 Welcome to the LIDAR C3! Good evening everybody to the Franconian net.stage. We have the pleasure to introduce to you Flo from the Franconian subdivision Hexhoktum Korburg, who will introduce you to the basics of 3D construction with Blender mainly for 3D printing. This semi-workshop is beginner-friendly so everybody can follow easily. So have fun and now I give the floor to Flo. Hello to all of you. I'm Florian and I will tell you something about creating 3D models with Blender so you can then create them in the real world with a 3D printer. Originally I wanted to make this a workshop where you can ask questions and I answer them during the presentation but this will make the duration very unpredictable so I will instead try my best in the Q&A afterwards. If you have two monitors you can run Blender on one and directly construct in parallel to the talk. I have already tried to hold a version of this workshop for the hacker space I'm in and uploaded it. Please do not look it up. It's not that great and with an older Blender version. The equipment that I started with when I began 3D printing is a really old Pusa fused filament 3D printer and I assembled it from a building kit that I got as a birthday present. The 3D printer itself has quite a lot of parts that are 3D printed themselves like the joints and mountings of the frame. And the 3D models for all of these parts were also on a CD that came with the kit so I could print my own spare parts for the printer and that's great. And of course there are a lot of 3D models for all kinds of things out there on the internet which is also great. But I wanted to print my own designs. I wanted to slightly change some parts of the printer. I wanted to install a small PC cooling fan which needed an outlet that exactly fit to the printer hotend position and so on. So I needed a 3D construction program. And of course there are very good and very expensive solutions for all of that and of course there are also a few free ones but at the time I found an issue with every one of those that I tried. Until I tried Blender. And this is what I now know to use and that's what I can tell you about even if there exists maybe a better program in the meantime. But here's the thing. Blender is not a construction program. It's just so versatile that you can use it as one up to a certain extent. And it's free software and you don't need to be connected to the internet to use it and your models are yours. But now back to the workshop. You can see here what I recommend. If you haven't already you can still download and install Blender now. We will not start 3D modeling immediately. First there is some basics that I want to go over. Here are the basic steps from 3D model to printed plastic as I understand them. And I will start with the end product. We want a printed part. In this case the highlighted cooling fan outlet. And I will focus on fused filament printers which are most common and affordable at this time. The printer needs to know when and how to move its printing head and how much to heat the hotend and so on. And it gets this information by following the printing commands of a G-code file. Actually there is the printer's own firmware in between and some printers use SD card interfaces while others can be controlled via USB port and separate printing software. But this is basically how it works. The G-code file contains detailed commands of the printing process for its specific 3D model. And the G-code file is created with the slicer program. It cuts the 3D model into slices and it divides these slices into segments and pathways for the printer head to follow. Usually the 3D model has to have the SDL format for this. And here we are already with Blender because you can export your 3D models in the SDL file format with Blender. And with Blender you can create 3D models. So we are back on track. First let's get to the printer again because I have already used some words that some of you may not be familiar with. Here's a sketch of how a fused filament printer works. A feeder motor pulls in a plastic filament and pushes it into a metal nozzle. Its upper part must stay cold enough to keep the filament solid so it can seal off the molten filament. And this upper part is the cold end. The lower part is the hot end. It's heated and melts the plastic and pushes it out as a thin strip. The molten plastic sticks like hot glue onto the heated bed and to each other strip that was put down before, row after row. The plastic then cools down and solidifies until a whole flat area is filled out. And then the printer head is lifted up by one layer height and glues another layer onto the first layer. And this layer printing has some properties that you should consider during designing. I have encountered four main issues that are important to remember during designing. On the left there's always the picture of a bad example and to the right there is a picture of a good example. I used the 3D, the slicer software to make most of these pictures. First, adhesion. The printed part must have enough surface in contact with the heated bed or else it will break off during the print and that can end badly. And I learned that the hard way. Angle. The printer cannot print into thin air. It needs to either glue the plastic string onto another surface or bridge it from one end to another. So either glue it down or bridge it here from one end to another. And if you have these overhangs or completely round holes then at some point the plastic will fall down. Clearance. This is important if you have interface objects like screws or nuts that have to fit into your printed part. And of course you can also drill out holes afterwards or heat the metal part up and then melt it in. But it's best when everything fits as it should. Anisotropy. The printed parts do not have the same stability in all directions. There are always some imperfections between the layers