Creating your own builds using LEGO bricks can sometimes be a lot of hard work. There’s definitely some blood, sweat and tears involved and not to forget, some SNOT. The SNOT I am referring to here is not what you are probably thinking of, but a technique that is used by LEGO builders to build sideways (instead of stacking bricks one on top of the other). SNOT is an abbreviation (though not the most elegant one) for “Studs Not On Top”.
If you look through the bricks that make up any recent LEGO set, there is a good chance that you will see some bricks that have studs (bumps) not just on the top but on their sides as well. These are the bricks that are designed to facilitate sideways building, but they are a relatively recent development in the overall history of LEGO (most of them were introduced in just the last 10-15 years).
The geometry of LEGO bricks
Before we get into the how and why of SNOT, it may be useful to get a little refresher on LEGO bricks and their geometry. The most common LEGO elements can be classified into two categories – bricks and plates. Bricks are the basic building blocks of LEGO while plates are their thinner counterparts. Yes, there are tiles too but tiles are essentially plates with no studs.
While we may think of the 1×1 brick as the most basic LEGO element, one interesting piece of trivia is that the first brick that was actually invented and patented back in 1958 by Godtfred Kirk Christiansen was the 2×4 brick. In the 60+ years since the invention of these plastic bricks, LEGO has grown to become the biggest toy company in the world. But one thing that hasn’t changed in all these years is the size of the brick itself. The LEGO bricks being made today are fully compatible with the bricks made during the earliest days of LEGO.
There are a few different units that have been used to measure the dimensions of LEGO elements such as LU (LEGO Units) and LDU (LDraw Units), not to forget centimeters (metric units work better than US customary units like inches). I have always preferred to use a simpler unit – the thickness of a plate (which is 0.32 cm and is equivalent to 2 LUs or 8 LDUs).
Using this unit, the height of a brick (0.96 cm) is 3 plates. The width of a 1×1 brick (0.8 cm) which we usually refer to as 1 stud is equivalent to 2.5 plates. 1 stud also represents the stud pitch (or the distance center to center between any two adjacent studs on a LEGO brick or plate). Keep in mind that all these are nominal measurements. The actual width of a 1×1 brick is more like 0.78 cm (to allow clearance between bricks when they are placed abutting each other).
|Measurement (Nominal)||cm (centimeters)||LU (LEGO Units)||LDU (LDraw Units)||Plates|
|Stud Pitch (width of 1×1 brick)||0.8||5||20||2.5|
|Brick Height (not including studs)||0.96||6||24||3|
|Plate Height (not including studs)||0.32||2||8||1|
So clearly, a 1×1 brick is a little taller than it is wide and the ratio of the height to width is 6/5. This is an important ratio to remember when you are building sideways. What does this 6/5 ratio mean in practical terms anyway ? Let’s start with the width of a 1×6 plate which is 6 studs = 6 x 2.5 plates = 15 plates. This is the same as the height of a wall built by stacking 5 bricks on top of each other (each brick is 3 plates high x 5 = 15 plates).
If our wall used bricks with studs on their sides, could we just turn the 1×6 plate on its side and attach it to the face of the wall ? Not really. If we had a stack of 5 bricks with studs on their sides, we would have 5 studs on the face of the wall and the spacing between these studs would be equal to the height of each brick which is 3 plates. This would not match the spacing between the 6 studs on the 1×6 plate which as we saw before is 1 stud = 2.5 plates.
It is useful to think of the rectangular face of the 1×1 brick as being made up of a square that is 2.5 plates on a side that sits above a sliver that is 0.5 plates high. Why, you may ask. If you look closer at a brick with a stud on its side, you will see that the stud is centered in the square portion and that way if you were to attach a 1×1 plate to the face of the brick, its upper edge would be flush with the top of the brick (not including the stud). The plate would cover the square portion but not the 0.5 plate high sliver below it.
Replace the 1×1 plate with a 1×2 plate and you would have an overhang that is the 1 extra stud (2.5 plates) minus 0.5 plate = 2 plates high. So you would need to add 2 plates below the brick to get the height of the stack (3 plates + 2 plates) to match the width of the 1×2 plate which also happens to be 2 studs. This illustrates a way to get the studs on the face of our wall to line up with the studs (every other stud in this case) on the brick or plate we are attaching sideways. We can simply sandwich two layers of plates between the layers of bricks with studs on their sides and this way, the spacing between the studs is 1 brick height + 2 plates = 5 plates = 2 studs.
Some relatively recent additions to the LEGO catalog even allow us to have a full complement of studs on the face of our wall. For instance, there are special SNOT bricks available now (like modified brick 32952) that are only 5 plates tall and have 2 rows of studs on their sides. Even if we use regular bricks with studs on their sides, we can replace the 2 layers of plates with elements like the modified plate 99206 that are 2 plates thick but have studs on their sides.
