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2. Computer Aided design

This week i used a couple of 2D and 3D CAD (Computer-aided Design) tools and sketched out my final project.
The screenshots and videos i took of the process can take up quite a bit of space so i added a section showing you how to capture and compress them.

3D design in Autodesk Fusion

Autodesk Fusion, previously known as Fusion 360, is a commercial CAD, CAM (Computer-aided manufacturing) and CAE (Computer-aided engineering) tool with built in electronics design, rendering, animation and simulation features as well as support for community made extensions. This program is incredibly powerful and has been my daily driver ever since i got my first 3D printer in 2018. Thankfully Autodesk offers a slightly less feature rich version for personal, non commercial use completely for free. I feel like a salesperson saying this but i really do highly recommend trying it out. Here you can sign up for your own license free of charge.

Setup

  • upon first login you will be asked to create a team or join an existing one, which functions as your personal cloud

  • if you only use Fusion for personal projects go ahead and create your own team

  • on the left side of your screen you should now see the root directory of your team, here you can create new projects

  • you enter a project by double clicking it

  • here you can create folders and subfolders to your heart’s content

  • a new untitled design should already be open by default and take up most of your screen

  • if you want to hide your project and folder browser click on the X at its top right

  • the grid in the middle of your screen should now have even more real estate and maybe (if you are like me) hurt your eyes a little

  • let’s change that by heading to the bottom middle of the screen where you will find the Display settings

  • in the environment menu select the setting that suits you the most, i went with River Rubicon

  • next check if scrolling your mousewheel zooms in the right direction

  • i think we can all agree that scrolling up means zooming in right? …right?

  • if you feel that it doesn’t, click on the avatar in the top right corner of your screen and go to Preferences

  • click on the General tab and scroll all the way down to check the Reverse zoom direction box, then hit Apply

  • i personally find the grid quite distracting when in 3D view so i disabled it

  • right next to the Display settings you can finde the Grid and Snaps menu, where you can untick the Layout grid checkbox

  • enough setup for now, let’s get started with actually constructing a model 👇

Constructing a basic 3D model

The basic process of constructing 3D models in Fusion starts with a 2D sketch.

  • for starters let’s make the origin planes visible by clicking on the eye icon to the left of the Origin folder in the top left corner

  • now we can right click on one of the planes that just showed up in the center of our screen (for now it doesn’t really matter which one you click on)

  • select Create Sketch and get jumpscared by the return of the grid

  • in the sketch view it is actually quite useful but comes with its own little annoying bits such as snapping

  • basically this setting lets you snap points of your drawings to the grid which in the beginning might seem like a neat feature but it will get annoying quite quickly

  • i’ll leave the choice up to you but if you want to get rid of the grid simply uncheck Snap to grid

  • you can find all the basic construction commands in the top left corner via the CREATE dropdown

  • i highly recommend pressing S though to bring up the Shortcuts/Search menu

  • here you can search for commands and pin them to the shortcut menu for quick access

  • before using any command you should know that in Fusion most of them work by clicking on a start and an end point, holding down the mouse button and dragging it may have different effects

  • an example for this would be the line tool, click and release for the start point, click and release for the end point

  • click and release for the start point, click and drag after that to create an arc

  • let’s start with a Center Rectangle

  • as the name implies, you create a rectangle by defining its center point followed by dimensioning its sides

  • after clicking the spot where you want the center of your rectangle to be you can move your cursor a little and should see two boxes for the dimensions pop up

  • you can switch between them by pressing TAB on your keyboard

  • you don’t necessarily need to worry about entering the right dimensions right now, you can change them afterwards if you feel like it

  • i typed 20 into both boxes to create the following square

  • notice how the cursor still has the icon of the last used command next to it, which means that you can keep placing more Center Rectangles

  • to exit a command simply press Esc on your keyboard

  • double click the dimension (highlighted in green) you want to change and the box should reappear

  • if you want any dimensions to be the same you can double click one of them to show the box, then click on the other one to link them

  • now if you change the driving dimension the other one changes with it

  • the same result can be achieved with constraints

  • first remove one of the dimensions by clicking on it and pressing Del

  • navigate to the CONSTRAINTS dropdown and select Equal

  • now click on the two lines you want to be of equal length

  • constraints work like commands in that you need to press Esc in order to exit them

  • you can learn more about the different types of constraints in the Fusion Documentation

  • i still have one more of them to show you though

  • let’s draw a Center Diameter Circle

  • notice how i placed it outside of the square and didn’t give it a size on purpose

  • by pressing D on your keyboard you enter the Sketch Dimension tool which is normally found at the bottom of the CREATE dropdown menu

