Archive for the ‘Tips and Tricks’ Category

3D Modeling – A Need to Learn Skill
3D printers were originally meant to be used as rapid prototyping solution that would allow product designers to relatively quickly get a physical model from the virtual 3D model of something they are designing. These are people with the right set of skills needed to create a product including 3D modeling that use the 3D printer as a helpful tool.

With the boom of interest in 3D Printers in the recent years and these devices getting widely available and at attractive prices for home users one of the most overlooked things is that you will need some skills to properly use these devices. 3D printer manufacturers conveniently forget to mention that it will be good to have at least some basic 3D modeling skills in order for you to be able to create things that you can them print on the 3D printer they sell you.

Surely there are already a lot of 3D models available for you to 3D print and use, but that is not the whole idea of the 3D printer and is most certainly not the best way to take advantage of one. The best thing about having a 3D printer at home is that you can quickly design new things that you may need at home and then start using them, it could be something basic, it could be something more complex… it does not matter. You design it, you print it and there it is doing something useful already and it all happens in a couple of minutes or hours, depending on what you do.

In order to do that however you will need to know how to make virtual 3D models of the things that you need to use the 3D printer for building. That is a new skillset that you need to acquire and the nice thing is that the basics are actually not that complex and you can quickly get into it. Of course you will not be making complex and very realistic 3D characters for use in movies in a couple of days, I talking about much more basic things as a beginning. Then if interested you can continue building on top of that and go to the more complex stuff, it is up to you, but you need to start from somewhere. All that is needed only if you don’t already have the required skillset for 3D modeling, if you do, then you can probably just skip this post.

Why Use SketchUp for 3D Printing
SketchUp is a great tool to get started with basic 3D modeling for use with your 3D printer. I have mentioned it already in one of the earlier posts of the 3D printing series, but now I’ll be going into a bit more details about the software and how to get it ready for use specifically for 3D printing.

Why SketchUp:
There’s a reason SketchUp is synonymous with friendly and forgiving 3D modeling software: we don’t sacrifice usability for the sake of functionality. Start by drawing lines and shapes. Push and pull surfaces to turn them into 3D forms. Stretch, copy, rotate and paint to make anything you like.

Professional tools that can be used for 3D modeling such as AutoCAD or 3D Studio are usually way too complex and confusing for people that are new and are just starting with 3D modeling. Of course these are much more powerful and allow you to do more complex things, if you know how, but getting started with them is much harder than with a simpler and more user friendly tool like SketchUp for example.

There are two different version of SketchUp – Make and Pro. The first one is completely free and can be used by anyone for personal projects and educational purposes, though you should know that SketchUp Make is not licensed for commercial work. For professional work you would need to go for the commercial version SketchUp Pro. The good news is that the free SketchUp Make is more than enough for your needs to get started into modeling 3D objects that you will later on 3D print.

Apart from being licensed for commercial use the Pro version has some extra more advanced features, once you install the Free Make version you will also get a 30 day trial of the Pro functionality, so you will be able to explore these as well. More details about the extra features available in the Pro version are outlined in the table above, again the basic functionality is available in the free Make version, so no need to buy anything.

Configuring and Setting Up SketchUp for 3D Printing
When you start SketchUp you get a choice of multiple startup templates available to use that may help you based on what you are planning to be modeling inside the software. There are two Templates available for 3D printing as well that might be somewhat handy initially for some users.

The templates are called 3D Printing – Inches and 3D Printing – Millimeters and apart from setting your working units inside the software for the object sizes (Inches or Millimeters) they also give you another helpful tool – a box that represents the available build size of a MakerBot Replicator 2X 3D printer.

You can use the box as a guiding point for the size of the 3D object that you are designing if you have a 3D printer with a similar maximum build size or if you got the Replicator 2X. If you don’t need that extra guide (it is essentially a 3D model) you can just click on it to select it and hit the Del key to remove it from the workspace. Alternatively you can easily design a similar 3D model that reflects the actual build size of the 3D Printer you have available, so that it will be more useful as a reference.

Initially when you start SketchUp you get it configured with a simpler line of tools at the top of the software, however I don’t find that one very useful, so I prefer to switch to a different and more functional one. To do that you can either use Right Click on the toolbar or go to the View menu and then select Toolbars

The standard one is called Getting Started and the one I’m using is called Large Tool Set, you just need to right click on the line with the tools and select the Large Tool Set (it will show on the left side) and then do the same, but unselect the Getting Started one to remove it from the top. There are more Toolbars for you to choose from and you can experiment by turning on and off some of them until you customize the workplace you find that is most convenient for you. What I prefer is not to over complicate things and the Large Tool Set is enough for me most of the time.