and the parts will break most easily along the layer surface. The example shows the same part but printed in a different orientation. And here the layers have a large cross section. This would be good. And here the middle layers have a very small cross section and this is where the part will most likely break. All right, onto modeling. I'll start with a newly installed blender. And I will set it up the way I need it to construct things. The people who make blender software love to make changes to the user interface from version to version so what I am doing here only applies to blender version 2.91.0. Okay. We have started it. Now we click anywhere outside of this middle part. You can rotate by holding the middle mouse button and moving the mouse. You can zoom by using the mouse wheel. And then I activate the tool menu in the upper right. There is a little arrow. Then I press tap to enter object mode. Tap toggles between object and edit mode and you see in the upper left what mode you are in. In edit mode I set the global coordinates. So global is blue. I make my object translucent with x-ray. I activate normals. This is in the upper right here. Overlays go down to normals and click on the face normals and I make them 3 millimeters large. And then I activate quad view. This is under view area toggle quad view. And now we see our screen has split. In the upper left area you see the view from the z-axis downwards on the objects and in the lower left and the lower right view you see from the side. And here you still have your 3D view. And you can still use your middle mouse button to rotate. Okay, then there are units. So we go to scene properties. Here the cone shape. Select units. And I don't want metric, I want none. This way the distance numbers will be interpreted as millimeters when exporting to STL. And I find it easier to work with coordinates that are not broken into meters, centimeters and so on. And this would happen if you chose to use a unit system here. Now I delete the camera. I click it on in the scene collection and press delete. And I delete the light. And I save this as a template. So file. Save as template01. Save as. And this is a blender template that I can work with to construct things. This is how I want blender to be to be set up. Alright, now I overview over some tools in Blender. The most important one first, how do I undo what I just did? So Ctrl and Z. And you don't need to have this table in front of you during the workshop. This is a simple step, but maybe you want to take a screenshot. Okay, back to Blender. There are two main methods I use to create technical objects. One is adding and subtracting simple bodies, two from each other and the other is extrusion of a complex body from a 2D shape. And of course you can also combine these. And I will start with adding and subtraction. I will show you how to create a simple mounting board with four holes in it. I will actually print it in some version for a quadcopter in our hackerspace. So first I delete the cube or first I go into object mode with tap and select the cube and delete it by pressing delete. And then I create a cube. But I want its edges to be 45 mm long. So I go to add mesh cube. And here in the lower left you can change the properties of the cube and set the size to 45. I can zoom out with mouse wheel. And I will put the cube in the upper right corner of this coordinate view. So I set its location to 22.5 in the X direction and to 22.5 in the Y direction. And this will make it easier to check if I have the right dimensions for the cube so I can go into edit mode now. And if I now click one of the vertices here it must be in X coordinate 45. And it is, I can check this here, the X coordinate is 45. So this is correct. And I name it, I go back to object mode and I name it, what did I say, mounting plate. So this is what is going to be a mounting plate and not a cube so we need to flatten it. So I go into edit mode, tap and I select the lower four vertices. I can check that I have them in the 3D view and I will put their Z coordinate to 0 in the upper right here. And now it snaps up to 0 and I want my cube to be, or my mounting plate to be 3 mm thick so I do the same with the upper four vertices so I box select again by clicking and dragging and I set the upper vertices Z coordinate to 3. And I can move the view laterally by clicking shift and holding the middle mouse button and then dragging the mouse. So shift middle mouse button and then dragging. Okay, now we need holes in our mounting plate and this is where the Boolean modifier will come into action. So I need to create a cylinder object with the radius of the holes that I want and I remember the clearance rule so if I want to put in M3 screws with 3 mm diameter so with 1.5 mm radius I need a bigger hole I need a hole with 1.7 mm radius so I can be confident that I can put them in despite some position tolerance or printing imperfections or whatever. So I go into object mode with tap click into nothing and I add mesh cylinder I give it 24 vertices that's what I always use 24 or multiple of 24 for round objects or almost always use unless I have a good reason for it and then I give it a radius of 1.7 and I want it in I want its center to be 10 mm away from the edges of the mounting plate so I set its x location to 10 and its y location also to 10 and I set its depth to 20 mm it must be higher than the plate is thick ok and then I maybe want to also take out some cavities for an M3 nut and I can do that also so I go again to add mesh cylinder I give it 6 vertices because it's going to be a hexagonal nut and I give it a radius of what was it 3.4 and a depth of 6 and again the location of the screw so 10 in the x 10 in y and in this case 5 in z so I still have an overlap with my mounting plate and I want to name my parts so this is my M3 nut we double click them in the scenes collection and the other cylinder is my M3 