Ailothaen's Notebook

An introduction to 3D printing

Ailothaen — Thu, 18 May 2023 16:32:00 +0100

When I started my first project of 3D printing an object, I tried to look for information about 3D printing in general, and I struggled a bit. This article aims to be an introduction to 3D printing for anyone wondering what it is, and who might want to make some creations.

Over the last few months I have been drawn into the world of 3D printing (somewhat unexpectedly: it all started with an object I wanted to make...). I started printing things on printers I had access to in a fablab, and then I ended up buying a 3D printer of my own.

When I started my first project of 3D printing an object, I tried to look for information about 3D printing in general, and I struggled a bit. In fact, 3D printing is a really broad field, and I could not find a single resource that answered all the questions that a complete beginner who knew nothing about 3D printing, like me at this time, had.

So this article aims to be that resource: an introduction to 3D printing for anyone wondering what it is, and who might want to make some creations (whether with a printer of their own, or by paying someone to print the object). I will not go into too much detail (because then we would get into very specific topics), but by the end of this article, you should already have a much clearer understanding of the subject.

"3D printing": what are we talking about?

Before we start talking about "3D printing", we need to know what exactly we mean by this term.

3D printing is also called "additive manufacturing". This means that parts or objects are made by progressively adding material, unlike other techniques such as moulding, deformation or subtractive manufacturing (we start with a large block of raw material that we progressively cut to get the object we want).

You might think that 3D printing is something very recent, and that it refers mainly to the production of small plastic objects. But actually, it is much more broad than that: 3D printing, which has been around for a few decades now, began with industrial applications (prototyping, production of specific objects, etc.). For example, here is what can be called a "3D printer" which uses concrete:

(from Wikipedia)

We can also mention medical prostheses (especially dental crowns). Recently, we have even seen companies using 3D printing to make... houses (by superimposing layers of concrete).

3D printing techniques

There are several ways to do 3D printing. Here are the most common ones:

FDM

FDM stands for "fused deposition modeling". This is the most common technique used by individuals, and is often the one you think of directly when you hear "3D printing" (even if it is only one of the techniques). This is the one I am going to talk about in this article.

You probably already have seen it in a timelapse video: an FDM print consists of starting with an empty tray, heating a plastic (most often in the form of filament) so that it becomes liquid, and making it come out of a print head that can move in all three axes (width, depth, height). Progressively, the printer builds an object by depositing the plastic.

Here is a timelapse video of an FDM print:

FDM printing is relatively easy to implement, and is not very expensive (both for the price of the printers and the materials), hence its success.

SLA

SLA (stereolithography) is another printing technique, also relatively accessible although less common.

Here, the material is a resin in liquid form, which at the beginning of the printing process is located in a tray. The tray is dipped into the tank, and a laser targets specific areas on the tray to solidify the resin and create an object. As with FDM, the printing is done layer by layer... a difference being that here, the printed object is "upside down".

Here is a timelapse video of an SLA print:

SLA printing is more difficult to master than FDM printing, but can produce more detailed and therefore more beautiful prints, especially for decorative objects.

Other techniques

The other techniques are more restricted to industrial situations, so they are less common.

For the most part, they are derivatives of the two methods mentioned above; for example, Selective Laser Sintering (SLS) is similar to SLA, but instead of liquid resin, powder is used.

Those who are curious can read this article or this one.

FDM 3D printers

There are many different brands of FDM 3D printers, and even more different models. However - and although some strange models do exist - you will see that all models are actually looking very similar, and have the same external appearance. This is normal, they are composed of the same elements (just like a laptop is composed of a keyboard, a screen, a touchpad...)

In fact, contrary to what one might think, the difference in print quality between an entry-level printer ($200-300) and a high-end or even professional printer (where one is closer to $5000-10000) is not really that big: where high-end printers will stand out is more on "bonuses" and secondary features that will simplify the work of the user (automatic alignment, double print head to have several colours at the same time, customer service available 24/7...)
Thus, with an entry-level printer, you will be able to make prints as good as other more expensive printers, but you will spend more time tinkering with it and adjusting it so that the print is successful.

Let's go through each of these elements in detail to understand what they are used for.

Axes

As you might expect, on a 3D printer there are... 3 axes (that's why we call that 3D 😄) on which the print head can move: width (often noted X), depth (often noted Y), and height (often noted Z).

(from here)

The X axis is the same on most printers: the print head is driven by a belt on an axis.

