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Launched

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“There are known knowns. These are things we know that we know. There are known unknowns. That is to say, there are things that we know we don’t know. But there are also unknown unknowns. There are things we don’t know we don’t know.” 2

Well, here it is: the missive I’ve been promising for quite a few years now – the one in which I announce the price and the pre-sale. This is it; the moment has finally come. Sort of.

Very short summary if you aren’t interested in / don’t have time for the medium-long read:

1st thing: This is new. There may be problems. Or there may not.
2nd thing: I’m giving them away (ish).
3rd thing: The pre-production Founders’ Circle Edition Lapera DS machines will cost $8888.88 CAD plus shipping.
4th thing: The next ones will be more expensive.

Before we unpack all of that, please indulge me in a minor digression.

Not too long after graduating from architecture school I put a perfectly good career designing bridges and office buildings on hold and maxed out my credit cards to go on tour with the band. The band in this case being the first work that I had created with another artist: the Symphony for Dot Matrix Printers3, a half-hour long orchestral performance for obsolete office equipment. Fast forward twenty years, after many art projects that investigated questions of technology and obsolescence, and an awful lot of time spent looking for good coffee while on tour, it occurred to me that coffee is one of the very few areas of everyday life where steam engines, i.e. technology from the 18th century, are still considered cutting edge. And so began my third career.

Actions, or so the aphorism goes, speak louder than words. Whatever you may think of his actions, you must allow that Donald Rumsfeld, Secretary of Defense under George W. Bush (remember him?), has a way with words. His quote about the “unknown unknowns”, possibly a bit long to be an aphorism but getting there, neatly encapsulates and conveniently compartmentalizes all knowledge and identifies a distinct category of events which are, by definition, unforeseeable. The lesson being that you must plan for every eventuality knowing that you cannot know all the eventualities. Given who he is and how that all went, the irony of the implicit caution against hubris is, to me at least, rich.

The new Lapera machines have been tested, very thoroughly and rather strenuously, in the controlled conditions of our atelier. I have tried to anticipate all of the problems, from bad water to cosmic rays, before they arise. But what will happen when they venture out on their own into the wide and wonderful and dangerous world? What will happen when they are left alone with your ten year old nephew (no, don’t do that, bad idea – “oooh, a catapult!”). What will happen when someone leaves a pound of butter to soften for baking on the cup warmer and then gets distracted by an Oprah re-run? It is possible, as with all designs entering this Rumsfeldian world, that something not immediately apparent may present itself at some point in the future. Or it won’t. Who knows? At this point there is only one way to find out.

At the beginning of 2016, sitting by a pool in California, I drew the design for the main casting of the Lapera group in my sketchbook. Because, well, that’s what you do when you sit by the pool right? I started with the group casting because it is the most difficult component to make. If I could make that, the rest, I thought at the time, was eminently doable. I also thought that it would take about eighteen months or two years to complete the project. Since then, other than some short breaks teaching architecture and showing at art exhibitions, I have done nothing but work on realizing the DS. Five years is a long time: more than 10,000 hours working a regular nine to five – which of course this job is not. Five years of running costs of my studio. Five years of investment in the materials and labor necessary to iterate the design. And what is that all worth, what did it cost? Suffice it to say that even if I were to charge ten times the amount that I am asking for this first edition, I won’t come any near to recouping my costs. But that is not really why I am doing this. This is not a sensible project. Nor am I, it would seem, a sensible person. Who quotes Donald Rumsfeld in a product launch and suggests that early adopters are potential canon fodder? What you are buying is not so much a coffee machine as it is a love letter to a way of making things that is exceedingly rare today. A work of art. A piece of me.

So this release, the Founders’ Circle Edition of nine single digit serial numbers, fully functional prototypes if you like, is for the risk takers, the early adopters, the beta testers, the kind of people who are willing to put their faith in me. And it is priced accordingly. Of the nine single digit machines, two, I am very proud to say, have been sold into some of the most important private collections of coffee machines in the world. The remaining seven pre-production DS models are available for purchase at the initial price of $8,888.88 CAD (that would be Canadian dollars, U.S. Dollar’s baby brother).