screw ok now we could copy these objects and remove them one by one from the plate or from the mounting plate with the Boolean modifier but we will try not to be unnecessarily diligent here so first I will combine the two objects that I want to remove I make the I select the nut and make it invisible it will still be there but you cannot see it and then I select the screw and I go to the wrench symbol and I add the modifier Boolean and I want to make a union with this invisible nut so I click union and I select the object M3 nut now they are one object now it is added to my M3 screw and I want four holes in the mounting board not just one and I can use the symmetry of my mounting board for this and for this I will add an empty so I go to add empty just plain axis and I put it to location 22.5 22.5 I could still change the location here if I wanted to and I rename it center empty alright so I will now select my screw and I have already a modifier on it and I put on another modifier a mirror modifier and I want as mirror to project my empty, my center empty and here you can see it is already by default mirroring in X direction but I want also to mirror in Y direction now I am doing this and then I can make my screw invisible also click my mounting plate and add a modifier Boolean and this case difference is okay because I want to take away the screws and I select the screw and it is taken out of my mounting plate okay now I can save it to make sure save as and I can make a and I can export it as a STL and when exporting to STL you must make sure to click selection only so you must have your object selected and then you must select only so that you will only create an STL from this and not from all the other objects that are also in this file okay and that's it so we created objects, we have given them properties like size and position, we change the position and we use the Boolean modifier and the mirror modifier and I can now give you an overview over some modifiers these other modifiers I use for construction and some of them you have now seen okay now on to 2D extrusion I will first close this file and I will start again with the with the wait with our standard blender file that we have with the template that we have saved okay there are objects that are easier to create with the Boolean modifier as we all just did and there are other objects that are easier created with the 2D extrusion and the cooling fan nozzle that you saw in the second slide was one of these it was one of my first models and I would not do it exactly the same way now and I was thinking of what I might show that others might find useful and I thought of a cooling fan propeller that you can print and glue onto an electric motor shaft maybe more a thing for the summer but that's what it is okay now I need to create a 2D pattern for this fan I will start with inner hollow cylinder that holds the propeller blades so I go to object mode, I select my first cube and delete it and now I will create a circle so add mesh circle and I change the circle properties I give it 20 vertices and a radius of 1.785 and I will create another one but I will do this in edit mode so I select my circle, go to edit mode and add another circle and give it a radius of 4 and this way because I created it in edit mode it is still part of the same object as the first circle so I can create vertices of both at the same time now they are one object and these values derive from an actual electric motor shaft that I measured at some time and you would have to choose your own if you want to print this for yourself and now I will fill the area between these circles you can do this with the box selection so click and drag and then press F so you have one quarter and do this again and make sure that you do not overlap any of these points you can also select the points in a different way you can select one and then control left click another one and then shift left click an inner one and then control left click the corresponding one so you also have a one quarter selected and then press F and press F again for the last then we have our areas filled with faces ok and now we need to create two other circles I will zoom out here and they also need to be part of this object so this is still ok in edit mode so I go to add circle and I give it 100 vertices and the radius of 40 I will create another at circle with a radius of 39 and I again have to fill in the spaces of these I can do this with the clicking method control left click Alt I mean shift left click control left click and F or I can do it with the box selection but I must make sure that I do not select circles for this and if I shift and box select I will keep my selection and with F I create the face and again here box select shift box select shift box select F ok I have my four faces and they are all looking in the wrong direction so I now go face select here and I shift left click all the faces that I need to turn in the other direction and then I go to mesh where is it normals and flip and now they look upward and now we have the space that will contain the fan blades and I will now shape the 2D shape of one blade and then rotate multiply it so I will create another circle as a new object I will first again go back to vertex select and then top to go to object mode click into nothing add mesh circle a new object circle and this one will have 80 vertices and a radius of 26 and a Y position of 27 and now I switch to edit mode and add another circle radius is in this case 28 and Y position is 27 again ok with shift and middle mouse button you can drag the position of the screen shift middle mouse button and now I delete everything of this fan blade that I don't need so I will select what I don't need this is what I will keep so I must delete all the other things so I will box select and delete them delete the vertices box select delete vertices and the last one and