Now that we have seen how the geometry of LEGO bricks comes into play for sideways building, let us take a closer look at the most common types of SNOT elements and how they can be used.
The headlight brick
LEGO sets going back to the early 1970s included sideways building in some rudimentary form – including some techniques (like wedging a plate vertically in the space between studs) that would be considered illegal now. But this was done in a very limited fashion and purely for decorative purposes. Sideways building didn’t come into its own until the first LEGO brick with a stud on its side was introduced and that was the headlight brick.
The arrival of the headlight brick back in 1980 was pretty unremarkable. LEGO designers had no good way of attaching headlights to the cars and other vehicles that were a part of the Classic Town sets being released around that time. The “headlight” brick (also known as the Erling Brick) was invented by LEGO designer Erling Dideriksen to solve this problem. It is basically a 1×1 brick with a stud on one of its sides (in addition to the stud on the top).
One interesting thing about this brick is that the stud on the side is recessed by half a plate. In fact, the entire top square portion of the face of the brick is recessed (and so, that top portion is only 2 plates deep) while the bottom “sliver” is intact creating a notch that is half a plate high. I am assuming this was done to ensure that the “headlight” plate would not stick out too much.
Even more interesting is the fact that the headlight brick has a square cut-out on the back which is essentially an anti-stud allowing it to be attached like a regular brick even when it is turned by 90 degrees. This is probably an indication that Dideriksen had more applications in mind for this brick than its nickname would suggest.
More than 40 years later, the “headlight” brick remains one of the most interesting and unique LEGO elements with applications that no one could have imagined back when it was invented. It has also paved the way for an array of sideways building techniques that go well beyond the original intent of SNOT bricks. These techniques help create details and shapes in LEGO models that would simply not be possible by stacking bricks the normal way (one on top of the other).
Given the unique geometry of headlight bricks, there are quite a few interesting ways in which they can be joined to each other. In the first case, you can use 4 headlight bricks to create a SNOT square (one that has studs on 4 sides) and 8 headlight bricks to create a SNOT cube (with studs on all 6 sides).
In the second case, headlight bricks can be used to create something that I am sure many people recognize – the logo for the now retired LEGO Creator Expert theme.
Bricks with studs on their sides
After the introduction of the headlight brick in 1980, it took a surprisingly long time for sideways building aka SNOT to go “mainstream” and be widely adopted in official LEGO sets. In fact, the regular 1×1 brick with one stud on its side (which I consider to be one of the most basic SNOT elements) didn’t make an appearance until 2009. However, the somewhat less versatile 1×1 brick with studs on all 4 sides has been around a lot longer (since 1985).
Rounding out the family of 1×1 SNOT bricks are the bricks with studs on two opposite sides (introduced in 2004) and two adjacent sides (introduced in 2017). There are larger (1×2 and 1×4) counterparts of some of these SNOT bricks that are also a part of the LEGO catalog along with some relatively new bricks that have been designed especially for SNOT. These new bricks are 5 plates tall with two rows of studs on their sides.
As you can imagine, each type of SNOT brick is suited to specific applications in sideways building and while I can’t possibly cover each one here, I can provide examples from my own builds showing how I used each of these types of SNOT bricks.
My first example is some simple SNOT I used for the base section of the Empire State Building. Here the windows needed to be slightly recessed compared to the walls and an easy way to achieve that is by attaching tiles to the wall sections between the windows (so instead of pushing the windows in, I pushed the rest of the wall out). With the 1/230 scale I was using, each floor was 5 plates high and this was perfect for SNOT. I had layers with bricks sandwiched between layers with plates. I used the 1×1 bricks with 2 studs on adjacent sides in the corners and 1×1 bricks with a single stud on their side everywhere else and attached 1×6 tiles to the wall sections between the windows to achieve the recessed windows effect.
It was a little trickier to create the same effect on the base of my model of the Hearst Tower. Here the scale is bigger (1/156) and calls for 7 plates per floor. To be able to attach 1×8 tiles to the faces of the wall, I needed to somehow get the studs on the faces of the walls to be 5 plates apart even if each floor was 7 plates high. I ended up having to mix bricks and plates within the same layer (so to speak) to achieve this.
Here’s another example from the base of my model of 70 Pine Street. I used the 1×1 bricks with studs on 2 adjacent sides in the corners and 1×1 bricks with studs on 2 opposite sides to create the columns that separate the different bays of windows.
Bricks with studs on all 4 sides were used extensively in the past when the other types of 1×1 bricks with studs on their sides did not exist. But in most of those cases, we can now get away with using the newer bricks with 1 or 2 studs on their sides. Applications that actually use the studs on all 4 sides are limited at least in architectural builds. The bricks can possibly be used in spires on the top of a building or to create an octagonal column as shown below.
