3D Printing

What is 3D printing?  Basically this involves building a 3D shape by building up layers of material.  The material is most often a plastic (PLA, ABS) filament that is extruded through a heated nozzle but all sorts of materials can be used including filament fused with wood or aluminum.

When I first got into 3D printing it was to meet a need … printing special tools for working on dirt bikes, specifcally I wanted fork seal sliders.  I never expected it to be a hobby in itself but when I started printing, I found the process of designing something and then printing it to be enjoyable and rewarding.  I soon fell into the “what can I print now” trap and before I knew it I was trying to fit a 3D print into solving problems that really didn’t need it.  For example, I installed a dishwasher in the kitchen but the mount tabs were about an inch below the counter top so I started designing a spacer in my head.  While taking measurements to model the spacer, it occurred to me that I could simply take an inch thick piece of wood, screw it into the counter top and then screw the mount tabs to the wooden spacer, job done!

This leads to another aspect of 3D printing that seems to be often overlooked – 3D modelling.  While even entry level printers can be quite capable of printing some good quality, complex parts, step 1 of any print is creating or obtaining a 3D model of the object to be printed.  Through my experience of studying and working in engineering I was able to create models with relative ease but even then it took me a little time to find suitable 3D modelling software – I settled with Onshape.  Of course it is not necessary to learn how to model in 3D to make use of a 3D printer, there are many sites that offer 3D models (usually STL format) for download and usually have many free models – yeggi and thingiverse spring to mind.  Some printers even come with a 3D scanner but I have not yet tried using one.  I suspect that they would be good for things like Yoda busts or figurines but for tools or prints where strength is important, I doubt they would be of much use.

Once you have a model, step 2 is to use another piece of software that slices the model into layers and converts them into instructions that the 3D printer can understand.  Again there are several options and the higher end printers often come with proprietary software, I have been using the open source Cura software that is extremely powerful and yet fairly easy to use.  While a 3D model defines the shape of the object, the slicing software defines the way it is printed (and creates the G Code instructions for the printer), this is where you would set things like wall thickness, infill pattern, amount of infill, layer thickness, printing speed, etc.  For parts that will be ‘used’ these settings can be critical, the fork cap wrench for example needed thick walls and high infill percentage to achieve the required strength.