In case you weren’t aware, having a 3D printer is nothing like owning a real-life star trek replicator. For one, replicators are normally found on Federation starships and not hype trains. Secondly, the details of how replicated objects are created in the 24th century is an issue completely left unexplored by TNG, and DS9, and only a minor plot point in a few Voyager episodes. Of the most likely possibilities, though, it appears replicated objects are either initially created by ‘scanning’ them with a teleporter, or commanding the ship’s computer to conjure something out of the hologrid.
No, with your own 3D printer, if you want a special object you actually have to design it yourself. Without a holodeck. using your hands to step a mouse and keyboard. Savages.
This series of ‘Making a Thing’ tutorials aims to fix that. With this post, we’re taking a look at Blender, an remarkable 3D modeling and animation package.
Because we still haven’t figured out the best way to combine multiple blog articles together as a single resource − we’re working on that, though − here’s the links to the previous “Making a Thing” posts:
OpenSCAD
AutoCAD part I
AutoCAD part II
This list is sure to grow thanks to your suggestions on what 3D modeling software to feature, but for now let’s make a thing in Blender.
Our Thing
To the ideal is the part we’ll be creating in Blender. just like the OpenSCAD and AutoCAD tutorials, we’re using the same object, a odd switch base thing taken from a 90-year-old book on drafting. You can click to embiggen that.
A Word about Blender
Blender is created as a 3D animation suite. You know the old mid-90s Pixar short films? You can make those with Blender easily. using Blender to design a small object to send to a 3D printer is like using a bulldozer to build a sand castle. You can do it, but it’s overkill.
Ideally, Blender must be used for objects that aren’t mechanical in nature. If you’re creating a gearbox for an RC car, don’t use Blender. If you’re making a replica of the Antikythera mechanism, don’t use Blender. If, however, you’re creating something a lot more sculptural – a Pietà, for instance – Blender is a great tool.
Despite Blender being complete overkill for this basic part, and the fact Blender isn’t well suited for creating mechanical parts anyway, a lot of people asked for a Blender tutorial. Who am I to argue with the commentors on Hackaday?
Starter opp
Installing Blender is left as an exercise to the reader. Do that here. When you first start Blender you’ll see the following screen that includes a cube, a cam (the pyramid-looking thing), and lamp. This is the default starting screen and we don’t need any of these objects. On your ideal hand toolbar, go to your Scene tab (at the top of the toolbar), right-click the cube, camera, and lamp, and delete them.
Meshes
Now that we have a blank canvas, we can start creating our part. considering that this part of this tutorial is already halfway done, we’re only going to design the ‘washer’ part of our thing – the circle with a 3/8″ slot.
Instead of editing solids like OpenSCAD and AutoCAD, Blender does things entirely differently. It uses meshes, or collections of vertices (points in 3D space), edges (lines between two vertices), and faces (polygons made of edges) to define an object. We can start building our thing by making a cylinder mesh. From the top menu bar, select add -> mesh -> Cylinder and left click. A cylinder will appear at coordinates 0,0,0 in your scene.
After you’ve done this, you’ll see an ‘Add Cylinder’ window on your left hand toolbar. This window allows you to edit the number of vertices, the radius, and the depth of the cylinder. now is a good of a time as any to start editing our part, so make the radius of the cylinder 1.1875 (one half of the 2 3/8″ diameter of our part), and the depth 0.4375.
By the way, yes, I am regretting using a part from a 100-year-old drafting textbook ideal about now.
Here’s what we end up with:
That’s making a very primitive object in Blender. To make anything useful, though, we need to go into edit mode.
At the bottom of your Blender window, you’ll find a menu that will change how you can interact with Blender. Right now we’re in object mode, which allows for the creation of meshes, surfaces, cameras, and lamps. To edit our object we need to be in…. redigeringsmodus. click on the little pull-down menu and change over. Doing this allows us to edit all the vertices, edges, and faces of our object. Here’s the cylinder we just created with all these selected:
Hit the ‘A’ crucial on your keyboard to deselect everything. now the cylinder is gray.
Now we need to put a hole in this part of our thing. If we were modeling with solids, we would simply create another cylinder, smaller than the one we have now, and subtract it from our current model. We’re not working with solids, though; we need to create the faces of our objects without boolsk operasjoner.
For å lage hullet i denne delen av vår ting, velg toppen av sylinderens øverste ansikt og med ALT + F-tastaturkombinasjonen, velg INSET FACES med verktøyet Idea Pop Up Thingy. Insetting et ansikt tillater oss å lage en ny topp og bunn for denne sylinderen som vil svare til det nøyaktige hullet vi trenger.
Når du aktiverer innsatsen på innsiden Faces, er størrelsen på hullet du lager, avhengig av hvor langt du trekker musen din; Ikke bra for noe vi skaper fra nøyaktige målinger. På venstre verktøylinje kan du imidlertid gå inn i tykkelsen vi ønsker.
Slik går matematikken, hvis du lurer på. “Cylinderen” av vår side er 2 3/8 “i diameter, og vi vil ha et 1” diameterhull i midten. Trekk 1 tomme fra 2,375 og du får 1,375. Tatt i betraktning at tykkelsen på dette ansiktet er i virkeligheten en radius, dele 1.375 av to, og du får nummeret vi ønsker. Jeg hater virkelig desimal tommer.
Etter å ha slettet den øverste delen av hullet vårt, flip delen over i blender og gjør det samme til det andre sirkulære ansiktet av vår side. Du vil ende opp med noe slikt:
Nå er alt vi trenger å gjøre, bli med på topp- og bunnflatene.
På verktøylinjen der du valgte Redigeringsmodus, ser du et sett med tre knapper. Den ene er en terning med et toppunktsmessig uthevet, en er en kube med en kant valgt, og den andre er en kube med et valgt ansikt. Noen ideer hva disse knappene gjør?
I stedet for individuelt å velge hver av disse kantene på innsiden av vår side og skape 36 individuelle ansikter, skal vi gjøre noe mye enklere. Hold nede Alt-tasten, velg en av innsiden kantene med den ideelle museknappen. Dette muliggjør utvalg av kantløyfe. Nå, på verktøylinjen Mesh Tools (venstre side), trykk ekstruder og trykker på ‘Z’ avgjørende på tastaturet for å låse musens inngang til en bevegelsesakse.
Igjen på den ideelle verktøylinjen, ser du en trio av bokser merket ‘vektor’. Dette er hvor langt blenderen vil ekstrudere vår …. ekstrudering i X, Y og Z-aksen. Vi ønsker å ekstrudere denne kanten 7/16 “(eller 0,4375 desimal tommer i den negative Z-retningen. Det er lett nok.
Her er det vi ender med når det er gjort. Ja, det tok meg tusen ord å beskrive hvordan man lager en vaskemaskin i blenderen.
Så hva lærte du bare?
Så langt som opprettelsen av vår ‘ting’ i blenderen, fikk vi ikke veldig langt. Det er fortsatt flenser og hull og runde overs å gjøre, men dette er bare en del en av denne blenderopplæringen. Forhåpentligvis tjente dette som en god introduksjon til blenderens masker og redigerer disse nettas ansikter og kanter.
Se deg her igjen neste uke!