For the Y axis, there are two different types: either the head moves (in which case the printer is cube-shaped), or the bed moves in depth (in which case the head does not need to move). In general, X and Y moving heads are found on more expensive printers, although there are exceptions.

For the Z-axis, again there can be two possibilities: either the print head (and the X-axis with it) moves up, or the bed moves down.

Here is another example of a printer with a Y axis on the head and a Z axis on the bed:

Print head and extruder

The print head (also called "hot end") is where the plastic filament is heated, and then becomes more malleable and can be deposited on the printed object. It ends in a nozzle, which has a hole of usually 0.4 mm in diameter. It is possible to change the nozzle to get either more precise prints (smaller holes) or faster prints (larger holes)

The extruder is the part before the head, which will push the filament in (with a gear).
Depending on the printer, the driver can either be located directly above the head (called "direct drive") or offset elsewhere (called "bowden"). Both types have their advantages and disadvantages.

Most printheads contain Teflon (PTFE). This makes them easier to manufacture, but it prevents the use of some (less common) plastics that require temperatures above 260°C. This is something to consider when comparing printers.

Bed

The bed is the support where the object will be printed. It can be made of glass, metal or PEI (Polyetherimide)

Some types of plastics need heat to "stick" to the bed when the first layer is printed. For this reason, beds can be heated, usually to at least 60°C.

Materials

We have seen that FDM printing involves taking a plastic filament, and heating it to lay it on an object to be manufactured. As you might expect, there is not just one type of plastic: there are a good dozen that can be used, each with its own characteristics (strength, durability, colours, price, etc.). And there are even filaments that are not entirely made of plastic, but which are a mixture of plastic and something else: for example, there are plastic/wood mixtures, which make it possible to print an object that looks like... a wooden object.

Here is an overview of the most common plastics:

Polylactic acid (PLA): THE classic 3D printing material, because it is cheap, available in lots of colours, and easy to print (because yes: some plastics require more complicated settings, or even quality equipment). It is also good for the environment, as it is made from corn starch. It is very suitable for most decorative and functional objects, but if you want to "do better" (especially in terms of durability, UV tolerance, etc.) and have specific requirements, you can pick something else.
Acrylonitrile butadiene styrene (ABS): It is known by the public because of Lego bricks, which are made with this plastic. It is a little more complicated to print than PLA (notably because it requires higher temperatures and has a tendency to come off the plate during printing - this is known as warping), but it has better mechanical properties (resistance to impact, temperature, etc.) which make it more interesting for certain applications, such as phone covers for example.
TPE, TPU, TPC: a family of plastics which have the particularity of being flexible, therefore suitable if a more "elastic" object is required
Polycarbonate (PC): a very strong plastic that is slightly transparent (this is what I printed the Ori I linked to at the beginning of the article). I jokingly call it "the royal plastic" 😆. It is more expensive than PLA or ABS and needs very high temperatures to print, so you cannot print it on all printers.

Some people make comparison charts of the different materials:

How do we print something?

Modelling the 3D object

First of all, you need to get a "schematic" of the 3D object. There are three possibilities:

Either you model the object yourself, with 3D modelling software (Blender, Fusion 360, etc.). This is a complex subject and this article will not talk about that
Or – lucky! – someone has already modelled the object and offers it for download
Or you have a 3D scanner that produces a 3D model of the object.

Using a slicer

Once we have our 3D modelled object, can we give it to the printer to start printing? Of course not... it's not that simple.

You have to know that a 3D printer, in fact... is quite dumb. It does not know how to do anything by itself and needs to be told exactly what to do. And when I say "exactly", I mean things as simple as :

moving the print head a certain number of centimetres on a certain axis
pushing out plastic (or not)
heating the head or the platen to a certain temperature
...

The printer actually expects "gcode" files. These are files that describe EVERY action the printer has to do. Here is a gcode example:

G92 E0 ;Reset Extruder
G1 Z2.0 F3000 ;Move Z Axis up
G1 X10.1 Y20 Z0.28 F5000.0 ;Move to start position
G1 X10.1 Y200.0 Z0.28 F1500.0 E15 ;Draw the first line
G1 X10.4 Y200.0 Z0.28 F5000.0 ;Move to side a little
G1 X10.4 Y20 Z0.28 F1500.0 E30 ;Draw the second line
G92 E0 ;Reset Extruder
G1 Z2.0 F3000 ;Move Z Axis up
G92 E0
G92 E0

To produce this file, we first need to import our model into a specific software, called a slicer.