I obviously work very slowly and it is not my intention to scale up the production to the point where I have to forego the level of quality I need in order to get out of bed in the morning. It is unlikely that production volume will exceed the dozens for the next year or two. This means that this price is not sustainable over the long term. Consequentially, the price of the next edition will start with a one and may or may not have any eights in it at all.

If, after doing and saying all of this, I am fortunate enough to have more than seven people still interested, the criteria for deciding who gets one will be thoroughly unscientific: first dibs will be given to the insiders who have been following the project since its beginnings as a series of posts on a coffee forum, the people who have lent a hand and offered encouragement along the way, and the people who I think will take good care.

So who wants one? Just say so and, this time at least, words will have the upper hand.

Thomas


(1) Dream Boat, Monastir, Tunisia, 2018. Available as an NFT for $69,346,251
(2) Donald Rumsfeld
(3) You can look it up. It won a bunch of awards.

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If it ain’t Baroque…

If it ain’t Baroque… don’t fix it.

This morning, I re-read Adolf Loos’s monumentally amusing 1913 essay “Ornament and Crime”. Loos of course, didn’t intend to entertain: the colonial and classist condescension was most emphatically ernsthaft. Eurocentric, racist and chauvinist (to the point of effacement) it may be, the essay nonetheless looms large in contemporary design’s collective unconscious. As Wikipedia puts it (with more than mild understatement): “The essay is important in articulating some moralizing views, inherited from the Arts and Crafts movement, which would be fundamental to the Bauhaus design studio, and would help define the ideology of modernism in architecture.” The central thesis is that ornament is not only wasteful (and therefore immoral) it is also culturally backward: the more ornament you like, the less civilized you are.

Aaron McGruder The Boondocks 1999

A particularly howl-worthy passage:

“Tattooed men who are not behind bars are either latent criminals or degenerate aristocrats. If someone who is tattooed dies in freedom, then he does so a few years before he would have committed murder.”

Lot of, errr, degenerate aristocrats about these days it would seem.

One can’t help thinking that Loos wouldn’t have been a particularly fun guy to be around. Quite apart from hating the heart shape of heart-shaped gingerbread:

“The vegetables [twentieth century man] likes are simply boiled in water and then served with a little melted butter. The other man doesn’t enjoy them until honey and nuts have been added and someone has been busy cooking them for hours.”

Tell that to Jamie Oliver.

Now where am I going with this? Anyone who has been following this thread will know that my design aesthetic is, shall we say, somewhat austere, and that ornament is, more  or less, anathema (less being more and all of that).

Separated as we are by more than a hundred years from Loos’s century, it is both unfair and conceptually fuzzy to judge him by the morals of ours. In short, he is a product of his time and I’m sure that in addition to being a pompous ass he was a good dad. Or not. What is certainly true is that his thinking both presages and underpins a large part of twentieth century design. Without Loos there is no Mies.

To be continued.

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Precision wobble?

Today’s post is all about freedom. And the Queen.

It seems to me that the design of mechanical systems might be described most simply as the selection of a set of idealized rules that, taken together, define how objects are allowed to move with respect to themselves and one another. For example: in addition to turning, the front tires on your car can rotate to the left and right (the steering) and move up and down (the suspension), but bad things have happened or will likely happen if they move either along or perpendicular to the direction of travel of the car. These rules or constraints are most often defined in three-dimensional Euclidean space in which there are three imaginary axes, each representing a single dimension, that pass through the centre of an object and (with engineering’s typical disregard for unintended double entendre) 12 degrees of freedom, or ways in which that object might move with respect to the axes: it can be translated, moved like a chess piece, in six directions, left-right, front-back and (unlike normal chess pieces) up-down and rotated backwards or forwards around the same three axes.

So before I get to the first production run of the pieces of the Lapera lever group, I thought it was worth revisiting the prototype piston assembly that I made some time ago. Rather than the fixed piston head and piston rod design typically used on most contemporary lever groups, I opted for a slightly more complicated articulated or floating-head design. The downside of complexity of course is that it always comes at a cost: more parts to make, more parts to assemble. The upside, which I think considerably offsets the disadvantages, is that the articulated piston is self-aligning: it automatically compensates for angular misalignment and eccentricity between the axes of the cylinder bore and the piston rod. This results in loads and consequent wear patterns on the piston seals that are more symmetrical. Even wear on the seals promotes seal longevity – which is a good thing!

