What can you repair with 3D printing?

This article was written as part of the RE.FAB TOUR project, funded by the Walloon Region. Stay tuned for regular articles on 3D printing for repair. Find the whole series here, as well as resources for further study and training!

 

A gear is broken? A plastic shell or clip is impossible to repair? A small part necessary to the functioning of the object has come loose and is lost? A replacement part is not available, or is too expensive? In many cases, 3D printing can mean a successful repair!

 

See our gallery of 3D repair examples here

 

Let’s start by remembering that 3D printing is not a miracle solution. The technique can be useful in certain cases, but not everything can be repaired using 3D printing. In this article, we attempt to sketch out a classification of what is – and isn’t – repairable with this technique. It also accompanies our gallery of examples of parts repaired in 3D, which will continue to be added to as the RE.FAB Tour progresses.

 

Before getting to the heart of the matter, we’d like to make it clear that we’re using the term 3D printing to refer to FDM, or fused depositiontechnology , which is the most accessible, both financially and technically. It’s also the most widespread for personal use and in Fablabs. Other technologies also exist, and may be relevant options for overcoming certain limitations of FDM printing. We’ll come back to this in a future article.

 

Now you can get started! A part has broken, for example the shell of a remote control, and repairing it using 3D printing seems like a good idea. The first thing to do before you start looking for or designing the part is to think twice about whether 3D printing is necessary.

Perhaps the object can be repaired in another way, using glue, a clamp or a screw. Wouldn’t a well-placed piece of tape do for my remote control? Maybe 3D printing a replacement part isn’t such a good idea! The properties of the materials available for 3D printing are limited, and don’t allow us to reproduce every type of part.

When considering 3D printing, it’s important to make sure that :

• Part is not in contact with foodstuffs
• The part does not play a safety-critical role
• Part is not subjected to high temperatures
• The part fits in one hand

If you answer yes to these four questions, the repair is – a priori – eligible for 3D printing.These are, of course, general criteria.A negative answer to any of these questions implies a complicated repair, but not an impossible one! Some materials can withstand high temperatures, and some 3D printers can print particularly large parts.

In concrete terms, what parts correspond to these criteria? Here’s a preliminary classification of parts repaired in 3D. All examples are taken from our gallery.

• Reproduction/adaptation of a part not essential to the object’s operation
  This is one of the most common cases. A support is lost, a shell is broken.It’s annoying, but the part doesn’t prevent the object from working.The original spare part is often non-existent or hard to find. As in the case of these little pins, used to hold the hood of a bicycle helmet, one of which was lost.

• Reproduction / adaptation of a part essential to the functioning of the object
  This is the other most common case. Here, the broken part is essential to the functioning of the object. It has a function, a mechanical role. Particular care must be taken when redesigning to ensure that the part can perform its function. Here again, spare parts don’t always exist. Sometimes, the appliance is too old and the part is no longer sold. Sometimes, the broken part is part of a larger, more expensive or more complicated assembly to repair, as in the case of this microwave turntable gear, where the only alternative would be to replace the entire motor block.

• Reinforcement / creation of a repair part
  In this case, the broken part is not directly reproduced. The printed part has no equivalent in the broken object, but will enable it to be repaired. For example, when a part is broken due to a design weakness and needs to be completely redesigned. Or when the printed part enables the object to be repaired using another technique. This was the case with a vacuum cleaner whose watertightness was compromised by a break in its lid. The 3D part, following the contour of the lid at the point of breakage, enabled the lid to be glued back on and reinforced.

Apart from these repair categories, 3D printing can also help in a more indirect way to extend the life of our objects:

• Personalization
  This category is closely linked to the possibilities offered by 3D printing: the idea here is to take advantage of the need to repair the object to transform it, to make it your own, to personalize it. This can apply to the restoration of a vintage or decorative object, but also to more functional repairs. A simple example? A mug with a broken handle that can be discreetly repaired… Or less discreetly!

• Tools for repair
  A little apart in our classification, 3D printing also offers interesting possibilities in a more indirect way, for the creation and adaptation of useful tools for repair! Typical examples are the spudger, a thin, quickly-worn tool for opening clipped parts, or the screw tray, for sorting and organizing all the screws removed during disassembly. Other more specific and useful tools can also be 3D printed, such as a watch clip, or this tool for detaching a Senseo coffee machine float for replacement!

This rather rough classification gives an initial overview and illustrates the different forms that 3D printing can take in repair. It is not, of course, exhaustive. With a little creativity, the list of feasible repairs is endless!

It’s also important to bear in mind that just because it’s technically possible to repair an object using 3D printing, it doesn’t necessarily make sense to do so! There are often alternatives, whether through the use of an original replacement part, or through a tinkering solution. And using 3D printing requires time, skills, and has an economic and environmental cost! The decision whether or not to repair using 3D printing can therefore be based on criteria other than just its feasibility: economic and environmental criteria, but also and above all emotional or didactic criteria. Quite often, beyond the technical aspects, the attachment we feel for the object and the pleasure we find in repairing it will be two essential elements that drive us to repair. This also applies to 3D printing!