3D printing may seem like a fairly recent innovation, however it’s been around for longer than you might perhaps imagine. The first 3D printers appeared commercially in the mid 1990s, but priced in the region of £75,000 they certainly weren’t cheap – you were in Ferrari and Porsche territory.
The technology was developed in the 1980s, Chuck Hull being accredited with demonstrating his SLA-1 printer as the first commercial example some 34 years ago on March 9th. His intention was to develop a machine that would be capable of speeding up the time it took to create prototypes as using a one-off machining process was expensive
in terms of both time and money; the ability to print an item in just a few hours represented a major breakthrough as you can imagine.
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I’ve wanted a 3D printer ever since they became commercially available at sensible money. Whether I really need one is another matter, nevertheless I decided to start investigating. Having almost zero knowledge on the subject of 3D printing, before contemplating splashing any cash, I thought it would be wise to understand what was available and, more importantly, what would be suitable for my intended use. Researching topics is so much easier today thanks to the Internet, but you do need to filter out the rubbish posted by those who feel the need to have an opinion on everything, even when they’ve never owned or used the item for which they’re offering advice.
I very quickly established there was a vast and confusing array of 3D printers available, from those looking not unlike a microwave oven to others for self- assembly – Heath Robinson affairs – often looking like they were made from Meccano and string.
Adding to my confusion was the price range, which was significant, so I decided I needed to talk to someone who actually owns a 3D printer and, fortunately, a couple of my mates do. A brief chat served to establish even more confusion though, as there’s also a choice of materials to print with, and not every hobby grade printer is compatible with all materials.
PRINTING WITH SUGAR
Two common materials available in many colours are PLA (Poly Lactic Acid) and ABS (Acrylonitrile Butadiene Styrene). I understand that most hobby grade printers use a process known as FDM (Fused Deposition Modelling, also known as FFF (Fused Filament Fabrication). Here, thermoplastic is melted and printed through a heated nozzle in layers.
And this is where a surprise came; almost all printers will print PLA, a bio-degradable thermoplastic aliphatic polyester that can be produced from corn starch or sugar cane. It’s safe to use, gives a glossy appearance to the printed objects and, being sugar-based, has a pleasant odour. PLA has some downsides though. Due to its low melting point it can warp in high temperature applications and even crack. ABS is tougher but needs to be printed on a heated print bed at higher temperature and the machine requires ventilation as the fumes are unpleasant.
So, depending on what you want to print, it’s important to research the capability of your intended printer as not all hobby 3D printers can use both types of printing filament. To further confuse things there are many other materials than can be printed on industrial machines – Nylon, ceramic, resin and even metals such as stainless steel, titanium, silver and gold.
EXPLORING THE THINGIVERSE
So it wasn’t going to be quite as easy as I initially envisaged and then I also realised I had to learn how to design objects to print. “Look on the Thingiverse” advised my mate Rob. “Thingi what?”
Thingiverse is basically a repository of more than 1.6 million designs you can download (in the main, for free) as diverse as a replacement kitchen sink plug to a full-size, playable electric guitar body and neck.
You don’t need to learn how to design them, just get to grips with the simple software package for your chosen printer, download the thing, import it and press print. Have a look at www.thingiverse.com but don’t expect it to be a quick peek as seeing what you can make will become addictive.
This was sounding more like it. I could play straight away and barely have to read an instruction manual. Even better, there’s a facility on Thingiverse to customise a ‘thing’; a sort of halfway house to designing your own which will help introduce the various processes required.
The three components that make up the Enya .09.
I couldn’t help myself… despite not actually owning a 3D printer yet, I started downloading numerous designs to build a back catalogue of future projects. My modelling interests range from multirotors, FPV aircraft and simple rudder-only models to 1/3-scale behemoths; I quickly located some Mobius / Foxeer / Fat Shark camera mounts and LED holders for my FPV racers.
Another find was a great print of a small i.c. engine (much like an Enya.09); perfect for putting on my e-powered retro conversions (I actually got my mate to run a few off).
A recent development is fully 3D printed flyable models. I would imagine that this is beyond the scope of a hobby printer and after reading that some materials can deform in heat I guess you’d need to be careful where you store your pride & joy so it doesn’t end up looking like something from Salvador Dali’s mind.
Even more amazing is the capability of a company called Apis Cor – they can 3D print a house; not a dolls house, but one you can live in! Printed on site using a high strength construction mix based on concrete, the self-supporting walls and partitions of a 3 bedroom-house can be printed in 2 – 3 days by a 2-man team, almost ready for the finishing works with virtually no waste or rubbish produced.
I digress, if it’s almost time to get out the credit card then remember there are options to consider; ready-made or DIY, single or multi-filament capable, PLS / ABS / TPU (Thermoplastic Polyurethane – more in a moment).I established that PLA has a wide range of applications and is the hobby printer’s material of choice for items such as camera mounts, multirotor frames and model aircraft cockpit detail; in fact most things that don’t need maximum strength. Additionally it’s bio-degradable, has low toxicity, and is great for items that need a high level of detail.
For more robust applications ABS is the preferred material, although it has some downsides. There’s a tendency to produce slightly rounded corners (when sharp edges are required), and the printed surface that’s in contact with the printer base plate can warp. This tendency can be reduced or even solved by using a heating printer bed along with strategically placed cooling fans if required.
During my voyage of discovery I found another material, TPU (Thermoplastic Polyurethane), which is flexible and has a much higher abrasion resistance than ABS or PLA. It would great for printing landing feet and motor protection covers for multirotors, or wing tip skids for aircraft to prevent damage when the wind selfishly messes up your cross-wind landings on tarmac.
Multirotor applications are many and varied, prop-guards in this case.
3D printers can vary greatly in price, and just because one model is twice the cost of another, similarly specified example, doesn’t necessarily mean that it will be better. After establishing the materials you want to use, you then need to determine the maximum size of printed objects that will be required so you can choose the ideal print bed size.
Rob also advised me of other considerations when selecting a printer, namely the speed, resolution and layer heights it can print at.
For hobby printers, prices vary from around £150 – £1000 with many, very well featured models (in both kit form and ready-to-go) retailing for £250 – £500. If you have the skill (and confidence) to assemble one then, generally speaking, you’ll end up with a higher specified machine for your money. Last year I built a CNC router from a kit and although initially thinking I may have overstepped the mark after opening the box and unpacking a myriad of parts, by methodically following the build manual and referring to YouTube videos I quickly ended up with a working and reliable machine, with the bonus of a 40% saving over the equivalent ready-to-go model.
There are a good range of 3D printers available and there’s also a great choice on Amazon. Once you have a few potential candidates, check out the online reviews; second thoughts, check out lots of online reviews and average out the comments, just to be on the safe side.
After lots of research and chatting with mates who regularly 3D print items, I’ve come to the conclusion that modern 3D printers in the main appear simple to use; even the cheapest hobby printers produce usable results. To get the best out of the printer you’ll ultimately need to get some compatible CAD software to design your objects, but this isn’t necessary to start with and, as mentioned, Thingiverse has a vast catalogue to get you started.
Have a look at www.reprap.org – a great information resource for DIY builders and also for freeware CAD packages. I’ve realised there are many reasons to want a 3D printer and get those creativity juices flowing, and would imagine it could even become a hobby in its own right. I’m sure I’ll find many uses for it. ✈
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