3D CAD/CAM, 3D printing, routing and PCB production

Lecture at Nordic VUSHF MeetingJune 15. 2019

LB8XTom Twisttom@twist.no

Agenda

● 3D modeling (CAD).● Getting 3D models from Internet.● Slicing for 3D printing, 3D printers, filament types.● CAM (Computer Aided Manufacturing), G-code.● PCB design.● PCB production.

3D modeling programs

● SketchUp (Trimble)● Tinkercad (Autodesk) Free, Web based● DesignSpark Mechanical (RS) Free● SolidWorks (Dassault Systèmes)● Inventor (Autodesk)● Fusion 360 (Autodesk) Free for Hobbyists, students and startup companies● Blender (Open source) Free form modeling● Meshmixer (Autodesk) Free● FreeCAD (Open source)● OpenSCAD (Open source) Script based “programming”

SketchUp

● Easy to get started● Limited free version, no extensions● Make and Pro available at cost● Windows and MacOS● No personal experience● https://www.sketchup.com

Tinkercad

● Web based● Free● Limited● No personal experience● https://www.tinkercad.com

Designspark Mechanical

● Free● Integrates with RS-online webshop● Based on SpaceClaim, from ANSYS● Limited: No export, no plugins● No threads, no 2D drawing creation, but available at high cost● IGES and STEP import/export at high cost● No personal experience● https://www.rs-online.com/designspark/mechanical-software

SolidWorks

● Industry standard● Many learning resources● Expensive, but free for students● Heavy on system resources (in my experience)

● Needs third party CAM plugin● Windows only● https://www.solidworks.com

Inventor

● Industry standard, #2 ?● Expensive● Windows only● No personal experience● https://www.autodesk.com/products/inventor

Fusion 360

● New kid on the block● Developed from scratch, based on experiences from Inventor and more● Many learning resources● Free for hobbyists, students and startup companies with revenues less than US$ 100 000● Innovative combination of modeling and assembly● Integration with Eagle PCB design. Sheet metal bending● Includes 5-axis CAM, simulation and animation● Windows and MacOS● Requires registration and login● https://www.autodesk.com/products/fusion-360

Meshmixer

● Free● "Swiss Army Knife" for 3D meshes● Windows and MacOS● No personal experience● http://www.meshmixer.com

Blender

● Free form design, sculpting● Open source = free● Multi platform● No personal experience● https://www.blender.org

FreeCAD

● 3d solid modeling● Open source = free● Multiple Workbenches for different tasks● Parts modeling, analysis, simulation● Active development team● Very active user forum● Multi platform● Limited personal experience● https://www.freecadweb.org

OpenSCAD

● Script-only based modeller● Supports parameters, modules and libraries● Good documentation● Can be used to make very complex designs, e.g. Mendel 90 3D printer● Easy to make quick models● Mostly popular with programmers● Exports STL files for 3D printing● Multi platform● https://www.openscad.org

Why Fusion 360

● Modern, cloud based, but works offline.● Full parametric 3d solid modeling● Moderate on system demands● Extensive, features being added all the time.● Nice conditions for hobbyists, students and startups● Steep learning curve at first, but few limitations.● Can exchange design data with many different systems● Can import STL files, convert them to solids, modify them and combine with 3D model● Scripting, in Python and C++● Can be used for most modeling and drawing tasks● Massive online support on YouTube and forums● Popular with makers, since many competitors have changed their conditions

Fusion 360 resources

● Lars Christensen, YouTube https://www.youtube.com/user/cadcamstuff/videos

● Fusion 360 Tutorial for Absolute Beginners— Part 1https://www.youtube.com/watch?v=A5bc9c3S12g

● Paul McWhorter, YouTube https://www.youtube.com/user/mcwhorpj/videos

● NYC CNC, YouTube (mechanical) Fusion 360 Friday https://www.youtube.com/playlist

Fusion 360 Demo

● Live demo

3D models on Internet

● Thingiverse https://www.thingiverse.com

Mostly STL files, but also for modeling● GrabCAD https://grabcad.com

Both 3D models and STLs● Google 3d models and STL files

Thingiverse example

● https://www.thingiverse.com/thing:2030237

Some 3D printer brands

● Creality● Flashforge (Clas Ohlson)● Prusa● Ultimaker● Wanhao

Creality Ender 3

● Good starter printer, but comes as a kit● About 1 hour assembly time● Affordable, current price in Norway: NOK 2595,-● Machine size 440 x 410 x 465 mm, ~ 7 kg ● Printing volume 220 x 220 x 250 mm● Nozzle diameter 0.4 mm● Max nozzle temp 255 °C, max hot bed temp 110 °C● Can print most filament types● USB or µSD card

