The process of prototyping is key to the development of any new product, and now with 3D printing you’re able to roll out prototype after prototype without having to employ an expensive third party.
This not only makes the process of prototyping faster – it saves money, and ultimately enables you to get a product to market more quickly.
3D printing makes sense for the product design and engineering industries, where time really does equal money, but closer to home – or actually in the home – there’s an equal number of amateur product designers out there creating new projects and innovations.
Having a printer in the home or office opens up a wealth of opportunities to experiment – but while 3D printing certainly makes prototyping easy, there are several issues associated with it.
First and foremost is the printer itself – can it print at a high-enough quality to give you a good idea of what the final product will look like, and will it also convey how that product will function?
The design process takes time, so when you start prototyping on a 3D printer it’s a good idea to start with fast, low-quality prints. This way you can the check the product’s dimensions. Then, as the design process continues you can tweak the printer settings to increase the quality.
Obviously if you’re trying to turn around several prints in a day, you need an easily flowing material that can be extruded quickly; however, you also need a material able to support fine detail and accurate printing.
The traditional prototyping material choices have always been ABS and PLA. ABS is typically used by professionals, due to the material’s strength and quality of finish, while PLA is better for the home enthusiast as it’s more forgiving, produces fewer fumes and is better suited to home 3D printers.
In the world of real products, PLA has traditionally been used for food packaging and medical implants, chosen for its low toxicity and biodegradable properties. This gives some idea about this particular plastic’s characteristics aside from being an ideal material for 3D printers. Meanwhile ABS is used when an item needs to be durable; one of its best-known uses is LEGO.
PLA’s big advantage over petroleum filaments such as ABS is its far lower toxicity level and biodegradability. In real terms it produces fewer fumes so is safer to be around during printing. This means that you can have the 3D printer on your desk while you work – but even so, you should always print in a well-ventilated area.
When it comes to PLA reels, however, not all filaments are the same – the difference between manufacturers is huge.
The latest PLA from Verbatim is a next-generation material and, by using a selection of additives in the plastic mix, they’ve produced a filament that retains low toxicity yet increases print accuracy and functionality.
Verbatim’s latest PLA enhances an already excellent material, and the changes in formula enhance the filament’s characteristics to make it a viable replacement for ABS in many stages of the prototyping process.
During the design process it’s not uncommon to produce tens or even hundreds of test prints, and these are used to refine and optimise designs. Having a printer on your desk therefore makes sense, and PLA is the perfect filament partner. It requires a lower hot-end temperature of 200–220ºC, compared with ABS at 220–245ºC.
The flow of Verbatim’s PLA filament at this temperature is superb, and will enable you to run your printer at high speed and still produce good-quality prints – something that many PLAs will falter at when it comes to the quality of flow. The quick printing properties, along with accuracy, make it the ideal material to use when building a DIY drone.
As the design process continues and you require higher-quality and functioning prints, the extrusion speed can be reduced and high detail can be achieved.
Although ABS is favoured in pro labs for prototyping, the cost and quality of these printers is obviously higher than the machines that most of us have in our homes or offices. ABS is used by professionals for its print quality and strength, but these properties don’t necessarily translate well to home use.
If your printer is well calibrated and maintained then ABS is a perfectly good material, but the likelihood is that you’ll need to adjust your printer or the print settings depending on the structure of your model. Warping with ABS can be an issue for the home printer, and while the issue also affects PLA, this is not to the same degree. Verbatim’s mix reduces the effects of warping so that it is almost non-existent.
This lack of warping is reflected across other aspects of the print quality when it comes to avoiding common problems. Printed features such as screw holes, gears and connectors show great accuracy and consistent results, which means that there is far less likelihood of error during the design process.
As the drone has four arms, the overall scale of the vehicle will be much larger than the print bed of an Ultimaker 2 Extended. To get around this problem the drone is split into parts, and each is printed separately. Accuracy is paramount even for a prototype, as screw holes will need to be the right diameter and align perfectly so that the craft can be easily bolted together.
If you’re working close to the printer, the fumes from filaments can be an issue. PLA’s toxicity is far lower than that of ABS, and during the print process there are noticeably fewer fumes.
Usually PLA has a slightly sweet smell, but Verbatim’s PLA hardly smells at all. However, always use it in a well-ventilated room.
Strength without brittleness
One of the biggest issues with PLA is that the material is brittle, and this is why many professionals don’t like to use it for prototypes. If you are just printing figures or a small single-piece print, this brittleness really isn’t an issue – but if you need to bolt several parts together in order to build up your print, or need the product to support weight or force, then a strong material is essential.
The additives produce a slightly softer PLA than normal, although to the touch it feels exactly the same as any other PLA filament. However, this slight softness increases the overall strength and reduces the brittle characteristics. Creating an item with Verbatim filament and pressing the part in your hand shows that the material allows flex in the same way as ABS; do this with the same part printed using another PLA and it is likely to snap.
When used to create the DIY drone, the material has enough give to cope with the different forces applied during flight testing, and enough strength to survive an inevitable crash landing or two.
This lack of brittleness also makes it far better for finishing, and closer to ABS when it comes to quality of finish. As with ABS, the edges and surfaces can be finished with a knife and sandpaper.
Verbatim’s PLA is a step forward as a material for prototyping: its characteristics such as low toxicity, strength, and finishing and biodegradable properties make it a viable prototyping material choice, not just for early test prints but as a material to use throughout the design process.
As the testing process continues, the development of the drone advances; weight and balance issues are corrected and the electronics are gradually routed into the structure.
Using a material you can rely on to print accurately without warping will save you time, especially when you need parts such as screw holes to align perfectly.
Material expansion is a common issue, but with the Verbatim PLA there is none. This means that if you make parts designed to slot together, they will.
Early prototypes might highlight design considerations for the electronics, but it’s only when you add the wiring that you can check everything will be exactly where you intended.
Although not the most elegant solution, simple bolts are a great way to construct early prototypes if the material can cope.
Getting the electronics to sit perfectly within the model prior to building the external structure is essential. You also need to ensure that everything can be secured.
Strength and weight are major considerations, so a material that can contribute to a weight-saving design is essential.