Getting started with 3D printing using Linux

15 January 2017

I have now got a 3D printer. I haven't done much with it yet and it's a steep learning curve but I'm looking forward to getting into 3D printing.

Choosing a 3D printer

The first decision was which 3D printer to buy. There are a lot of different choices starting from little over £100 and going into several thousands of pounds. The one that I opted for was one of the more expensive budget ones costing a few hundred pounds. It is made by Wanahao, the model is the Wanhao i3Plus Duplicator. The i3Plus integrates the control unit with touchscreen into the main printer instead of needing additional unit, this does mean it takes up less space on the desk.

One of the things I wanted was a 3d printer that was based on the open source Prusa design rather than a proprietary design. This means that it is possible to upgrade or change the printer in future, such as by changing the printer extruder to support different materials. It's not something that I necessarily plan to do in future, but I like to keep that option open. It also means that if there is an updated version of the file format then I could potentially use that by upgrading the firmware (software) which may not be available with a proprietary printer. Some 3D printers even go so far as only allowing their own plastic being used such as the XYZ Printing Junior. There may be some benefits to using the printer approved materials, but this could also be restrictive.

Wanhao i3Plus 3D printer

Another benefit of the Wanhao printers is that the printer is supplied partly or fully assembled, whereas some printers are provided as a kit which involves assembling all the individual components. In the case of the Wanhao i3Plus Duplicator then the main parts of assembly were to attach the vertical assembly to the base and connect several wires by plugging them into the relevant connector sockets. This means that the printer was up and running within an hour of opening the box, whereas with some other printers it may take several hours.

Another consideration is that the mains electrical connections are fully enclosed within the printer. On some of the kit printers this is sometimes in the form of a separate power supply block which is connected directly to the mains. Just looking at customer reviews one 3D printers includes the quote "The power supply has to be wired to mains and the live wire is only covered by a small flap..potential for shocks exist...". I haven't verified this myself, but it is an additional thing to consider if you then need to add an additional enclosure for the power supply.

One feature that this printer doesn't have that I considered is a dual-head. I can see that there are instances where that may be useful, but I did not think it essential for my first 3D printer. It also doesn't have a self-levelling base, which some 3D printers do include.

This isn't the only 3D printer which ticks all those boxes, but it is one that did and I'm happy with the 3D printer I bought.

SD Card included with the 3D printer

The most common way to print on the 3D printer is by saving the print files to an SD card and inserting that into the printer. An alternative is to connect a computer directly to the 3D printer, but that could tie the computer up for a long time.

The 3D printer includes an SD card which includes some free software, but that software is Windows only. It also had one sample 3D object to print (although it said that it should have more than that). It does mean that it's possible to get up and running with your first test print without first needing to find / buy an SD card or connect to the printer by USB.

3D Printer Slicing Software

If you have a 3D CAD file that you would like to print then it needs to e converted to a GCode file which is used by the 3D Printer. This is through a process known as slicing where the 3D object is split into slices or layers. The slicing software can also add additional things, such as additional support material and can determine how much material is used for solid objects (which are normally printed with a mesh rather than solid material).

The most popular slicing software is Cura, which is open source software. There is a version provided by the manufacturer that includes the specifics about the printer, but that is for Windows only. I used the standard Linux version and then for the printer type choose Prusa i3 which gives reasonable results.

Unfortunately the Cura GUI will not work on the Raspberry Pi as it requires OpenGL, but that is still work in progress on the Raspberry Pi, but it will work on Linux running on a PC. The Cura back-end is provided for the Raspberry Pi, but that is command line only.

An alternative slicer software is slic3r. This is available for Linux including the Raspberry Pi repository. The version that is compiled for the Raspberry Pi is an older version and I'd recommend trying to use an updated version as it is much easier to use.

Slic3r needed some configuration for the printer and the following are the settings I used for PLA:
Model: RepRap
Nozzle: 0.4mm
Filament width: 1.75mm
Extruder temperature: 205 deg C
Bed temperature: 60 deg C

Free 3D object repositories

There are many sites that have 3D objects that you can print on a 3D printer. Usually it is a case of downloading the appropriate file and then using the Slicer Software (discussed above) to create the G-Code. The following are a few sites that have 3D files available.

[Please check terms of use etc.]

3D CAD Software

If you are looking to create your own models then you will need some 3D CAD or design software. There are two different 3D design applications that I have used with Linux.
The first is Blender which is a 3D modeller. This is popular for creating 3D visual objects, such as characters used in games and animations. The models can then be exported for use in a 3D printer.

The second is FreeCAD which is a full 3D CAD application. This is particularly useful if you want to create parts that need to interact as you can specify the exact dimensions. Learning FreeCAD is quite a steep learning curve, but well worth it. FreeCAD is available for Linux and works on the Raspberry Pi 3 (although I've only tried with small objects, memory will be the main limitation).

If you are looking to learn FreeCAD then I found this FreeCAD Video tutorial by j16out to be useful.

After creating a 3D object then you need to export it as an STL Mesh file which can be opened in the Slicer software.

Summary

I haven't done much with the printer so far, but I'm happy with the results so far.

The combination of Cura and FreeCAD works well on Linux (except the Raspberry Pi for Cura).