Creality Ender 3

Filament types

● Diameter 1.75 mm (most common) and 2.85 mm

Normal materials:● PLA (PolyLactic Acid) Most common● ABS (Acrylonitrile butadiene styrene) Somewhat difficult to print● PETG (Polyethylene terephthalate glycol-modified) Upcoming,

easy to print● ASA (Acrylonitrile styrene acrylate) UV resistent, outdoor usage

moderately easy to print

Special filament types

● Flexible● Carbon fiber reinforced● Magnetic● Conductive● Fluorescent● Glow in the dark● Color changing● Metal particles● Wood fibers● Clay/ceramic● Wax (lost wax casting)

3D printer slicers

● Cura (Ultimaker) Freehttps://ultimaker.com/en/products/ultimaker-cura-software

● Slic3r (Open source) https://slic3r.org● Simplify3D (commercial) https://www.simplify3d.com● Prusa has it’s own version of Slic3r

https://www.prusa3d.com/prusaslicer/

Cura slicer

PCB Design software - EDA

● EDA = Electronic Design Automation● KiCad (Open source)● Eagle (Autodesk) Free + subscriptions● Fritzing (Open source)● Designspark PCB (RS) Free● EasyEDA Web based, Free + subscriptions

KiCad

● Schematic capture, PCB layout/routing, Gerber viewer● Open source = free● Multi platform● Design rules check, autorouter● Many libraries available● Can import libraries from Eagle and other EDAs● Python scripting● No personal experience● http://www.kicad-pcb.org

Eagle PCB design

● Schematic capture, PCB layout/routing and CAM generation● Free for hobbyist, limited to 80cm², 2 layers● Subscription: Standard 160cm², 4 layers, Premium unlimited area, 16 layers● Design rules and decent autorouter● Large libraries, also from 3rd parties● Integration with Fusion 360● Requires registration and login● https://www.autodesk.com/products/eagle

Fritzing

● Schematic capture, PCB layout and breadboard layout● Open source = free● Multi platform● Quite limited, awful to make components● Good to document breadboard constructions● http://fritzing.org/home/

Designspark PCB

● Schematic capture, PCB layout/routing and Gerber generation

● 1 m² area, 32 layers● Integrates with RS-online webshop● No personal experience● https://www.rs-online.com/designspark/pcb-software

EasyEDA

● Web based● Free + subscriptions● Local version available● No personal experience● https://easyeda.com

Why Eagle?

● I have used Eagle since before 2000, both professional and for hobby● Preferred tool among hobbyists/makers● Easy to use, once mastered● Good library support, easy to define new components● Good DRC (design rules check) and autorouting● Programmable/extensible with SCR and ULP● SCR = Script, ULP = User Language Program● Today I would probably choose KiCAD or Designspark PCB

Eagle demo

● Demo

Gerber code - Excellon

● Gerber code was control code for photo plotters● Now industry standard● Excellon is drilling code● Tool tables for drilling

PCB prototyping with CNC

● Isolation routing● Drilling● Slot milling● Contour milling

Isolation routing

Issues with PCB CNC routing

● Flatness of PCB● Must use auto leveling to achieve acceptable results● Auto probing the PCB, and applying the height map to

correct the G-code

PCB CAM programs

● FlatCAM (Open source) http://flatcam.org● Pcb-gcode (plug-in for Eagle) free● ChiliPeppr (Web based) free

Hobbyist PCB methods - etching

● Tape or marker pen method● UV transfer method from film● Laser printer transfer method (direct transfer)● Spray paint + laser exposure

Etching methods:● Ferric chloride (messy)● Sodium or ammonium persulphate● Hydrogen peroxide + Chloric acid (more dangerous)

PCB - Non etching methods

● Removal of copper with knife and solder iron● Dremel milling (by hand)● CNC milling and drilling● CNC + EDM (Electrical Discharge Machining)

https://hackaday.com/2019/05/13/prototyping-pcbs-with-electrical-discharge-machining/

● Direct laser cutting?

PCB manufacturers

● JLCPCB https://jlcpcb.com● Seeed Studio https://www.seeedstudio.io/fusion_pcb.html● PCBWay https://www.pcbway.com● OSHPARK https://oshpark.com● Micron-20 Ltd (Bulgaria) https://micron20.com/en