Workshops

Table of Contents

Notes taken during workshops held by other FabAcademy people, aside the main lecture on wednesdays.

Blender

Shortcuts

syntax

  • a b: a and b pressed sequentially or depending on the context one symbol (such as “right click”)
  • a + b: a and b pressed simultaneously
  • a, b, c: alternative commands to achieve the similar thing
  • a b+c: a and after that b and simultaneously

menus

  • t: toolpanel
  • n: numerical panel
  • shift+a: add menu, search for objects, meshes etc. and add them
  • f3: do anything panel

general

  • right click: cancel
  • +, -: count up or down numbers

selection (normal mode)

  • shift+select: select multiple objects where the last object you selected is “active”.
  • aa: deselect everything
  • c: circle for selecting
  • …: change select modes
  • : only show what you selected
  • tab: switch to edit mode
  • l: select connected vertices
  • ctrl+i: invert selection

edit mode:

  • e: extrude
  • sel e ent s e: extrude from plane
  • x: delete face/vertice/edge
  • alt+click: select edge loops
  • ctrl+r: loop cut
  • alt+f: fill

animations:

  • i: set keyframe

navigation, basic editing

  • g: grab
  • r: rotate
  • s: scale
  • 1, 3, 7: change view
  • ctrl+1, ctrl+3, …: change view (other side)
  • g x: move along x direction
  • g y 1 ent: move selection along y axis by one unit
  • r z 45 enter: rotate along z axis by 45 deg
  • w: change way to select things
  • alt+g, alt+s, alt+r: clear correspondingly rotation, translation, scaling
  • r shift+z, g shift+z, …: apply operation in plane (here z plane)

TODO: check repairing 3d scans for missing shortcuts to add here

Tricks

  • transform edge loop while not moving one vertice of it:
    • move cursor to vertice that is not to be moved
    • change transform center to 3d cursor
    • mark loop (alt+sel)
    • transform

Workshop 1

preparation

  • check ferdis blender tutorial website
  • check 2025 page of week 2 of ilmenau fablab. there is a link
  • there is additional stuff there
  • we are gonna learn many kb shortcuts
  • do you have a numpad?o
    • if not: “emulate numpad”
  • also what is not keymap
    • keymap: frame selected
    • 3d vie, it says numpad colon. if you click on it you can just take normal colon. (with colon he means dot)
    • next one: matter of taste: zoom to mouse position?
  • use a mouse
  • a space mouse is nice. dont necessary

navigation

  • 3 most important things:
    • zoom, orbit, pan
  • windows: there are 4 windows. every window has a dropdown. mostly on left upper corner. if you click it it gives you a choice of many other window types
    • 3d view
    • outliner
    • you can split, join etc windows
    • even more windowing stuff.
    • the normal layout is also ok.
    • today just basics
    • just be aware that you can do many fancy things with your windows
    • you can take a blender window and extract it to a new “real” window e.g. for putting it on a different screen
    • most windows have side bars. you can hide it and you can extend it.
  • shortcuts intro
    • toolpanel: t
    • numerical panel: n
    • blender knows where your mouse button is. depending on in which window your mouse button is, there are different shortcuts. -> if you press a shortcut and nothing happens, check where your mouse button is
    • you can change shortcuts by left clicking on some option and click “change shortcut”

add and move objects

  • shift + a -> search for what you want to add
  • in general: if you right click: you cancel
  • add a cone
  • add torus
  • after adding it there is a bar at the bottom
  • add a monkey
  • now we wanna stack on top of each other
  • hit btns 1, 3, 7: change view
  • scaling mesh: s
  • for more precise control: move mouse away and then press s. then its more fine-grained
  • rotate monkey
  • torus is faceted. if you want to get rid of it: righ tclick: shade smooth. does not change anything of the geometry. just changes the normal of the faces. it will look as faceted in the rendering. it is just a visual thing.
  • this however looks weird on the cylinder, because it also “rounds” the bottom edge. therefore, you choose “smooth outer” with the cylinder
  • g: grap -> you can move
  • g, x -> move along x direction
  • g, y, 1, enter -> move cube along y axis by 1 unit
  • r, z, 45, enter -> rotate along z axis by 45 degrees
  • w -> change way to select things
  • if you hit alt, g, it lclears rotation, alt s clears scale, alt r clears rotation
  • g/r/z, shift, z -> move in the xy plane

selecting stuff

  • shift, select: 2 shades of orange. always the last object you seleted is the “active ones”.
  • aa: deselect everything
  • c: circle for selecting
  • select modes: vertex or edge select mode. you can shift click on them to activate multiple ones.

edit mode: tab

  • you can select faces, points, edges, etc etc and move, rotate, scale them
  • select face
  • e: extrude
  • e, right click, scale -> you can scale the plane itself
  • you can go crazy with extrusions
  • then, do subdivision surface modifier and smooth surface

parametric design

  • do further reading on “hooks”

do we have a history?