The Large Tool Set gives you an easy access to the selection tools, the basic shape drawing tools, the object manipulation ones, the measurement and tools for changing the viewing position. These tools are also accessible via the menu of the software as well as via a special shortcut keys that you can learn while using the software to make switching even faster without having to use the mouse to click on different tools.

Extension Warehouse and 3D Warehouse
The Extension Warehouse is a place you need to get familiar with as you need to start with the installation of a very important Plugin from there that is required for you in order to be able to import and export STL files (the file format used by most 3D printers). By default SketchUp does not come with that Plugin and there is no support for STL, so one of the first things you need to do is to add that support.

You need to call up the Extension Warehouse from the Window menu of SketchUp, it will open in a new window and you need to search for the SketchUp STL Plugin and install it. It is a free plugin, and even though the Extension Warehouse does also offer some plugins you need to pay for, there as a lot that are free to use like the SketchUp STL.

Once the SketchUp STL extension is installed you will get the ability to import STL files from the File / Import menu as well as to save STL files via the File / Export STL… option that will become available. Prior to installing this plugin STL files are not supported by SketchUp!

The 3D Warehouse works in a very similar way to the Extension Warehouse, however instead of giving you access to additional plugins you can install, you get access to many free to use 3D models. This might not be that useful when designing a 3D model for 3D printing yourself, but you might still want to check if there isn’t a 3D model of the thing you are trying to do that can save you some time. Also if you are designing some scene that included multiple items in it can be handy just to import some readily made 3D models in it.

Note: The 3D models available in the 3D Warehouse are not designed primarily for 3D printing, so some of them might not print without problems or at all due to various reasons, so do have that in mind if using them!

Now is the Time to Finally Make Something
It is time to start playing around and experimenting with the basic drawing shapes such as the Line, the Freehand tool, the Rectangle, the Circle, the Polygon, the Arcs and the Pie. After you draw some 2D shapes you can try the Push/Pull tool to turn them in 3D objects, you can further move them around, rotate them, scale and offset and so on. Do try adding some 2D text first, and then try using the option to Extrude it and have it in 3D. You can also import 2D vector shapes made in another software and have them become a part of your own 3D objects. As I’ve said these are the basic building block of 3D modeling, but after a while you might be surprised to see how powerful they can be and what kind of things you might be able to make using only the simple forms and shapes.

I’m not going to go into too much details about using the SketchUp software now that you are ready to play with it, instead I’ll leave it to you do play around and discover things.

Check the official video tutorials for learning SketchUp…

YouTube is also a great source for finding many other video tutorials on how to design various things in 3D using the software, so go learn something else new…

Once you have designed a 3D model that you want to try 3D printing what you need to do is to just select the geometry of the object you want to export (no need to select anything if you are exporting everything) and go to File / Export STL.

Here you can select if you want only the selected geometry to be exported or the whole scene from SketchUp. You can change the type of units used for the exported STL, essentially scaling up or down the model, though normally you don’t want to play with this settings if you used the right type of units designing the 3D model. The third option is to have the exported STL file in Binary or Text format, choosing either should work, unless of course your 3d printing software supports only one of the two types of STL files.

Note: Make sure you have selected something if you are not exporting the whole scene, as if there is nothing selected the resulting STL file will be zero in size (there will be nothing inside it).

Before I go on with explanation of Raft and Support and why and how you can or need to use them I’ll have to go for a sample 3D model meant for 3D printing that has the right design for my specific needs. As going only with some short text explanation might be hard if you are novice to 3D printing, so instead I’m going to show you how and when you can take advantage of these feature as well as why they can be helpful if you are having trouble 3D printing some things.

The good example I’ll be using is a new 3D model of a 3D printable espresso coffee cup you see on the image above. A Word of Caution: It is not a wise idea to 3D print models such as cups for hot drinks from thermoplastic materials and then use them to hold something with a high temperature such as tea, coffee, or even water!

What is Raft and How to Use it
The use or not of Raft is one of the basic 3D printing options that you have available as I already explained in the previous Blog post from the 3D printing series of articles I’m working on.

Raft is a special additional base that is being 3D printed below your actual 3D model. It is being generated automatically for you if you activate the feature. You may need to use it if your 3D model has a very small base and is having issues sticking to the build plate for example. It could also help with larger 3D prints where one of the edges of a larger base of the model starts peeling off the build plate, you would of course need to restart the print.

