Creating three-dimensional models for 3D printing requires the use of software that can generate this type of models. In fact, the creation of models (modeling) can be done using the most appropriate software, to be chosen according to your needs.
However, many of the software that follow offer the same functionality, and probably, the same functionality will have different names.
Professional software is usually the most complete and rarely needs external tools (these are special cases that arise if you work in advanced mode).
The use of some types of tools external to the main program may however, in some cases, be preferable for several reasons.
The main differences:
If the model we intend to produce is a “mechanical” one, i.e. a three-dimensional model with precise dimensions, or based on precise dimensions, and where all dimensions must always be accurate, then our choice must be a direct modeling CAD software or a parametric CAD software.
CAD Direct and solid parametric modeling
With this type of modeling you generally start from two-dimensional shapes such as lines, circles, arcs, etc., you place them and size them according to the object you want to obtain and you assign a thickness to them. It is also possible to draw holes and/or recesses within the model, always starting from two-dimensional geometries and using appropriate commands, “remove the excess material”.
“Freehand” polygonal modeling
In case you want to make an “artistic” model, where size matters, but up to a certain point. Or where not all dimensions need to be precise and accurate. Then our choice can easily fall on a software for modeling “freehand”.
These are examples of polygonal modelling, where, starting from a basic solid (plane, cube, cylinder, sphere, etc.) and adding other polygons (vertices, segments, faces) using different methods (extrusion, insertion, connection, etc.) and transforming it (moving, scaling, rotating), we obtain the final model.
But you could start from a circle, from a series of lines ( polyline ), from an image, from a “map”, using the “modifiers” etc…
“Freehand” sculpting modeling
These are examples of Sculpting modeling. In sculpting you always start from an initial solid, and the method of modeling is then comparable to that used for modeling the clay. There are a number of tools available for adding material, removing material, compressing or extending the material, etc. As you proceed with the use of these tools you get the finished model ( The sculpting type modeling is preferable if you have to make an organic modeling type )
Below, you can read a further definition of 3D modeling, taken from an article published on Wikipedia:
From a typological point of view, the whole 3D modeling is part of two big families, each one concerning a specific kind of models:
- Organic Modeling – is the typical modeling used to make humans or creatures, animals or humanoids. It is used for all “natural” subjects, such as rocks, plants, trees and for the territory in general, in these cases the models are more successful the more they are rich in detail. Also many objects of industrial design, which have soft and rounded shapes, can use an organic modeling.
- Geometric modeling – is the oldest type of modeling. It is used to make technical or mechanical objects, or for anything that has an artificial nature, and that does not fall into the previous category. Generally, the complexity of the models made with this kind of modelling is much lower, if we look at the external aspect of the single shapes, but not if we consider aspects related to the precision and correspondence of the parts.
Of course, the same object can contain both organic and geometric modelling, or it can be formed by a set of parts containing both organic and geometric models.
If you are interested in reading the whole article click HERE
Types of modeling
- Manual: Everything is done by hand. Sometimes with the support of graphic tablets.
- Procedural: The final model is the result of mathematical formulas and/or its “programming”.
- For scanning: From a series of photos, or from a scan with a 3d scanner (Point Cloud) it is possible to obtain a more or less “faithful” copy of the photographed/scanned object. (Also colored with textures already applied).
Common types of geometry in 3D modeling
- Polygons are flat shapes defined by three-dimensional points (vertices) and straight lines that connect them (edges).
- Polygonal modellers generally use 3-sided polygons called triangles or 4-sided polygons called quadrilaterals.
- Polygonal surfaces are applied on a large scale and are the preferred surface type for animated effects in movies, game design and 3D web development.
Curve and NURBS modeling
- The NURBS, acronym for Non-Uniform Rational B-Splines, are made up of curves defined by a mathematical formula.
- The use of NURBS is ideal in the modeling of polished surfaces with complex curves, such as a wine glass or a soccer ball.
- NURBS are more widely used in mechanical or industrial design.
Modelling with subdivision surfaces
- The subdivision surfaces have the characteristics of both polygonal and NURBS surfaces.
- Like NURBS surfaces, subdivision surfaces can produce uniform organic shapes and can be modelled using a relatively small number of control vertices.
- Like polygonal surfaces, subdivision surfaces allow you to extrude specific areas and create surface details when necessary.
So, which software to choose?
If we have to make technical models, we will have to prefer software such as (just some)
OpenSCAD ( procedural )
Fusion 360 ( parametric )
Autodesk Autocad ( direct modeling ) ( Free Trial Available )
Autodesk Inventor ( parametric ) ( Free Trial Available )
Dassault Systemes SolidWorks ( parametric )
Dassault Systemes CATIA ( parametric )
Rhinoceros Rhino3D ( Direct Modeling ) ( Free Trial Available )
If we are to realize artistic models, we will have to prefer software like ( Manual technique, polygonal, only some )
SideFX Houdini apprentice
Google SketchUp ( free )
Autodesk 3DS Max ( Free Trial Available )
Autodesk Maya ( Free Trial Available )
Maxon Cinema4D ( Free Trial Available )
Tinkercad (Browser )
Rhinoceros Rhino3D ( Trial Version Available) + Grasshopper
Manual technique, sculpting, just some
Autodeks Netfabb Basic (at the Trial expiration )
Others – Free
SculptGL ( online web browser )
Photogrammetry – From a Picture to a 3D Print
COLMAP ( with or without NVidia CUDA )
Vi3Dim ( Microsoft Kinect necessario )
Autodesk ReCap ( versione di prova disponibile )