  • there are geometry nodes in blender
  • you can also work with a modifyer stack.
  • in order to ago wtih modifiers

“do anything” panel: f3

  • all commands are available there.

modifiers

  • subdivision surface

saving files: + and - keys count numbers up and down

  • when you save and change the file, blender creates backups itself.
  • higher number means older
  • you can change how many backup files are created
  • every number blender says is actually millimeters. you just ignore all of this and you know it is millimeters. you just scale it by factor of 1 when exporting everything.

camera settings - when you scale meshes really big, it might be that your camera is “clipping”. you can change that using the camera settings

Workshop 2 (Week 3)

shotcuts - different views - z wireframe - gz move selected object in z direction - gzz move selected object in relative direction of selected object - - shift s open snap menu - change curser to world origin - shift a add things

  • 3 point lighting
  • see wikipedia
  • add spotlight
  • turn on / off shadow of normal light
  • small light is our backlight
  • n -> open numerical panel -> view
    • lock camera to view. you can move your camera in a more handy way
  • now, we want to render
  • making cube blue
    • material menu (right side, just as with lamp)
    • change color
    • now we dont see it in the editor so -> menu top right of 3d viewport -> viewport shading
  • you can also name your materials, there even is a shortcut for autonaming materials
  • making monkey head metallic
    • material menu
    • metalic -> 1, roughness -> 0
    • you can change the environment that is rendered in viewport 3d menu -> viewport shading -> change environment
  • when rendered, metallic heid of monkey does not look really refelecting. we dont have an environment defined for rendering.
  • excourse: hdri images. people take huge images multiple times with different exposure times and combine them so they cover a high dynamic range
  • there are different types of how to store a 360deg image:
    • mirror ball
    • equirectangular.
  • check paul debevec: uffizi probe
  • there you can download nice hdri images, do that
    • we choose some mirror balls.
  • we want to use that as a background: “world” in properties menu. click on yellow dot of “color”. environment texture. choose hdr file you downloaded
  • choose “mirror ball”
  • viewport menu: viewport shading: toggle on scene world
  • websites for textures and environment hdri images: https://polyhaven.com/

animation

  • i set keyframe
  • move in timeline, change parameters, set keyframe,
  • go to graph editor
  • ctrl, mid mouse, zoom: horizontal scale
  • go to “output” in property menu, there you can see the animation end
  • in graph editor: change rotation line to be a linear transition

textures

  • keyword: uv map. texture of a 3d object.
  • in shader editor: add checker texture. this is a procedural texture
  • materials: https://blendermarket.com/
  • addon for assets: blenderkit: https://www.blenderkit.com/
  • uv editor
    • uv editor: go to edit mode in 3d viewer, then you can see the grid of the selected object in the uv editor. however, the uv editor is just for editing the uv map.
    • for actuaally seettting the image as a texture of the cube, you go to materials

windows

  • to the right side, right click, horizontal split

Repairing Scans

  • most importantly for 3d print:
    • models need to be good
    • non-manifold: definition is very long. we interest: we want to have a volume. if you have something that is no non-manifold than you have a volume model. this is what we want. (mathematically not really correct)
    • non-manifold points are merged by slicer but it can happen that there is then bullshit coming out of that.
      • you can see when you slice: this is why slowly scrolling through layers and checking if first layer is good
    • remove manifolds (see blender)
    • remove non-manifolds
      • there are
  • most 3d scans you cannot repair automatically
  • what you do when you have non-manifolds
    • a little bit like häkeln
    • \ only show what you selected
    • edit mode -> vertex select mode -> select -> select all by trait -> non manifold
    • remove non-manifold point
      • x delete face/vertice/edge
    • remove other points and faces that are useless, that you maybe dont see from outside.
    • ctrl 2: apply subdivision surface
    • select edge loops: alt click
    • shortcut o (proportional editing). choose
    • the resulting hole can be repaired.:
      • select edge loops: alt click
    • press f to fill
  • suzanne is non-manifold.
  • ferdi fixes:
    • hide eyes
    • select non-manifold points
    • extrude scale
    • transform to circle
    • still gewölbt against y axis
    • scale against y: 0
    • ctrl r loop cut

Shaders

Mesh to NURBS

  • nurbs: non-uniform rational b-spline
  • alles was in fusion is is nurbs
  • alles was in blender ist ist polygone (kann auch nurbs aber das ist scheiße)
  • wenn du nen mesh hast, gibts nen trick, wie man den umwandeln kann in einen nurbs
    • was ferdi etzt sagt ist übelst viel wert und wenig leute finden das.
    • da gibts was auf github: https://github.com/wjakob/instant-meshes
    • damit kannst du deinen mesh in blender so retopologisieren dass er nur aus quadraten besteht (keine dreiecke)
    • und dann kannst du das in fusion als nurbs oder als shape importieren.
    • der vorteil ist: meshes will man nicht fräsen. die fräse will dann jedes dreieck abfahren. dafür gibts aber splines. aber die fräse hat immer eine richtung. du kannst keine konturen erkennen. bei splines ist das nicht so. du kannst so also einen schöneren gcode generieren.
    • was ferdi über fusion gesagt hat gilt auch für freecad
    • was freecad nicht hat: multiaxiales zeug. da gibts aber was.

