitized) – Nice UV Process
DIY PCB Fabrication (Dry Film Inkjet Method)
DIY PCB Shaker For Etching (Low Cost Rocker/ Agitator)
Exposing, Developing, Etching and Drilling PCBs – My (Current) Way (with drilling and isolation slots)
Making PCBs (with vias)

Misc Links

– GadgetReboot: Youtube, Github KiCad Projects

– eprpartner.com: Small but mighty: fiducial marks and their purpose
– ema-eda.com: Orcad Lite Limits

Amazon: “Lab Shaker”

Flake Multimeter Watch
Action Box DIY Pro Machines
altium.com: Are Fiducial Marker Placements on PCBs Still Necessary with Modern Manufacturing Capabilities?
Investigation on the efficiency of thermal relief shapes on different Printed Circuit Boards
Mounting hole on a PCB (Fiducials)
My Experience Using the Online PCB Software EasyEDA
EasyEDA API

PCB Electronics Theory