I bet that as a novice user you don’t see any potential problem in 3D printing this espresso coffee cup on your new 3D printer, but as you gain some actual experience printing things you will start to notice these just by taking a quick look at the 3D model. It is not necessary that you might have issues printing the 3D cup, but there is the potential for issues on some 3D printers. I’m saying on some 3D printers and talking mostly about FDM/FFM-based devices, because these ate the most commonly used devices by home users. On a high-end business class 3D printer that may use other materials such as ceramics or metal you are much less likely to have a problem because of the different way of doing things there.

So back to the potential problem that the use of Raft may resolve with this 3D printable coffee cup used as an example. The base of the cup has very little contact surface with the build plate of the printer. If the first layer of the print does not stick very well to the printing base you might experience unsuccessful print soon after the model starts to get printed. This can happen as the print head moving around and building layer by layer can apply some pressure on some of the sides of the model and cause it to detach from the build plate if it is not sticking well. This may never happen of course and the 3D model may still finish printing without an issue even with the small contact area it has with the build plate.

By activating the Raft option in the 3D printing settings what you will be getting is the 3D model you want printed to rise by a few millimeters and some automatically generated structure will be added below it. That structure is the so called Raft that will expand the contact surface with the build plate (base) between the 3D printer and the 3D model you are printing. Don’t worry, the extra material added at the bottom of the cup is not that much and it is easier to remove from the base and from the 3D printed cup or whatever model you are using.

The side effect when using an additional Raft is that the base of the cup may not be as even and flat as it would be if it is directly attached to the build plate without the additional Raft. This you can still easily fix with some sanding of the base of the 3D model, but it does require additional attention. Of course this may vary from printer to printer and from model to model that you print, so it is not an always needed additional step to perform.

Another issue that using a Raft may help you with is when you are printing a larger 3D object and one of the edges starts detaching from the build plate as the model is being printed. You can still get the model to finish printing if it has a larger contact surface to the base of the 3D printer, but it will be slightly deformed at the problematic edge. Activating a Raft is such a case can be helpful, though may not always resolve the issue as it may be caused by a serious problem with the leveling of the build plate. That however is another different issue that I’ll be discussing about at a later time and not in this post.

What is Support and How to Use it
So let us get to the other thing that I need to explain with example, the use of Support and why you need it when talking about consumer grade 3D printers. But first let us remember the explanation from the previous Blog post:

Support is additional structure that also gets automatically generated and added to your 3d model in areas that need some additional material to assist in properly printing them. There is no way a 3D printer can print a part of a 3D model that just hangs in the air and has nothing to hold it to the base of the printing surface, this is where the additional support material comes to help and resolve the issue by allowing you to print the model. After the print is ready you can just remove the extra support material that was used.

So time for another look at the 3D model of the cup in the 3D printing software, in this case the software is MakerBot Desktop used by the 3D printers from MakerBot like the Replicator 2 that I’m using. Reading the description above and looking at the model you should quickly realize that the cup handle is mostly there in thin air with no connection to the build plate. This means that when the 3D printer reaches the lowest part of the handle it will just start to extrude material in thin air and the 3D print will essentially fail with an incomplete cup. That is if you don’t add Support material to assist in connecting the parts that hang in thin air to the base of the 3D printing surface or other parts of the 3D model.

If you activate the use of Support then the slicer (printer software) should calculate automatically where it needs to add them and will apply them where needed – you will see them added in the preview window before starting to print. The software for 3D printers is usually pretty smart and does a good job at adding Support material when needed, but sometimes it may fail to do its job properly and unfortunately not all slicers also come with the option for the user to add manually additional support structures or to remove existing ones.

As you can see on the above image the slicer for the Replicator 2 3D printer did a pretty good job on adding Support for the handle, only as much as really required. It also has added some support material to other areas of the 3D coffee cup – some at the base and some even on the steemit logo on the side. Some of these areas could do just fine even without support material, but the handle of the cup cannot simply be properly printed on an FDM/FFF 3D printer without the use of Support material. Unfortunately the MakerBot Desktop software is one of these slicers that does not yet have an option to allow the manual addition or removal of support structures, so you are stuck with what the automated algorithm does.

When is Support material usually a must have for proper printing? The answer of that question is a bit harder as you will learn yourself as you gain experience printing different things. As already mentioned in the case of the cup handle it is a must have, but some of the other parts where Support structures were added may just do fine even without the extra material. They could either print just fine or with some tiny defects that should not affect much the general appearance and usability, there are some simple rules that can be helpful however.