now I will create square faces in this fan blade that I have here so I select the four vertices that create square and press F and repeat this for the entire fan blade and the last triangle too ok and now we have to check where these vertices are in comparison to our outer circle so we go into object mode and we select outer circle and then we go with top back to edit mode so top is object and edit mode toggle and we see that we have a very sharp angle here this would be the start of a crack so we have to change our fan blade a little back with top into object mode select our fan blade and into edit mode and now we only select our upper two vertices so shift left click left click and then we move them downward half a millimeter in negative y direction so we type in g y minus 0.5 enter g y minus 0.5 and now we have moved them down ok we need five fan blades all together so now I will rotate multiply it so we select the blade origin to 0.00 and its origin is this orange dot here I am in object mode and now I go to object, set origin origin to 3D cursor because my 3D cursor at this point is still in position 0.00 it is this red and white ring that you see here and you can check its position by looking onto view and see its location is 0.00 back to item ok so far so good and now I need to apply rotation and scale to be sure that the modifier will work correctly and do not do some strange things ok so I will click control A and apply rotation and I will apply scale ok and now I will add an empty add empty this will be the empty around which I will rotate and I still have selected this empty I will rotate it so that I will have five fan blades evenly spread around the 360 degree circle so I will rotate it 72 degrees and I do this with my mouse in the upper left screen here and I type R 72 enter and you see that the empty has rotated ok now I apply the modifier and select my fan blade I go to modifiers I add a modifier array I do not want relative offset I uncheck this I want an object offset I check this and click the little arrow next to it and I select as an object my empty and at the moment I have count 2 so I only have 2 of these fan blades I want 5 so I increase the count 5 and to be able to edit these later I must apply this modifier so I go to wait I go here to apply now in edit mode I see that I can I have all of these fan blades as vertices here in the blender world back to object mode now I must join my rings and my blades so I shift left click my rings when I have already shift left clicked or already selected my blades and I go to object join here and now they are one object ok now to edit mode now I must make sure that they are all part of one that they are all one piece so I must still create some faces and these are for every blade these are the points that I want to put a face into or in between so I have selected them and I press F and here again it's always the lower 4 ones of the circle and the lower 2 ones of the blade F and F make sure that you do not select any of the inner vertices you can also control left click and shift left click what you need and then click F and then in the end you will have joined them all together and also do this with the outside and you can move the screen by shift and middle mouse button and then drag and again control and shift left click F control and shift left click F this we do 5 times for the outside F and here we already have it so now we have one object one flat object but that's the problem it's flat we want to have something that we can print in 3D so now we must extrude it so we have to select everything press A twice to select nothing quickly one after another another AA and once A to select everything ok and now I will extrude my mouse cursor is again in the upper left because I will also rotate so to extrude 2 millimeters I type E to enter now something has happened and I will rotate in negative direction so I will rotate R minus 6 enter so I first extrude it E to enter and then I rotate it R minus 6 enter so minus 6 degrees and now I will continue E to enter R minus 5 enter E to enter R minus 4 enter E to enter R minus 3 enter E to enter R minus 2 enter E to enter R minus 1 enter ok this looks already complicated but it looks ok and if we now go into object mode top we can see this is what we wanted this is our fan that we have now here and now we can save it again to make sure save as one save and we can export it again as STL export as STL and we again make sure that selection only is clicked although in this case we would only have an empty as another object it wouldn't make a difference and again we export as STL and that's it we have our fan and with these examples and the table of tools and modifiers can show those again these are the tools and modifiers you should be able to create a lot of things for hobby and maker purposes what you can also do with blender is import 2d forms that you can create in inkscape for example or you can work with text and wrap the text around objects which is quite difficult to do with construction programs I believe ok thank you and I hope there is still time for questions firstly thank you very much for this informative well filled with the semi workshop we already got a few questions from the audience for you first can the ends of the blades overlap with the outer ring you mean enduring construction I will open it again the ends of the blades so I can so I won't have to join them manually that would not work I mean it would look like it worked if you just do it but then if you try to export it as an STL it would probably be a catastrophe for the slicer program it will not know where one part ends and where the other one begins and will try to slice it into segments maybe there will even be some maybe the file is even damaged or anything so crazy stuff happens if you or can happen if you don't make one complete object out of this yeah alright so we shouldn't