Like 3D modelling software, there are many slicers. However, there are two that are widely used: Cura (developed by Ultimaker) and PrusaSlicer (developed by... Prusa). Both companies originally made these slicers for their own printers, but as all FDM 3D printers work the same way, it is possible to use them with any other brand and model (as long as you follow the manufacturer's instructions)

Slicers have a lot of parameters to adjust. The ones that are most often changed are:

the temperature of the print head
the temperature of the plate
the filling of the object: hollow, empty, or between the two
the use of supports (I will talk about this later)
the use of the fan
the printing speed

These parameters depend usually on the material you are using. Pre-programmed profiles exist to select the right values according to the materials and the printer model.

An example? Of course! Here is an Ori that has been run through a cutting software (here Cura). The software show us, layer by layer, the application of the material on the object, and tells us how long it will take to print. The colours on the object tell us "what the plastic applied here is for": red for the outer walls, green for the thickness, orange for the filling...

What does "object suitable for printing" mean?

This is maybe the point that confused me the most when I discovered 3D printing. I used to hear about "models suitable for 3D printing" and I wondered why some things could be printed and others not.

To understand the problem, I will show something that is impossible to print. Can you find out what the problem is? (if you read the article well, you should easily find out 😄)

Answer: as we have seen before, an object is printed bottom-up. When we get to the "bar" of the T, the head will start to print it... but there will be nothing underneath to hold it! So the plastic will fall off and you will not be able to print the "bar".

The solution is to configure the slicer so it generates supports:

But removing the supports is a very tedious operation. In the case of the T, it is easy because the surface is flat, so you just need to file it. But as soon as you get to more complicated things like characters...

... have fun removing all the supports without damaging anything else!

In these cases, you may have to be clever to avoid using supports as much as possible. You can try rotating the model in the slicer to print it at a different angle (the aim being to get as close as possible to a pyramid shape). In the case of the T, you can just turn it upside down, so that the "bar" is at the bottom.
You can also change the parameters of the supports in the slicer, so that there are fewer of them (which always come with the risk of failing the print...).

Sometimes the best solution is to edit the model to cut it into several parts, which can then be assembled. For example here, it was impossible to print this coin without needing supports on one side (which would have been almost impossible to remove without damaging the side). The solution was to cut the coin in half (like a sausage!) and then glue the two sides together after printing.

Going further

The all3dp website is a goldmine: almost every aspect of 3D printing (not just FDM) is covered in an article.

Sites where to find 3D printing models to download:

The r/3dprinting subreddit and its very useful links at the top of the page (wiki, buying tips...) is also interesting.

My take on NFTs

Ailothaen — Sat, 13 Nov 2021 23:59:00 +0000

In recent months, the "innovation" of NFTs has been shaking up the world of culture, and more particularly the artist communities. My opinion on this: NFTs applied to the art world bring nothing new and innovative, and are just a trend that will fall out of fashion within a few years.

In recent months, an "innovation" has been shaking up the world of culture, and more particularly artist communities. For several months now, NFT (Non-Fungible Tokens) have been spreading in these circles, as they are seen as a way to buy and sell artworks. Reactions are very divided: some present them as a great revolution in the art world and are very enthusiastic, while others see it as the incarnation of the evil, with all its problems. But generally speaking, all artists have heard of it, and almost everyone has an opinion on it (positive or negative).

As I looked into the technical aspect of NFTs, and I therefore have my opinion on it, which I will elaborate on: NFTs applied to the art world do not bring anything new and innovative, and are just a trend that will fall into disuse - or at best be relegated to a niche market - within a few years.

NFTs: what they are, and how they work

You may be familiar with the concept of blockchain. I am not going to explain it in detail here, as it is a technical and a long topic, which actually deserves a dedicated article (maybe I will do one).

To keep it simple, a blockchain is a kind of database, where we will add blocks of data one after the other (think of an Excel sheet: there is a defined number of columns, and a virtually infinite number of rows, and each time we add data, we add a row). The particularity of this database is that it is impossible to modify a data block once it has been written (not even a single character!). The point is that the database can then be distributed publicly, and anyone can read it and add new data. It is therefore a decentralised database (as opposed to a centralised database which is managed by a single entity or company).