The use of Support structures is a must when you have elements of an object that are horizontal and/or point at a downward angle like in the case of the cup handle without them having contact with the base (they need to be printed in thin air and there is no way that will happen). If something is horizontal and in thin air, but is just a few millimeters short like the steemit logo on the cup you might up getting lucky even without support structures and getting either a good print or slightly not so good at the bottom.

If you have a part of the 3D model that is at steeper angle, not pointing down, but up instead like the upper half of the cup handle next to the main body of the cup you should be able to do fine without support material in most cases. If the angle is upward, but just a few degrees from the horizontal level you might be lucky without Support structures if it is just a few millimeters long, but if it is longer it will still require Support material.

Why You Need Both Raft and Support for the Example Cup
If you want to have a successful 3D print of the coffee cup that I have used as an example for this Blog post about 3D printing you will have to use both Raft and Support. I hope that by this moment you have understood what exactly each of these two functions does and when and why you need to use it. If you still have some doubts, don’t worry, you will quickly get the hang of it when you print some 3D models successfully with and without Raft and Support structures and when you get some failed prints and you analyze what went wrong.

Now for the coffee cup and why you need to use both for a successful print. Normally the cup might have been just fine for 3D printing without Raft if it did not require the use of Support material for the handle. When you activate the generation of Support material the base of the cup gets some extra contact surface to the build plate thanks to the extra support structures added. However the support for the handle is very thin and as a result there might be issues with it sticking to the build plate and remaining stuck to it as the printer goes up layer by layer building up the cup. The potential issues that can be caused by the small contact surface of the support material can be avoided with the addition of a Raft. So in the end you will need both Raft and Support activated to get a good and successful print of the 3D model of the coffee cup, don’t worry, you should be able to easily remove the extra material added by the two additional options.

So you have just received your first 3D printer and are wondering what you should do now as soon as you open it up and install it. Baby steps, baby steps. Don’t be in a hurry, you will get there eventually, you will need to start from somewhere like for example actually 3D printing something yourself on your new and shiny 3D Printer, but what?

Start by 3D Printing Some Stuff
Some people start by 3D printing some of the sample 3D models that they got along with their 3D printer, you can do the same thing or maybe try printing something else. Either way the very first 3D printed object you have is something that you would want to keep and later on show to friends what was the first thing you made with your new gadget.

Alternatively if you want to start with something more complex and risk having your first 3D print turning either no so successful or unsuccessful you might try to print a Star Wars Yoda bust for example. A popular choice for many people among the first things that they make with their 3D printers, even though it is a larger and more complex object that may cause some printing, even I have printed it soon after I got my first 3D printer.

You want to try printing something else or to just browse around and find other interesting things to try 3D printing now that your first 3D print is ready. No problem, as there are many places where users share and provide the 3D models ready for 3D printing for everyone to download and try. Furthermore many of the generic 3D models designed by people can be converted and 3D printed without too much trouble, so this seriously extends the choices. Though we aware that is a specific 3D model has not been made for 3D printing or at least optimized for you might be in for some headaches trying to make a physical object out the of the virtual 3D one… especially if you are a new user.

Thingiverse is a very good starting point to find a lot of user made 3D models designed mostly for 3D printing and there are many more other such websites out there. Just use the search functionality on the website and you will be surprised by the number of results you get on various keywords, there are a lot of things available there and they are free (check the usage licenses under each model). Of course there are also websites where people sell their own designs ready for 3D printing and there are also services that offer visitors to choose a 3D model and have it 3D printed and delivered to them. I’ll leave these for a later time however as now there are more important things to focus in your journey to get to know your new 3D printer.

Try to Make Some Simple 3D Models Yourself
Not everybody knows how to model things in 3D space, in fact very little people with that knowledge go and get themselves a 3D printer. Sure it is fun for a while when you have an enormous resources with 3D models ready for 3D printing that are waiting for you to download and try. At some point however you start thinking that you can make small and simple things on your 3D printer if only you know how to model them in 3D.

The thing that nobody tells you about 3D printers is that it will be good if you know how to do 3D modeling, companies just want to sell you their hardware and leave the rest to you. They say it is easy to use and problem free, so go ahead buy it and enjoy it… and then you start learning the hard way that things are not exactly as they were marketed. So actually buying a 3D printer is the first step you do in a long learning process ahead of you and learning to make 3D models yourself is an essential part of that process.