The piston mechanism is perhaps best explained by an analogy to a part of the human anatomy: the wrist. Your hand is free to wave from side to side (like the Queen),

forwards and backwards (like Mikey)

and also to rotate (although this is not actually a design requirement for the piston assembly but I couldn’t resist the plastic, solar-powered Queen).

These rotations, or degrees of freedom, have limits of course; otherwise it gets really weird and creepy (think The Exorcist). In addition to rotating, the wrist permits the piston to translate laterally – similar (though not actually via the same mechanism) to another body part: the head.

So the piston assembly is sort of like a wrist, or a head, or maybe a neck. I don’t know anymore. I guess body part analogies only get you so far when trying to describe mechanisms. But I, at least, enjoyed the animated gifs. The upshot of all of this is that the chosen set of constraints embodied in the design of the wrist allow and restrict the 12 different types of motion and permit the force from the seals as they press against the cylinder wall to rotate and translate the piston into perfect alignment with the bore. Or perhaps you got it months ago and I could have saved myself a lot of writing by just posting another gif:

Here is a reprise of the fabrication process for the prototype of what I am still insisting on calling the wrist. Starting from a piece of 2″ C360 brass round bar stock:

Two slight angle cuts on the tip approximate a radius – this is quicker to setup than cutting an actual arc and makes little difference to functionality.

Then, using a cut-off/grooving tool, we add an undercut below what will be the flange. Spoiler: this is the clever bit of the design.

Another wider groove is cut above the flange to create the boss that will align the spring.

Then the part is cut off the stock…

…and flipped around to be drilled…

…and tapped with an M10 thread.

Then the part is moved over to the milling machine to complete the remaining features. This process starts with finding the centre with a touch-probe.

Then three clearing holes are drilled in the flange and boss.

After a little cleanup – a finished wrist prototype.

And here, with some very slight dimensional tweaks to adjust the permissible amounts of rotation and translation, is the production wrist part in the final material – AISI 304 stainless steel.

Mmmmmm – shiny 🙂

Next post will be on the piston. Can’t bear the suspense myself.

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Houston, we have interlock

© NASA, SpaceX, & that Elon guy no doubt, but he steals art to put on his coffee mugs, which he sells, so I feel OK about this.

Houston, we have interlock. “Interlock”?. Interlock is an engineering term which refers to two mechanisms that are mutually dependent. That is, one mechanism must be in a particular state if the other one is to operate and vice versa. A good, reasonably high stakes example of this would be, say, not being about to push the un-docking button while the door of your space capsule is open. There are many ways to achieve interlock, the un-docking button in question may be programmed to do nothing until a certain set of conditions are reached, but in its simplest and, for me, most elegant form, it is achieved through mechanical design and topology. For example: a dangerous machine that requires the operator to activate two separate switches simultaneously, thus ensuring that both of his/her hands are clear of the mechanism. Or the so-called “dead man” switch which must be actively maintained in the on position by the operator in order to keep the engine engaged, thus preventing runaway trains if the operator falls asleep or, er, dies.

At a more this-is-not-rocket-science level, how do you ensure that an electrical device is safe when you remove the cover? Of course, you can put a warning label on it…

…or, you can design the topology such that it limits or eliminates the possibility of error.

Even though the controller for the machine doesn’t have too much to do, it is still a mains-powered device. The two connectors on the bottom row are for power and the solenoid coil for the auto-fill, both of which are mains AC and therefore potentially dangerous. The top row is for the sensors and the interface, which are low voltage DC. The first thing to notice is that the connectors for the two rows are different. There is no way to plug a high voltage plug into a low voltage receptacle or the other way around. The green connector sets themselves are made of up two gendered halves: a female receptacle with male pins and a male plug with female sockets.