Inkscape

  • if use for lasercutting: check lasercutter max size. for us (see wiki): figure out how big the cutting surface is. 82.9cm x 62.5cm x 17.5cm -> round to 800mm x 600mm
  • adjust document size in inkscape.
  • draw a ronud circle: circle tool plus ctrl button
  • color choose at bottom
  • shift click: determine border color
  • … (did not continue video due to time)
  • personal hints by ferdi from now
  • duplicate strg d
  • shift ctrl scale from center and keep eproportion
  • linienstärke wird mitskaliert. kann man einstellen
  • node tool: change shapes.
    • behaves differentley depending on if you are inside or outside the shape
  • object: circle, text, rectangle, star, spiral etc.
  • path: is another concept. typical bezier spline
    • you can add more nodes to paths using the plus sign
    • ctrl click changes node type
      • node types are listed in menu above
    • boolean operations: between paths.
      • union, difference, intersection
      • ctrl -, ctr +, etc
  • group: ctr g
  • ungroup: ctrl shift g
  • create outline:
    • duplicate shape
    • path -> dynamic offset
    • this can also be used for:
      • you want to cut something consisting of different parts (would fall apart)
      • create an outline. cut everything between outline and different parts -> have a “negative” cut
  • ornamente
    • search for ornament black white browser
    • insert to inkscape
    • convert it to vector graphic
    • threshold 0.85 is nice value
  • you can define dimensions using X and Y fields
  • cloning things
    • clone tool in inkscape
    • allows for having different colors of the clones as well as different rotation/size etc.
  • create qr codes (extensions -> render -> qr code)
  • extensions -> gcodetools
  • trick:
    • edit -> xml editor
    • you can select something ni inkscape and look at the text. so you see the source code of the svg.
    • say you want to check the color of something. so copiy the color.
    • then go in inkscape: ctrl f, and then search for the color. then, everything wit hthat color is selected.
    • “select everything blue”
  • you can show only lines:
    • view -> view mode -> countour lines
  • cloning
    • draw rectangle, give it a color. fill it with a gradient.
    • draw other random shapes in it, like a star. choose question mark for the color.
    • edit “tiled clones”: 6x6 -> nachzeichnen -> take the color that is below it, create 6x6 clones.
    • adds multiple shapes of different colors
    • this also works with a bitmap instead of a shape wtih a gradient
    • you can do halftone with that.
  • create one tiled image out of multiple ones
    • open inkscape and drag images so that they form a tiled image
    • overhanging image parts can be removed by: drawing rectangle which includes exactly that area that is to be the final image, select object -> clip -> set clip

GIMP

  • blackwhite vector graphic aesthetic:
    • monochrome
    • contrast high, bright low
    • apply gaussian blur
    • repeat -> use inkscape to create vector graphic from it

FreeCAD / CAD

Shortcuts

  • Ctrl + Tab: switching tabs
  • Alt: disable auto constraints

part design:

  • g r: add rectangle
  • g l: add line
  • g c: add circle
  • g a: add arc

inside spreadsheet editor

  • alt+c: go in content field
  • alt+a: go in alias field

inside dimensioning tool

  • =: open formula editor

Hints

  • Preferences -> Navigation -> Display: mess around with rotation adjustments.
  • Babken: Quick PSA to anyone using FreeCAD: I don’t know if it’s a v1.0 thing or a less recent bug but I’ve been going over a sketch I did last year and it’s been incredibly slow to deal with. I’ve boiled down the problem to the “expression” calculation on constraints. it doesn’t seem to matter the contents of the field, even if it’s just a fixed value and not a local calculation or reference to a spreadsheet. As long as it’s set any action on the sketch takes way too long to the point I’m redoing all of them. Granted it was a weird sketch with too many lines and constraints o with some luck it’s just something messed up on my install/computer. But if you run into a ridiculously slow sketch check the valued constraints and if you can get away with it set the value in the basic text box.
    • Svavar: I’ve made this mistake in SolidWorks, Inventor, Fusion and FreeCAD and their sketch solvers all become slow when there are lots of lines and constraints in a single sketch. Parameters and equations also slow down the solver, but you can have many parameters in FreeCAD if the model is well defined. A CAD best practice is to make each sketch simple, and then add more simple sketches to add detail. Avoid fillets and arrays in sketches, and use 3D features instead (Fusion also recommends this). I know you’re not a newbie, but sometimes it’s good to be reminded of these things.
  • you always want to keep your sketches as easy as possible!
  • build sketches hierarchically

Arduino

  • led: inside the led: the big part is plus (plus is more)
  • how do clocks work?
    • quartz crystals. if you hit it, they produce a voltage. if you apply a voltage to them, they oscillate