The good thing is that it is actually not that hard to learn the basics if you start with a simpler and more user friendly tool such as SketchUp (available in a free version as well), so no need to buy any software either. You might’ve heard about the software as Google SketchUp as it was owned by Google a while ago, but not anymore, now it is Trimble SketchUp.

What SketchUp does is provide you with a basic 3D workspace and a few more basic tools that you can use to start designing not so complex 3D models yourself. The software comes with access to the so called 3D Warehouse, essentially big library of free 3D models designed for SketchUp that you can download and use and also export for 3D printing. There are also numerous plugins available for the software that can extend its basic functionality, in fact you will need to install one just to be able to import and export STL files (the most commonly used file format by 3D printers for 3D printable models).

It is learn and experiment with this tool, reading some basic tutorials about it can also be helpful if you are completely new to this. I’ll be talking about SketchUp more in a future post as there is more needed to be done for properly using the software for 3D printing. I’m just mentioning it for now, so that you can give it a try if interested and maybe even play a bit with it. It does have a free version that is fully functional, though it may lack some more advanced features, but you probably won’t need these initially anyway.

Learning the Basic 3D Printing Parameters
There are a couple of important printing parameters that you have control of that can greatly affect how things are being printed on your 3D printer. I’ll try to cover the most basic ones now, because not using them properly can lead to you getting trouble printing properly some or even all objects that you try. As you continue your learning you will also find out that there are a lot more advanced printing parameters that you can also play around with or tweak to get better results or to make a successful 3D print of something normally harder to print.

The above screenshot is from the standard 3D printing software (slicer) for the Makerbot Replicator 2 3D printer, other devices may have different visualization of the basic 3D printing parameters, but they should essentially be the same. The of course could be some difference in the exact names used, though you should still be able to guess as to what they are referring from the list below.

Layer Height or Quality is the most important setting as it chooses what level of printing quality you are going to get. With it you change how thin or thick each of the printed layers that build up the physical 3D model will be. A lower the number means thinner layer and better quality, but also more time needed to print, a higher number means lower quality as fewer layers will be needed, but also faster printing time. Common settings are 0.3 mm, 0.2 mm or 0.1 mm for the layer height, though these values may vary from one 3D printer to another.

Infill is a percentage value that represents how solid a 3D printed model should be. Going for 100% means that the inside of the 3D printed object will be completely solid, going for 20% for example will result in having a semi-hollow structure inside that will be reinforced with hexagonal or square patterns. Most 3D prints are just fine with between 10% and 20% percent infill as it is enough to provide good strength while also reducing the needed material and the extra print time that a fully solid insides will require.

Number of Shells represents the number of outer shells or walls that you are going to have on a 3D printed object before the inside part starts. The outer shells are fully solid while the inside part can be solid or semi-hollow based on the Infill percentage you have set. Normally the default value of 2 or 3 should be enough and you won’t have to change it.

Extruder Temperature is the operating temperature at which the printing head needs to heat up while the 3D printer is extruding the printing material (filament). Depending on the type of filament you are using you may have to change this temperature, for the more common PLA materials 230 degrees Celsius is usually fine. If the temperature of the extruder is too low it may not be able to melt well the thermoplastic material that is used to build your physical representation of the 3D model and it can jam the print head. If the temperature is too high the printed thermoplastic material may deform and the resulting print may turn out to be unusable or with very low quality.

Raft is a special additional base that is being 3D printed below your actual 3D model. It is being generated automatically for you if you activate the feature. You may need to use it if your 3D model has a very small base and is having issues sticking to the build plate for example. It could also help with larger 3D prints where one of the edges of a larger base of the model starts peeling off the build plate, you would of course need to restart the print.

Support is additional structure that also gets automatically generated and added to your 3d model in areas that need some additional material to assist in properly printing them. There is no way a 3D printer can print a part of a 3D model that just hangs in the air and has nothing to hold it to the base of the printing surface, this is where the additional support material comes to help and resolve the issue by allowing you to print the model. After the print is ready you can just remove the extra support material that was used.

You may have some trouble understanding how some of these settings work at the moment, but as soon as you start playing with them you will be able to see how they affect the printing process. I’ll also be further covering them in another post with examples and some tips, so the above was just to give you an idea what each of these printing parameters does.

Are You Ready to Learn Even More
The fun things are just about yet to be discovered and you need to be ready to learn a lot of new things about 3D printing and 3D printers as you start trying to print different models or build your own. You will need to learn about different filaments, how to get better quality prints, how to avoid failed prints, and so on and so on…