In order to start to fabricate something digital, you will need to create the data, or drawing for the process.
This counts for 3D printing, CNC cutting and Laser cutting.
And, will it be 2D(laser,CNC) or a 3D (3D printing, CNC) file you will need to create ?
For this post let’s focus on 3D file generating.
As there are many packages available, from free to the price of a car, I will cover 3D packages from free to £800/ USD1000.
If you are a starter, I would advice to start off with some free versions.
I want to point out that there are great free/open source packages available, and there is no need to fork out loads of money.
So where to start ?
First ask yourself what is it what you want to model ?
Is it a detailed furry animal, piece of jewellery or a technical part which needs to be accurate? this is a question that you will need to ask yourself, as not every design can be modeled with every 3D package.
Roughly there are two kinds of 3D modelers: sculptural and technical.
sculpture like packages.
If you want to 3D model animals, human figures and organic jewellery a sculptural package is your best bet.
This because you get a easier to create organic end result, and don’t need to worry to much about dimensions. This doesn’t mean you can’t be dimension accurate with these packages.You are just a bit freer during the 3D modeling.
The sculptural modelers can also be split into two different types.
Mesh or box modelers, and the clay like sculptural modelers.
In the mesh modelers you start out with a geometric shape, a cube for example, that you sculpt into an object by extruding and insetting faces.
The final model can then be made smooth with a function called sub division.
See this video as an example how a rabbit head is created from a sphere:
3D studio MAX
Then there is the more clay like modeler, where you start off with a blob of digital clay.
you will have a set of tools, to carve in or to extrude some of the digital clay.
Windows 3D paint (free in Windows 10)
Some package offer mesh and clay sculpting, such as Blender and 3D COAT.
The technical packages are best for models that need to have an accurate dimension, with easy dimensional control.
Think of a enclosure for a raspberry pi, a mobile phone case or a multi part design such as a hair dryer.
Just to be clear, This doesn’t mean you can’t 3D model somthing accurate in a sculptural package like Blender for example.
In the technical package you will find more tools to construct technical and dimension accurate features.
Also the workflow of technical packages is a bit different.
Instead of sculpting a primitive, or a blob of digital clay into a model, 3D models are mostly created with a 2D sketch that then is extruded, lofted or swept.
Create a model from several primitives is also possible.
Unfortunately Autodesk stopped the support of 123D, which was a great starter package I have mentioned in a previous post.
That leaves the very basic web only based tinkercad, or the less ideal for 3D printing sketchup.
The technical packages can also be split into two, direct modeling and parametric modeling packages.
Direct modeling packages are very flexible and a bit easier to understand then parametric packages.
This is as you don’t need to plan how you are going to draw.
You can simple just start on a blank canvas.
Draw a curve, extrude it, stick something on top, join it together.
Work on several models the same time is also no problem.
Direct modeling packages, such as Rhinoceros are also great for data import ,extraction and export.In Rhino it is easy to extract a 2D curve from a 3D model.
Difference between direct and parametric.
But if you want to make a small or big change, you most likely need to start again.
Let’s say you made a enclosure for some electronics with some screw holes.
And all the holes are to big, and on the wrong location.
This means some manually work.
In a parametric modeler you can simply go back to the 2D sketch that is used for the holes and change the values.
Let’s say you want the rounded corners a bit stronger on the coaster.
In a direct modeler this means re drawing the outer ring.
In a parametric package it mean just simply changing a value.
So what I normally do when using a direct modeler, is make a copy of my design if I’m going to do a big process, so if I want to go back, I can simply use the old copy.
At the end you have loads of different versions, which is also a nice way to analyse your design path.
You might think you will need to have the parametric features, for small and my own designs I just use a direct modeler.
This as I normally know what I want, I’m reasonably quick with remodeling, and I like to keep all my different designs I started from scratch again.
with a parametric modeler, I would be kept with one model, as I can make changes on the fly.
If you work for clients jobs, it might be worth it to use a parametric model, as you can execute changes quickly.
FREE, Direct modeling.
Tinkercad (web based)
Easytoy 3D Old 3toy design software.
Moment of inspiration
The most popular parametric model is probably solid works.
As it cost $4000, it is defently not the most expensive.Siemens NX is is around $20000.
Does a parametric model need to be so expensive ?
These are all professional packages.
Solid works is used to design precsision products such as power tools, ans Siemens NX is used to design F1 race cars, sub marines and power plants.
There are some great free and lower price alternatives.
Fusion 360, free for makers, else $300 a year.
Fusion 360 has loads of dimensional control, and is parametric as well.
This means you can program certain dimensions, that later on can be easily changed.
One thing to keep in mind is that you will need to have an internet connection to access your files.
Local saving/working is possible, but an internet connection will be needed after being 2 weeks offline.
Rhino VS Fusion 360.
Rhino is a great package, it is the package that I know best.
I learned it when I was an Architectural Model Maker.
Rhino is really powerful, and great if you work with architectural models, or other big chunks of 3D data.
In compare to fusion 360 it is showing it ages when it comes to creating fillets and creating 3D printable objects from scratch.
On the other hand, you have more direct control on your data in Rhino, as Fusion sometime assumes what you want to do and makes decisions for you.
Rhino has great curve creation tools as well, something I miss in fusion 360.
But for a starter I would advice using Fusion 360.
Main reason is the low price-free, and the big community around it.