the second question how did you change units to the measurements like to how did you do that again it's here to the right it's the scene properties this cone shape and you go to units and I chose unit system none I see alright third is it possible to derive the 2D sketch from the 3D model with measurements preserved to get the 2D orthographic projections with measurements no it would be possible with a normal construction program that's what they are for so at least I don't know a function to do that I use a different program to do that and even then I have to edit mode and look where my coordinates are and then manually transcribe them to create drawings out of them so it would be nearly impossible with this very complicated shape or maybe it would be possible for but actually I can show maybe later a few pictures of these drawings that I did it is possible but you have to do more work than you would have to do with a construction program I see are there documented steps to get to the Blender template the documented steps you mean how I set this up I would say the documentation will be the video of this talk or of this workshop in the beginning I don't have I could make up some slides and upload them maybe but they would be probably an update anyway quite soon because as I said the makers of Blender like to change the interface and the controls when they update it it would probably be a lot of work or quite some work for not that much more gain so I think it's best for if you just watch the video again when it's uploaded and there's just another question coming in just give me a second would it be possible to have an overlap during construction at vertices at the intersection afterwards and delete anything that is now inside the ring let me just go back to edit mode here I'm not sure if I understand the question overlap can you please repeat it would it be possible to have an overlap during construction at vertices at the intersection afterwards and delete anything that is now inside the ring if you have an overlap I can just delete all of these so this is what we started with if we have an overlap here you mean on the outside for example for example I guess at vertices you see here that it tries to pull in the area that it created already so this would be a problem at vertices in between on this I think I know what you mean you can at vertices here if you make a cut now it is with control R it is this what's it called loop cut or something you can add a vertices grab it with G and then put it here but even then you would have the same problem I now delete this one but this vertex here is not connected to the other two so I would have also to delete the line here so I go to edge select I mean I can do that I can now delete the line only the edge and then I'll go back to vertex select and now I can join them these two selected and I can press F again to select them but this is so much more work than just because you would have to do it every time for every blade anyway you wouldn't it wouldn't be an advantage in any way the best do it your way I mean you can do it for some other purposes maybe in the beginning but for this what I did here I believe is the fastest way I did put quite a lot of work into thinking up this thing that I can show and how to make it as fast as possible so another questions coming in are you selecting quarters of the 39 to 40 millimeter circle for the whole thing how I do this it just says are you I'm not sure I mean I selected one quarter so the outer quarter I had to select it in two steps because there's what happened here also I just also select these inner circles and if I now press F it it even did it quite well it put the faces where I wanted them but over the faces that are already there and this would also have happened in that case so yes I select only the parts that I want to create the faces and this is a quarter if I selected the whole half this could maybe work but the safest way to only put faces where you want them is to make smaller steps so quarters is I think a good way to do it all right is it possible to design parametrically so the fan can be adapted to other sizes later I experimented with that in object mode you can make one the position of one object dependent on another but that's been quite a while I don't think I was successful with that so at least it's not that easy I believe but I I'm not sure I don't think so are there more advanced modifiers for this barreling step maybe a screw generator add-on there is a screw modifier here but it's not I don't find it that useful that often so is the question if you can create a screw probably I believe there are quite a lot of blender add-ons and there is one for gear wheels as far as I know there may be one for screws or you can try to experiment with a screw modifier that's already in there but I believe even then if you screw something maybe I can just try it at modifier screw Z axis angle 360 that's probably too much but we are still in one so you can do something with this and maybe you can put it up iterations so there is a screw modifier but I'm not that familiar with it it's possible that you can do more things with that but then even then you have to make sure that you get that you get an object that you can print and you can already see here that it creates many faces in between these screwed the screw modifier part because it will also try to continue all these in-between faces here so you must make sure that your object that you screw doesn't have any in-between ones so these lines would have to be deleted edges so you get only the end points so you must be sure that you have a whole closed object so you can print it complicated to get one done or it will make you will have much work with it I see alright seemingly no more questions are arriving anymore I can show you something more because where is it I wanted to show you what I already did with