There is a lot to say about 3D modeling and there are a lot of best practices out there around how you should go about making a model. Most of this has to do with animating the models afterwards, which is something we will never have to do. This means we can use a more hacky approuch that will give use a result the slicing software will be happy with as long as we stick to 3 easy rules. Before we get into the rules, lets get some terminology out of the way.
- A polygon is a point in 3d space
- An edge is a line connecting 2 polygons
- A face connects 3 or more edges into surface area for your mesh
- A mesh is the skin of your model
Now the rules
- No intersecting edges/faces
- No floating polygons/edges/faces
- No edges without faces (holes in the mesh)
The easiest type of shape to make is a logo because it usually consists of a base shape (rectangle/cicle/) and shape we can extrude from or indent into the base shape. 24 days doesn't seem to have an oficial logo, so lets make a simple square with 24 inside. Lets get started. When we start a new project in blender we are presented with a 2x2x2 cube. Lets edit it to be 40% less high
- Select it
<Right Mouse Button> - enter edit mode
<TAB> - switch to face selection mode
<CTRL+TAB> <3>Or click the corresponding icon on the bar below your viewport - select the top face
- drag the blue (Z axis) arrow down untill you see -0.8 in the lower left where your toolbar was. Or you can do it precisly:
- activate move transform
<G> - restrict to Z axis
<Z> <-0.8>You should see the shape transform as you type<Enter>to confirm or<Esc>to cancel Next lets make the base shape a bit concave for aestetic puposes- with the top face still selected
- scale the edges down a bit. You can do this with the pointers, but to uniformly scale acros multiple axises (???axi???) its easier to do it the precise way:
- acivate scale transform
<S> - we dont need to restrict here since edges only have 2 dimensions and we want to scale over x and y
<0.9> <Enter>
Next up is the part we want to indent or extrude from the main shape. This is a bit trickier but if you have an svg of what you want to make, blender has a nice import tool that makes a polygon line for you. If not, you will have to aproximate it yourself. Luckily we can get the font used for 24 in svg format (https://www.onlinewebfonts.com/download/890c469d7dd06e5c5e22cd2ef499cfca) which we can open in Inkscape so it imports the font. Now we can make the svg file:
- create a new file
- new textArea, select the correct font, set it to a large size (1000) and type in "24"
- convert the text object to a path: menu,path,object to path or
<SHIFT+CTRL+C> - save the file
Back in blender
- exit edit mode
<TAB>(your whole object should now have a single orange outline instead of only having certain parts selected) <A>to deselect all- Menu, file, import, Scalable Vector Graphics (.svg), select your file If everything went right, you should see the flat 24 text appear somewhere in your viewport. And the object browser on the top right, should have a "curve" and "curve 001". To make it easier to recogize the different objects, rename to 2 and 4 (Right click in the object browsers, rename). Lets move our object more or less into the correct position, this way we create a better perspective to start extruding the 24 into 3d space.
- while staying in object mode (dont press
<TAB>) - select both 2 and 4, either in the viewport or in the object tree (shift for multiselect)
- to make it easier to scale and move, lets reset the origin point of the object to the center of its mass. and use the new origin points to set the pivor cursor
<CTRL+ALT+SHIFT+C>"origin to center of mass"- Set pivot point to average of the origin points
<SHIFT+S> <U> - Move the object more or less centered above the "cube" using the move arrows. Scale the object (
<S>move mouse) untill the 24 touches the sides. You can change your camera angle to top view<Numbpad 7>and active wireframe rendering mode<Z>to help you better position everything in the x-y axis and then move your camera to front view <numpad 1> to position on the Z axis. Dont fret to much about perfect positioning just yet, we will adjust things a bit later anyway. (if you don't have a numpad you can emulate it:menu > file > preferences > input tab > simulate numpad)
If the 24 is in the wrong orientation:
- activate rotation
<R> - lock to the Z axis
<Z> - enter
<90>or<-90>depending on the current orientation
Alright lets make 24 an actual 3d shape
- deactive wireframe mode if you are still in it
<Z> - Swap to top view
<Numpad 7> - While in object mode,
<ALT+C>"Mesh from curve..." - select shape 2
- enter edit node
<TAB> - select everything
<A> - swap to front view
<Numpad 1> - Extrude slightly
<E> <0.2> <ENTER> - Deselect all
<A> - Exit edit Mode
<TAB> - Select shape 4 (trough the object browser) and repeat the last few steps
<TAB> <A> <E> <0.2> <ENTER> <A> <TAB>
While in object mode, move the 24 (remember you can select multiple object in the browser or viewport by holding down <SHIFT>) into position by dragging the blue arrow down untill the shapes are 90% into our base shape
Making the indentation
- While in object mode, select the base shape by right clicking on it.
- Under the object browser should be an onther window with a lot of tabs (the properties window) in this window there is an icon of a wrench (object modifiers), click on it
- Click on add Modifier and chose Boolean
- Click inside the object box and select shape 2
- Click on the operation dropdown and choose "Difference"
- DO NOT CLICK APPLY
- Add another modifier and repeat for shape 4
- AGAIN, DO NOT CLICK APPLY
To see the result, hide the 2 and 4 from the viewport by click on the eye icon next to them in the object browser. If you angle your camera a bit, you should now see the indentation of 24 into our base shape You can now adjust the position of the indentation by moving the 24 shapes around. When you are happy, click apply on both modifiers while the base shape is selected.
And there you have a it, a very basic icecube/chocolate shape with the 24 days logo in it.
PS: Blender supports exporting to STL files (File-export-Stl) and this is a file format most (if not all) slicing software supports, when you select a single object, only that object is exported. Happy printing!