Cryptocurrencies, such as Bitcoin for example, are based on the concept of blockchain: each block of the Bitcoin blockchain represents a transaction, and by reading the entire blockchain, a digital wallet manages to "reconstruct" the entire Bitcoin monetary system, and thus calculates how much we have on our "account". So, in the context of Bitcoin, what we will write in the block is an instruction like "account 84df8d7bd7438 sends 1 bitcoin to account be560c42793b29". (Of course, you cannot create a block saying "I give myself 999999 bitcoins", there are verification mechanisms to prevent this)
Why do cryptocurrencies use a decentralised system? Because not relying on a central authority can be a huge advantage: you are not dependent on it, you are not affected by its possible failures, and it is much harder to compromise the system (since there is no longer a single organisation to hack). Since cryptocurrencies were originally intended to be an alternative means of payment independent of a central authority (and still are), the blockchain solution was therefore obvious.

What does this have to do with NFTs, you might wonder? NFTs are also based on the blockchain concept. The only difference is that the instruction we are going to write is something like "Mr John Doe bought the artwork n°2d82837e from Mrs Jane Doe, and is now the owner of it.".
A particularity of NFTs is that they are bound to an identifier (which can represent an object, material or not), and that there can only be one NFT for each identifier, which is therefore unique (hence the "non-fungible"). This is therefore very useful for "attaching" a unique NFT to a specific object.

Summing up, then, NFTs are a method of certifying that one owns an item, using blockchain technology instead of relying on a certified actor to deliver that certification.
That's it. That's "just" it.

In the context of works of art, NFTs are used as "title deeds" to prove that one is the owner of a work of art (but not only, as we will see right after...)

We are the "owner" of the work... and then?

Lately, we have seen a wide variety of unexpected, even surprising, things being sold through NFT. Artists are selling their fan art with NFTs, Reddit is selling unique avatars through NFTs, already-written tweets are being sold through NFTs, and there are even internet memes sold by NFT, such as this famous photo sold for $74,000:

But in practice, what does it mean to "buy a meme" or "buy an avatar"?

It means that when you are going to buy this image, it will be written in a blockchain that you are the owner of this image. Better yet, the sole owner, because NFTs are by design unique (it will be impossible to create another record referencing the same image without "undoing" the previous one). At this point, you are probably thinking "what is the point of being the official owner of a meme or tweet?" Well... not much. Being the owner of a digital object in NFT, in absolute terms, does not prevent this file from being able to continue to circulate on the Internet, and to be copied at will (as a proof, I posted the meme of the girl just above, even though I am not the owner...).
Even if we accept that the owner of a work bought by NFT is recognized as an owner from a legal viewpoint (which, to my knowledge, is not yet the case) and that he does not want this image to circulate on the Internet anymore... he can always take legal action, but can you imagine doing that repeatedly until the image disappears completely from the Internet? Especially since we know very well how the internet tends to react when something is censored...

In fact, in the end, the only use of buying an NFT in this context is just... to be able to show off. To be able to say "I own that tweet!". Since it does not prevent unapproved reuses of this thing, either technically or legally.
Another use that some people see for NFTs is to speculate: to buy title to property in the hope of selling it for more later. But since NFTs do not really have any value apart from what you want to give them (yes, because even crypto-currencies have intrinsic value: their primary purpose is still to serve as a payment unit. But NFTs? ...), it is a very risky investment and tends to attract scams.

Useful for small artists? Maybe, but...

From a more mundane perspective, one could argue that NFTs can be useful to small creators (typically, the average artist posting on Tumblr or DeviantArt). NFTs could provide irrefutable proof that someone who has paid for a commission is indeed the owner of the work, and can therefore do whatever they want with it: this would therefore be useful, especially if the author of the work disappears or comes into conflict with the buyer and decides to "steal" it.

But, beyond the problems mentioned above, there is also another major problem with NFTs. Remember, I said earlier that NFTs are, by nature, a decentralised technology. This implies that anyone can potentially make a write to the blockchain, and write whatever they want... so the problem easily appears. Then, what is going to stop someone from taking an image (let us say that one for example) and writing in the blockchain that they are the owner of that image, unilaterally?
Or even worse: let us say an artist does not sell their artworks in NFT, but someone decides to write that they are the owner of that work, without the artist's consent. Do not laugh, it is a problem that is clearly recognised and known today, so much that it led DeviantArt to develop a tool that alerts the author of a work if their work ends up on an NFT buying/selling platform:

That problem could be partly solved by establishing trusted actors, whose "word" would be more valuable than anyone else in the NFT ecosystem. But this also does not guarantee that this kind of abuse will not exist (it depends on the platform's willingness to moderate its content and check that works are not illegitimately offered for sale), and it has the paradoxical effect of reintroducing centralisation into a system that was intended to be decentralised.