  • click on the circle, move your mouse and click again to show the dimension box

  • for now the circle is still floating outside of the square, but we are about to change that with the Coincident constraint

  • select the constraint, click on the center point of the circle followed by the center point of the square to create something like this

  • that looks good for now so we can click on the green check mark symbol in the top right labeled FINISH SKETCH

  • since we are now back in the 3D environment, the CREATE dropdown menu has different commands to offer which you can learn more about here

  • press E or select the extrude command from the dropdown menu

  • click on the inside of the square (highlighted in blue) and type a height value into the box that just popped up

  • i typed in 30mm and got this

  • head to the MODIFY dropdown menu in the top middle of your screen and open the Change Parameters command

  • here you can find the dimensions of the square and circle, try changing them by double clicking and see how the cube reacts

  • i also want to show you the timeline, a special feature found at the bottom of your screen

  • here all 3D commands are recorded and can be altered at a later time

  • to do that simply double click the icon of the command you want to edit and Fusion takes you back in time to the point where you used the command

  • after changing values in an earlier command Fusion recalculates the model accounting for the new values

  • here i changed the height value for the extrusion command by setting it to d1, which is the parameter used to describe the dimensions of the initial square

  • as a result i will always have a perfect cube, even after changing the square, neat right?

  • you can find the download of my example_cube.f3d file at the bottom of this page

  • based on this knowledge i built a first few models of my final project, click here to check out the progress

2D design using Inkscape

When it comes to 2D design i definitely prefer the vector approach. Especially when talking about techincal drawings.
Have you ever looked at an image, zoomed in a little and noticed how blurry and pixelated it has become?

This happens because these images are made exactly out of that: pixels Now imagine an image where you can zoom in indefinitely without losing any kind of accuracy That’s where vector graphics such as SVG files come in

Let me show you how to create those in Inkscape 👇

  • first up install the program as usual and open a new document

  • click on the rectangle tool or press R, click and drag your cursor to create a rectangle

  • on the right side of your screen you should find the “Fill and Stroke” window

    • if it is hidden drag these three dots to the left

  • in the Stroke paint menu select Flat color

  • you can change the width of the rectangle’s outline in the Stroke style menu

  • lastly select No paint in the Fill menu

  • the next step is to give your rectangle accurate dimensions

  • click on the Selector tool or press S and click on the rectangle

  • at the top of your screen you should find four boxes labeled X and Y for the selected shape’s position and W and H for its width and height

  • remember to select your preferred units in the dropdown menu to the right of the height box

  • i went with the following:

  • next order of business is putting a circle in the middle of our square

  • to do that select the Ellipse/Arc tool or press E on your keyboard

  • treat it the same way as the rectangle when going through the Fill and Stroke menu

  • i created a circle with a diameter of 10mm but the positioning is off

  • while we could simpy change the X and Y position, if we choose to resize the rectangle the circle would be misaligned again

  • at the top of your screen click on Object, at the very bottom of this menu you will find Align and Distribute

  • clicking this or hitting Shift + CTRL + A on your keyboard opens a new menu on the right next to Fill and Stroke

  • change Relative to: to Last selected and click on the circle

  • while holding Shift click on the square

  • directly below the Relative to: dropdown are a few icons, click on both Center on vertical and horizontal axis

  • now that both shapes are properly aligned we can select them both at the same time and hit CTRL + G to group them

  • this will make one object out of them meaning we can drag and scale to our heart’s content and they would never fall out of alignment

  • notice how far i can zoom in on the circle without any sign of loss of accuracy

  • all there is left to do is save the drawing as an .svg file

I have teased it with the first screenshot of Mr.Krabs’ claw, you can use Inkscape to trace the outlines of your pictures and turn them into paths

  • to do that you need to first load up an image and click on it with the selector tool

  • next head all the way to the top of your screen into the Path dropdown menu to select Trace Bitmap

  • a new window should pop up on the right where you can play around with the settings, just always look at the preview

  • in the case of Mr.Krabs’ claw i could actually have went with Multicolor so Inkscape would have divided the colors into zones or layers, but i just wanted to show you the difference between the outline quality

  • when you are satisfied with what you see in the preview window simply hit Apply

  • the generated path should now be placed over the image, so you need to move it but that is pretty much it

Capturing and editing videos and screenshots

OBS Studio introduction

  • OBS which stands for Open Broadcaster Software is a free and open source tool for video recording and live streaming, you can download it right here

  • to set up OBS Studio you first need to add a Scene and a Source

  • for Source select Window Capture and set the Window to the program you want to take a video of

  • you can have multiple sources at once and toggle their visibility by clicking on the eye icon next to it