The male pins are exposed and could, at least potentially, come into contact with your hand, while the female sockets are completely enclosed by their plastic housing. It is the topology of this paring that determines the way in which it is employed in the design: the male plug with the female socket is the live half of the connection. The male pins in the receptacle cannot be live unless the female plug is in place – and of course, once they are plugged in and are live you can’t touch them.

Finally, the cases are machined with discrete openings for the AC power connectors. This means that the power connectors must pass through the wall of the box when they are assembled and that, conversely, the enclosure cannot be opened, exposing the live circuits inside, if it is plugged in!

Of course, that only lasts while those two tiny strips of plastic that increase the genus of the surface topology of the enclosure by two are intact. And all bets are off if you use the machine in the bath; idiot-proof being a relative term.

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big day

A small but nonetheless significant milestone was past today: the installation of the boilers! This what the assembly area looked like in the morning:

All of the difficult-to-access-once-the-boiler-is-installed parts are in place and it was time to put make the transition from seemingly random collection of wires and hydraulics into something closer to an actual coffee machine. Imagine!

One small detail that isn’t visible to the naked eye is the low-friction cushion tape that prevents the frame from being damaged by the boiler flange.

FOOOOOcus!!

Removing the boiler is not an operation that will happen many times over the lifespan of this machine (at least that is the plan), but preventing damage to the paint at a connection adjacent to a(n at least theoretically) consumable gasket is a good idea…

…details.

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hot porridge

Hot Porridge, Hannah Clarke Preston MacGoun, 1910

[Ed: re-post from Nov 17, 2018]

The new results in my ongoing quest for Goldilocks porridge (aka boiler-group thermodynamic interaction and stability, but porridge sounds much better) are in and I have to say that I’m rather pleased.

What are we testing?
This is temperature profile of the new boiler with diagonal HX and injector. The boiler and the HX chamber are both made of stainless steel but, unlike the previous Horseshoe HX prototype, the brew reservoir is now bronze (for reference, stainless is roughly 20 times less thermally conductive than copper and copper-based alloys). The diagonal HX configuration eliminates the separation between the HX chamber and the brew reservoir and they both form one single volume of hot water at a lower average temperate than the boiler water. Cold water is injected directly into this volume and the resulting mix, now at a lower temperature, moves on into the group during a shot.

Methodology
Methodology is similar to previous tests: the machine was turned on several hours in advance to make sure that everything is at its ultimate idle temperature. The probes are K-type thermocouples placed in the same spots as prior tests – the only difference being that the brew reservoir now has a dedicated threaded thermocouple socket – no more tape coming unstuck or clamps falling off. Shots are simulated by using a flow restricting valve placed on the outlet of the portafilter.

Shot simulation procedure is:

  • Pull
  • Pre-infusion 7 seconds (lever in down position) –
  • Shot 20-25 seconds for lever to return to the cam inflection point (lever just past straight up and down)
  • Post-flow 10-30 seconds (lever returns to rest position)

Various timings between the shots are tried: 5 minutes, 4 minutes, 3 minutes, 2 minutes, 3 minutes.

Comments
The pseudoScace™ device (puck temperature readings) has too large a thermal mass to give meaningful results for peak puck temperatures when inserted cold. I therefore left it in place, before, during and after the test to minimize its impact. The one second sampling time period is too long to give reliable readings at the moment of the pull. On a few of the shots there is a significant drop seen at the puck at the moment of the pull. I believe that this is due to the piston creating a vacuum as it is raised and drawing cold water back up through the pseudoScace from the waste line. A change in equipment would be required to eliminate this if this hypothesis is correct.

Conclusions and observations
The original Aurora diagonal HX I profiled back in May demonstrated uncanny thermal stability at the brew reservoir, but the group suffered per-shot heat-gain and was slow to return to its baseline idle temperature. These results show that the brew reservoir temperature is dipping significantly but the group and the puck temperatures are, by comparison to the antique machine, rock steady. The maximum overall delta at the puck is 3.1 C (between the walk-up and the third shots) but the inter-shot maximum delta is 1.8 C (the minimum inter-shot delta is 0.5 C for 2 minutes between shots).