This leads me to...

Where is the real innovation in this?

Some people present NFTs as a revolution in the art world, arguing that it will change the way artists make a living, the relationship that "consumers" have with art...

However, I do not agree with this at all. Indeed, if one wants to certify something digital (like a sentence saying that someone owns some item...), it has been possible for decades, thanks to cryptographic certificates. In the digital world, we need to certify a lot of things, so cryptographic certificates are massively used. By the way, if you are reading this very web page in HTTPS right now, it is thanks to a cryptographic certificate! It guarantees that the encryption key used to encrypt HTTPS traffic is actually mine and not someone pretending to be me.

In fact, the only difference that NFTs make is that this certification is no longer dependent on one organisation, but works in a decentralised way, which avoids some of the problems I mentioned above. But given that, as said in the previous section, we will still need trusted actors, it is a snake biting its own tail, and so the value of a decentralised system falls almost to zero.

But in the end, are NFTs something to throw away? Would not it be useful in some contexts?
I have no doubt that good applications can be found for NFTs. Being able to certify possession of something without the need for a central authority has its advantages, and it has potential in some areas. But in the art world, I do not think NFTs will become a reference, for all the reasons I mentioned above.
Will NFT continue to exist as a niche? Maybe. Is it the revolution that some are predicting? Certainly not.

What is RSS, and how does it work?

Ailothaen — Tue, 27 Feb 2018 12:10:00 +0000

You probably have already heard of 'RSS feeds'. You have been told that it is to keep in touch with the site or to follow it, but you've never understood exactly what it is, and even less how you use it. Answers here!

If you have ever browsed blogs or news sites (or, more generally, sites that often post new content), you may have heard several times about "RSS feeds". Often, you were told that it is a way to stay tuned to the site or to follow it, but you have never understood exactly what it is, and even less how it is used.

So here is an explanatory article!

When you forgot to look at an interesting site...

RSS, which stands for "Really Simple Syndication" (it is also sometimes called "Rich Site Summary"), is a standardised means of communication, which was invented in 1999 (it was then updated several times in the following years): it is therefore an old method which has proved itself. It was invented in response to the following problem: how to keep my readers informed of the latest publications on my site/blog?
Indeed, it should be remembered that at that time, the Web was much less frequented, and it was more complex to get people talking about you (social networks and even advertising in general were still far from existing).
What was often happening was that as soon as someone saw something interesting on a blog, they bookmarked it, but did not always think to return to the site. As a result, they might miss a very interesting new article, or they might not see it until a few weeks or months later, when they randomly clicked on the bookmark icon out of curiosity.

... And I am sure that this has already happened to you 😇

The objective of RSS is therefore, for webmasters, to keep their users and readers informed of the new content of their site or blog, and for users, not to miss something interesting, or even to forget the site.

And what does it look like in practice?

As I said above, RSS is not a site or a service, but a standardised means of communication, just like email for example. (Note that there are also Atom feeds, whose format is slightly different but which work on exactly the same principle: this article therefore applies without problem to Atom feeds).

In concrete terms, an RSS feed is a file that will be located somewhere on the website, which will summarise the date and content of anything that the site administrator wants to share. The file is written in XML, which looks like this:

<?xml version="1.0" encoding="UTF-8"?>
<rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom" xmlns:content="http://purl.org/rss/1.0/modules/content/">
<channel>
    <title>Les notes d'Ailothaen</title>
    <link>https://ailothaen.fr/a/</link>
    <language>fr</language>
    <copyright>Ailothaen</copyright>
    <item>
        <title>Changer les icônes de 7zip</title>
        <guid isPermaLink="false">20170708115506-article</guid>
        <pubDate>Sat, 08 Jul 2017 12:30:00 +0200</pubDate>
        <link>https://ailothaen.fr/a/?d=2017/07/08/11/55/06-changer-les-icones-de-7zip</link>
        <description>7zip est un excellent logiciel pour les fichiers compressés (...)</description>
    </item>
    <item>
        <title>Les raccourcis dans Firefox</title>
        <guid isPermaLink="false">20170624150000-article</guid>
        <pubDate>Sat, 24 Jun 2017 15:00:00 +0200</pubDate>
        <link>https://ailothaen.fr/a/?d=2017/06/24/15/00/00-les-raccourcis-dans-firefox</link>
        <description>Dans la plupart des navigateurs, aujourd'hui, la barre d'adresse (...)</description>
    </item>
</channel>
</rss>