  • you can pull on the corners of the preview window to resize it

  • next head into the settings, go to Output and select where you want your recordings to be saved as well as what format they will be in (i opted for .mkv)

  • after that you can open the video settings and adjust the output resolution to something smaller, that way you might save a step when cutting your videos later (i however set it to the same as the base resolution to have more control over it later)

  • hit apply and you are all set up, you can now Start Recording

  • don’t forget to stop recording when you are done, your hard drive will thank you

Editing videos with LosslessCut and Handbrake

  • LosslessCut is an awesome open source tool based on ffmpeg, you can find it here on GitHub

  • the purpose of LosslessCut is to quickly and easily cut your videos without losing out on quality

  • usually video editing software reencodes videos after cutting which has a sizable impact on quality, LosslessCut however pretty much stitches together the raw data

  • installation consists of unpacking a .zip file at your preferred location, unfortunately that way the program will not be added to the start menu automatically so it might be a good idea to pin it to your task bar if you plan on using it frequently

  • you can import a video by simply dragging and dropping it in the center of the window

  • toggle on the advanced view, then head to the settings and enable Show advanced settings scroll further down, disable Keyframe cut mode to have better precision over where your cuts are placed and make sure to enable Smart cut otherwise there may be some funkyness with keyframes

  • next you can disable the audio track

  • choose where you want to place your first cut on the timeline, click on Split segment at cursor followed by Remove segment 1

  • repeat these steps for the following cuts but make sure you remove the correct segment by clicking into it first

  • now click on the blue Export button in the bottom right corner, feel free to copy my settings

  • click Export again and you should have a nicely cut video that we can bring into Handbrake

  • Handbrake is yet another open source tool to convert video files from any format into different ones

  • we are going to use it to scale down the resolution and change the framerate of our videos in order to reduce the file size

  • installation is business as usual

  • drag and drop your video into the box and you should be greeted with this view

  • the first thing i did was change the preset to Fast 576p25 then headed to the video settings where i changed the framerate to 15 FPS

  • after that i went into the audio settings and cleared all audio tracks

  • the last thing i did was to change the save location and name

  • then i simply hit the green Start Encode button and watched the program do its magic

  • with all these changes the file size went from nearly 9Mb to only 150Kb

Capturing and resizing Screenshots

  • Greenshot, a free and open source screenshot tool optimized for productivity is my program of choice in this matter

  • it is surprisingly simple to use once you are past some initial setup

  • once installed Greenshot should start with your operating system by default and appear in the hidden icons menu of your taskbar

  • clicking it once reveals some shortcuts to capture screenshots, as well as a help section and of course a preferences menu, click on the latter and you should see this window pop up

  • feels kind of weird taking screenshots of a screenshot tool with said screenshot tool

  • also sorry about the german nature of my keybinds, here is a quick translation guide because i don’t want to change my keyboard layout in Windows

Druck       =   PrtSc
Strg        =   Ctrl
Umschalt    =   Shift
Alt         =   actually drawing a blank on this...

  • customize your keybinds to your liking and head to the Output menu where you can change the storage location, filename pattern and image format

  • i set my storage location to the images folder of the assignment i am currently working on and set the filename pattern to ${NUM} to automatically name my screenshots with an incrementing number

  • our next destination is the Destination menu where i unchecked Select destination dynamically and checked the box for Save directly (using preferred file output settings)

  • that is all the setup i needed so we can move on to resizing images which i do with the PowerToys Image Resizer

  • the Image Resizer tool should be enabled by default after installing PowerToys but if it is not, open up the PowerToys Dashboard and click on the tool’s toggle

  • maybe before resizing anything set up a local backup folder for your images, just to be safe

  • before i push all my changes and new images to my GitLab repo i simply select all of the new images and rightclick one of them to select Resize with Image Resizer

  • in the small window that just popped up i select the small preset and check all the boxes

  • after that i hit the Resize button and see how much space i save

Other tools to consider

  • it is always a good idea to think about other options

  • initially i thought about using Nvidia Shadowplay to capture my videos but i didn’t want to recommend software that only users of Nvidia’s GPUs could use

  • for now i will use it as a backup so if i mess up hitting record in OBS i can save the last 3 minutes of stuff shown on my screen with Shadowplay which is pretty nice

  • in the screenshot department the preinstalled Snipping Tool is quite useful

  • i mostly use it in those weird moments where i want to take a screenshot of only a small section of my screen, which i usually do via Greenshot by pressing ALT + PrtSc, but hitting any button besides PrtSc would cause unwanted effects in the software i am capturing (looking at you, Fusion)

  • that way the screenshot is only stored on the clipboard, so i have to paste it into something like MSPaint in order to save it properly

Downloads

Fusion Example Cube

Inkscape Example Square