my how I applied my blender blender ring and 3D printing so you can see here a shower head holder for example it works quite well and I printed it out of translucent plastic or without any pigment in it and it was surprisingly stable it still works or here we were on a conference on a the first congress actually and we needed this for a cocktail bot for a cocktail machine two different tube diameters and I wanted to print this but we didn't have our 3D printer with us and I had to ask someone who had one and he said yeah he would print it and he never did so I was so frustrated and I vowed on this day that I will bring my printer to the conference from now on or here this was a bathroom lock handle enlargement because the especially at parties a friend of mine had to fear that people would lock it inside the bathroom because the lock handle was so small and it was so hard going and then I printed this part with a tapered inside so at some point it would really fit really well on this handle and now it's easy to open it and you would not be able to find as something like this in Thingiverse I believe you really have to measure your lock and design it so it will fit same thing with the shower head holder or here other applications of course the printer here you see it this is you may have you may remember me or may have seen me at one of the conferences or congresses I mean and the one with the really old and glowing 3D printer and these are parts for the printer so especially in the beginning the printer is its own project like the hinges with integrated M3 nuts here so you can put in the nut and then you clip in the blue part and it's part of the hinge you can just screw in and fasten whatever you need on the other side of course you have here the problem you have to fit in the nut in a way that it when it gets turned its forces will be able to the material must take up this force this torsion force of the nut and you have to orient your part so this would be the right orientation if you print upward but then you have weak points in the hinge itself otherwise you cannot really make it right this here is for the printer the filament spool fast clip because you can just clip it open and exchange the filament spool or this blocky part here is a frame bracket at that point you can see I have this tier shaped hole I didn't know or think about enough about the trick of the bridging during printing so I still use this tier shape plastic doesn't flow down these things still hold the printer together what else in our hacker space we let children solder things at certain events so and they have these small soldering kits and the problem is once they are soldered and they cut off the wires and the wires on the back end are pointy the solder metal is not very healthy and usually we would put tape over that and at some point I designed these covers that you can clip on on the backside and they had to be very thin because I didn't want to waste too much plastic and it really took a long time designing and we can print them standing up which is also quite a hassle you have to print really slowly and you have to print many of them at one go because the first one has to have enough time to cool down until the last one is printed so because if the hot printer if it goes too fast back to the original part it will not stand the temperature so you have to print more of them at one go but it worked and we can almost mass produce them but it can be really really troubling you have to stay with this print because they still can break off quite easily and I had once a catastrophe where I had a really big lump of hard plastic around my printer head and I only found out after it had cooled down completely and I had to warm it up again and rip it off and I ripped off one of the wires and it was terrible yeah that's how you learn what else we also have more complicated soldering kits like this solar lamp that we made and for this I designed a highly integrated hold part yeah this is the solar collector and you have the LED and the end is in a jar and the problem was that the plastic melted and got too soft when the sun was shining on it too much so you couldn't keep it in the car or anything but it worked very well apart from that but then what else here a project of our hackerspace that was going to be a present for another one and this is more technical so it's a holder for very well for complicated electrical parts and also for functional parts that had glued in sensors and so on so this but this also worked it was quite a lot of work but it worked on first go with some experience that can work I have to hurry up a little bit here for example if you were on the at the camp this was a cover that I designed for the card 10 batch it's of course not waterproof but it's better than nothing and here there's a beer bottle holder I got the idea when I was standing in line and I was holding a beer and I wanted to have something to eat and I had to pay for it and then I needed a third hand it worked out quite well but I had problem opening it and it broke at some point but well it was an idea then and I tried it but I don't use it anymore here you here are other things you can here see a work with text so you can have name tags on your bottles this is very common in hackerspaces and you can wrap around text with blender quite easily and there's also a description on our hackerspace page how to design this in blender it was uploaded I had this talk for our hackerspace some time ago and many more yeah come to an end I would like to ask you to invite you to join the Franconian at IRC because there are further questions maybe and the audience would like to have direct communication with you so if you can spare a few minutes sure okay we would welcome you there so for now thank you very much you all everybody have a fabulous IRC have a fabulous evening stay healthy and we see you in another talk