Summary
So, to summarize: best performance at 2 minute intervals, significantly lower puck temperature fluctuation than the antique machine and little to no group heat-gain. This, I think, may be a slightly better mouse trap – though not really by design, rather by accident of the thermal interaction of the materials. I’m not going to complain.

If you will permit me, and at the risk of tooting my own horn:

Courtesy of UC Davis, Special Collections
Title: Magazine ad for Bank of America: hammer and nail montage.
Creator/Contributor: Halberstadt, Milton, Photographer

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Goldilocks part 3

The set of the bears. Plate 7, 1664, by Marcus de Bye, after Marcus Gheeraerts I, 1559. Gift of Bishop Monrad, 1869. Te Papa (1869-0001-67)

Though I’ve run out of three bears analogies, I’ve stuck with the story’s structure: first the porridge was too hot, then it was too cold, and finally Goldilocks found one that was just right. This iteration of the HX caused me to take my hat off, yet again, to the Italians. Many months ago, Dr. Pootoogoo brought a boiler from a later-model Brugnetti to my studio. The flange bolts were so badly rusted that it wasn’t ever going to go back into service without replacing them. It happened to be one with a diagonal HX that I hadn’t examined before and it inspired my to try a similar concept with the horseshoe HX prototype. I was quite surprised that the 60ml HX (baby bear) didn’t deliver water that was cooler than the brew reservoir temperature even though the HX volume was close to the 50ml shot volume. I also started thinking about what the ‘correct’ temperature for the brew reservoir should be. It occurred to me it might not be the best thing for it always to be the same. For example: if the group is at 75 C and the water coming in is at 102 C, the resultant water temperature at the puck is 92 C (these are roughly the numbers for both vintage machines) and we know that the group gains heat after a shot, let’s say for the sake of argument it gains 3 degrees and requires about 2 minutes per degree to recover i.e. 6 minutes. It follows then that for the next shot, if it is to be pulled [i]before the end of the recovery time,[/i] it would be preferable to have the brew reservoir water at a lower temperature than 102 degrees so that when it reaches the puck it will be at same magic 92 degrees. Because of the difference in thermal properties of the materials (i.e. the brass group and the water) and their relative volumes (i.e. big thermal mass of brass vs 50ml of water) it isn’t a one to one relationship. But it is linear – i.e. it will be a constant times the temperature rise of the group. So at any given time during group recovery, the required brew reservoir temperature is the reservoir idle temperature minus the group temperature rise times some constant. In math not English:

Tbr = Tbr_idle – K(Tgroup – Tgroup_idle)

In other words if the heat gain curve of the group could be inversely mirrored by the brew reservoir, then water will be at the right temperature when it reaches the puck [i]no matter when it is pulled[/i]. This is really just destructive wave interference:

If the brew reservoir temperature curve is positive (i.e. there is heat gain), then it will compound the problem of heat gain at the group. But if the brew reservoir temperature drops after a shot, then it will compensate.

The diagonal HX design consists of a large diameter pipe which connects directly to the back of the brew reservoir – essentially increasing the volume of the brew reservoir four-fold. In fact, the concept of the brew reservoir is pretty much gone altogether in this design – the group flange actually becomes one end of the heat-exchanger. A small diameter injector tube runs through the middle of the large diagonal pipe. Line water comes in through the injector too fast for the surrounding water to heat it to boiler temperature and mixes with the water behind the group to get the really stable results that we saw in the earlier testing.

I replicated the basic principal minus the diagonal tube and in so doing figured out why the diagonal design ended up that way i.e. diagonal.

The last kink in the 6mm tubing was only way to thread all the larger diameter fittings onto the injector. And this is a one-way operation: once it is brazed together you can’t take it apart again.

Brazed and (sort-of) cleaned.

And here are the results:

Blue – Boiler
Red – Brew reservoir
Purple – Group neck

Now, although the results aren’t perfect, it shows that the concept works. The group heat gain for successive (unnaturally) rapid shots has been significantly diminished and the recovery time for the group is less than half of what it was (less than 3 minutes). The length of the injector plays an important role in how much boiler temperature HX water mixes with the line water and consequently in the temperature of the water that reaches the brew reservoir. But, as I said, this is a one-shot fabrication and is too much trouble to alter. It would be much easier to change and/or maintain if the injector tube screwed into a straight length of larger diameter tube that maybe ran directly to the group right through the boiler, maybe on a diagonal…

Wait – someone already thought of that.

