May 29th, 2013
10 Tips For Modeling For 3D Printing
3D modeling brings you out of space. It loosens your hands and releases your fantasy. You can sculpt, combine, model, shape, form any most ridiculous object that contravenes physics and is far beyond the reality. Since CGTrader.com is holding 3D Printing Competition, there are a few things each 3D designer must definitely know about.
When you design a print-ready model, a process of modeling changes a bit. While modeling 3D printable objects, you must always be aware of the reality. At least, a little. In order to answer all your questions and save your time, we offer to look through these guidelines to make sure that your modeling is going to the right and bright side. Special thanks to our 3D printing competition's sponsor 3DPrintUK for simple, but amazing visuals!
1. Forget Surfaces
Keep in mind that the walls of your 3D model must be thick enough. If you want a model to be 3D printed, a wall must be not less than 0,5 mm, 1mm would be your absolute guarantee. So, as 3DPrintUK reccomends, draw in solid bodies, because they are easier than surfaces. If you are not fully convinced, watch this video:
2. Shut Your Model's Face
Open faces do matter. To make it simple, an open face is where a model is missing a face from the surface of the part. In other words, an object must be so called waterproof. If there are any open faces left after your modeling, close them. If not, it will not be possible to 3D print it.
3. Separate Edges
Be aware that your 3D model must not contain any shared edges. Better replace it with a 0,1mm gap between two bodies or just overlap if parts have to be joined together. Otherwise, it results in a crash of 3D printed object. Damn.
4. Correct Normals
All surfaces of a designing model must have their normals pointing into the right direction. Happens that your 3D model contains inverted normals, so most of 3D printers cannot determine the inside or outside of your mesh.
5. Hollow Your Models
3DPrintUK advices to hollow out large volume objects. Hollowing saves you money, because filling model's inside with expensive material is pointless. Take a look at huge price differences! Only by hollowing a model, this designer has managed to save 80% of the amount!
6. Scale It Down, If You Can
Another way to reduce 3D printing price is to scale your model down. Think twice if you do not want to make it smaller. If you cut the size in half, you will reduce a printing price by eight times. Worth to consider.
7. Stay Within The Limits
3D printers have a particular volume which you cannot build larger than. If your model is larger than the build volume, either break it down into smaller individual components, or cut join lines through the model. Model reasonably.
8. Always Leave A Gap
While designing moving parts of a 3D model, always keep in mind to leave a gap between them. It must be at least 0,5mm in order not to stick and provide an unobstructed movement.
9. Keep It Stable
In the 3D printing's slang there is a so-called 'thin arm syndrome'. You must not leave thin arms with unsupported weight at the end. Especially after scaling a model down, be sure that the arms are strong enough to hold it. Moreover, shapeways reminds that your 3D model will always stand on its' feet, while a real one may keel over. So, consider the size of a character and the shape of contact area. It must not be significantly smaller. Or keep in mind that you always can add an artificial base for stability of a model. This is an example, how the size of contact area properly matches the dimensions of the object:
10. Model Characters Accurately
While modeling a 3D printable character, you must be careful about the details more than ever. Even the smallest part does matter. Make the arms and legs of your model strong enough. Just imagine Shrek, standing on two tiny legs. Do not forget that any surface details must be supported on at least one side of the another surface. Thinness of it should not be less than 0,4mm. Fingers are vulnareble part of a body. So, they are likely to break the first ones. Try to keep them together.
Put your character on two feet better than on one. If you want it to raise a leg, put it on a stone. Furthermore, avoid precisely small details. If you are not sure if you can print it out, better remove it. Do not experiment a lot in character's shape also, keep body parts going across or along X,Y or Z axes.
Yes, it is a lot to remember. But you can always follow these guideliness in order to design a proper 3D print-ready model. Do not think that these are the rules to restrict your creativity. We need it. That is why originality matters that much in our competition.
Tell us what you think!