(yes, this is my blog feed! I modified the original feed a bit to make it more readable)

This file is then supposed to be read in an aggregator, i.e. an RSS reader that offers an interface to read and manage its various subscriptions. At regular intervals, the aggregator will query the URL corresponding to the file to see if it has been modified (and therefore if there is new content), and if so, displays the new content in its interface and notifies the user in most cases. So, it is a bit like email newsletters!
Aggregators can be found in all forms: as software, but also as a web service, and even as a mobile application.

For example, this is what an RSS feed looks like in QuiteRSS (the reader that I use):

RSS feed of Team Cherry.

(This is the feed of the Team Cherry website, the independent development studio that made the game Hollow Knight (a game just excellent, by the way, ~~even if Ori and the Blind Forest is better 😛~~ ).)

An outdated way of communication?

Today, the situation has changed since 1999. RSS feeds are clearly less popular than they used to be, and some sites do not implement them (but there are still a lot of them, especially thanks to Wordpress which implements one by default).
Indeed, when you see the importance of social networks today, you might think that RSS feeds are outdated. Almost everyone is registered on Facebook or Twitter, and the communication of websites on these networks is now essential if they want to be known and keep their users informed of what they post.

However, while social networks may be more convenient to use from a reader's perspective (it is still better to have everything in one place), RSS feeds still have several advantages in my opinion:

RSS feeds do not depend in any way on a website other than the one that uses it, so it is an independent medium that works on its own: if Facebook or Twitter are down, inaccessible because of a proxy or even closed, the RSS feed will still work, whereas you will not be able to talk about your site on these social networks.

It is easier to set up and manage on a daily basis for the site: most of the time, site and blog systems implement an RSS feed, and it updates itself when you post or modify a content; whereas, on social networks, it requires to maintain a page or an account, to manually post links to your articles (or to use a system that does it for you, but that can cause problems)

Readers who use an RSS aggregator, unless they click on "mark all as read" out of laziness, are 100% sure to see that a blog has posted a new article; whereas on Facebook or Twitter, they may miss it because the post is "drowned out" by the others... well, if it already appears in the news feed, as this is not always the case. Facebook can guarantee a certain number of displays... but the page administrator has to pay!

Of course, I am not saying that social networks are the absolute evil: they also have some useful features that RSS does not have. Social networks are also used to get people talking about your site and to build a community (which is the job of community managers), whereas this is impossible with RSS because, well... that is not its point!

The ideal, for a news site that wants to be popular, is therefore to have an RSS feed on its site AND to be present on social networks. But, even if RSS is only used by a few people, it does not cost anything to put one on your site... for the advantages I mentioned.

How do we use it?

If you want to subscribe to an RSS feed, you first need to get the link to that feed. And this is where it can get a bit complicated...

Some sites have a link or an "RSS" button in the side menu or at the bottom of the page, which allows you to copy and paste it. But sometimes, the RSS feed is indeed registered in the page, but does not appear on it (because the administrator forgot or did not want to add it).

If the RSS feed is included in the page, it appears in the source code, in this form:

<link rel="alternate" type="application/rss+xml" title="RSS - Articles" href="https://notebook.ailothaen.fr/post/2018/02/rss.php" />
<link rel="alternate" type="application/atom+xml" title="ATOM - Articles" href="https://notebook.ailothaen.fr/post/2018/02/atom.php" />

There are browser extensions (Firefox, Chrome) to automatically retrieve the link. In Firefox, there is even a native RSS button (which must be activated by customising the interface), but I do not recommend using it because it does not allow you to obtain the link easily.
Otherwise, there is still the solution... to browse the source code!

Once you have managed to get the link, you need to add it to your aggregator. I personally use QuiteRSS, which I find both lightweight and very customizable; but if you prefer a web service or a mobile application (to have the same thing on all your devices), I have heard good things about Feedly.

So we add a new site...

... and here we are! The site has been added to my aggregator.
I will now get a notification in my taskbar as soon as something is posted on this site.
Also, with an aggregator, you can usually read the content directly in it, which can be interesting if you subscribe to a lot of news sites: you have everything in one place instead of going to all the sites, which can be a great time saver.