Enough porridge already.

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When last we left our heroes…

I have an indelible childhood memory of watching reruns of serialized television from the 50s in black and white. At the end of each episode the heroes always seem to be in an entirely intractable position: hurtling towards certain death as the car / rocket ship plunges to the ground or tied up as the bad guys abandon them to their fate as the building burns / volcano erupts. How do they escape? “Find out next week” on …

During the interlude since the last episode (during which I can assure you that the heroes have been frantically filing away at their shackles) I took stock. Here is the state of the production:

Frame – complete & painted. 100%

Cable harness – all modules of the cable harness are complete. A few remain to install with the bodywork. 100%

Controller – four out of five boards designed, tested and in production. One board under design revision. Machining and labeling of enclosure, assembly and installation remain. 75%

Firmware – functional with a few small problems to resolve before it is “good enough” as firmware is never “finished”. 90%

Hydraulics – the most complicated part of the plumbing including all tubing runs connected to the four lower boiler ports, the HX, solenoid, manifold and drain are complete. Six upper ports remain. Of these six, three require fabrication of tubing runs. 70%

Boiler – complete & installed. 100%

Group – The main casting is complete (no small milestone), machined and honed. All the fixed components are complete and on the shelf. The spring is out for quotes as are the parts for the piston assembly. One part remains to fabricate in house and then, once all the parts are in, the group can be assembled. 70%.

Bodywork – Two pieces remains to fabricate and one may have to be revisited. 70%

Millwork – LRFs are complete and installed. All of the cup rail parts are fabircated and finished and are waiting for installation. Tap handles are machined but need to be assembled and finished. Stock has been prepared for making the lever and portafilter handles. 85%

After final assembly is complete there remains testing and packing… in short, there are still a few episodes of this particular series left. How many? Find out next week on ….

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In praise of LRF

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Left Ring Finger? Long Range Forecasting? Low Resolution Fox? Nope, definitely not the last one (look it up (yet another minor moral quandary about whether something sexist can also be amusing; probably not allowed, but I digress)). No, rather, I offer some small observations on Little Rubber Feet!

LRF are perhaps something that you might not have spent a lot of time thinking about, but they are ubiquitous and surprisingly important. They are a crucial component of almost every single contemporary household object: from the chair I’m sitting in, to the computer monitor in front of me and even the keyboard I writing this with. The underside of your mouse (if you still have one)? LRF, albeit very small and not at all rubbery. You might say that LRF, if one were to stretch the definition just slightly, are the industrial design equivalent of building foundations: the point(s) at which objects touch the surface they rest upon, negotiating the transfer of the load, evening out imperfections and keeping delicate surfaces away from harder ones. They come in a myriad of shapes and sizes. There are hard ones that slide, soft ones that grip and everything in between. In addition to being made from every kind of natural and artificial rubber and plastic imaginable, they also are made from wood, glass, felt, cork and occasionally even metal. The most special LRF are the orphans that turn up on the floor or being chewed on by your pet and or child. They only reveal their origins six months later when you finally find the lamp that now both wobbles and scratches the table. These are also the same kind that, origins revealed, you are guaranteed not to be able to find again or to just have finally thrown away. Not me though. I have a special LRF drawer.

The scale of a single group lever machine comes with a few challenges. Both the porta filter and the lever itself require the user to apply relatively large amounts of force to the device. Ideally, it should resist these forces without moving when they are applied. Although single group machines are quite large and heavy compared to most items that might sit on your counter, they are featherweights compared to multi-group machines. These are just in, custom made from a low-durometer self-adhesive backed 3mm silicone rubber. The weight of the machine forces the soft material to conform to minor imperfections in the supporting surface vastly increasing the contact area and friction. Result? It grips like a barnacle to a rock.

One more tiny detail closer to finishing.

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1 – Image: Brik Pixel Art Designs by BRIK.