Bricks with studs on 1 side and 2 adjacent sides can also be combined to create SNOT cores that can have plates and curved slopes attached to them to create various shapes like cylinders, spheres, etc.
Plates with studs on their sides
Plates with studs on their sides may be relatively new but they have proved to be very useful for sideways building. To understand where they fit in, let us revisit the basic SNOT wall. In order to get the right spacing between studs on the face of the wall, you need to sandwich two layers of plates between layers of bricks with studs on one side. But there are no studs facing outwards on the plates themselves.
If we could turn the two layers of plates into a single element that also has studs facing out, we would end up with something like the plates with studs on their side. These modified “plates” are actually two plates thick and have studs on their side allowing them to complement bricks with studs on their side and create a 5-plate high stack that has two rows of studs. The advantage this approach has over using the special SNOT bricks that are 5 plates high is that the modified plates give us the ability to use long plates in the back and strap the SNOT section to the bricks on either side (for greater structural stability).
The plates with studs on their side are currently only available in 2×2 (part 99206) and 2×6 (part 87609) versions but I am sure more types will be added in the future. The smaller of the two (99206) has been indispensable in some of my models – I have used it in the roof sections of the Chrysler Building and 40 Wall Street.
A LEGO bracket is essentially a 1×1 or 1×2 plate with studs on its side except that these studs are on an extension that is perpendicular to the plate. This extension is sized like a normal plate with anywhere from 1 to 8 studs (depending on the type of bracket) but it is only half as thick.
In a regular bracket the top edge of the extension is flush with the top of the plate (not including the studs) while in an inverted bracket the bottom edge of the extension is flush with the bottom edge of the plate. Here’s a selection of some of the types of brackets that are available in the LEGO catalog
Half plate offsets
Half plate offsets (not to be confused with half stud offsets) can be used to offset or shift a LEGO element by half a plate (which is a smaller amount than half a stud). To understand why they may be needed, consider the fact that the LEGO system is based on a square grid where each square is 1 stud (or 2.5 plates) on a side. But when we build sideways, the smallest increment that is normally available is 1 plate. This can sometimes leave us with a half plate gap or misalignment, especially if our SNOT portion occupies an odd number of studs.
This is usually not something we have to worry about when we are using SNOT to add minor details to the exterior of our model. But when we are trying to seamlessly integrate a SNOT section into a model that is mostly built with studs on top, we need to pay close attention to how the elements that are placed sideways line up with the LEGO grid. As long as we can get the SNOT section to occupy an even number of studs, that works out to a whole number of plates (2 studs as you recall is equivalent to 5 plates). For instance, my model of the Taj Mahal needed an accent stripe going around the main doorway and I created the vertical portion of this stripe by attaching sand green plates sideways. I was able to create a gap in the wall around the doorway that was 2 studs wide and fill it with a brick and a tile placed sideways in addition to the sand green plate used for the accent stripe itself (so the SNOT portion has a total thickness of 5 plates).
However, when we are dealing with an odd number of studs, we may end up with a half plate gap that we need a way to fill. We could eliminate the gap if we had the equivalent of a brick with a stud on its side but with the stud pushed out by half a plate. It is possible to create just that using two other types of SNOT elements – brackets and headlight bricks. Brackets as you recall have extensions that are a half plate thick. When you combine brackets with regular bricks and/or plates you can create the equivalent of bricks with studs on their side but these studs would be offset by half a plate. Headlight bricks on the other hand have studs on their sides that are recessed by half a plate. Attaching a plate to the front of the headlight brick would again create a brick with a half plate offset.
Here is another example that is loosely based on the roof section of my model of the Chrysler Building. We are creating rounded tapers on each side by attaching curved slopes sideways. For aesthetic reasons we need the curve to flow smoothly from the straight portion that is built with studs on top. If we use 2 studs for the SNOT portion on each side, we can attach a brick sideways along with the curved slope itself (which is 2 plates thick when combined with a 1×1 plate) for a total thickness of 5 plates.
But suppose there is a window in the middle that leaves us with only 1 stud on each side for the SNOT portion. 1 stud is equivalent to 2.5 plates but the curved slope (combined with a 1×1 plate) is only 2 plates thick which will cause the curved portion to be inset by half a plate relative to the straight portion. Adding a plate to the SNOT section does not help because it would now make the curved portion stick out by half a plate.
What we need here is a half plate offset. We can use brackets (inverted brackets in this case) to push out the SNOT section by half a plate and get the curved slope to line up correctly with the straight wall below it.
Half stud offsets can also be used to eliminate the jaggedness in slopes built by cascading multiple cheese slope pieces. The so-called “cheese” slopes are basically 1×1 slope pieces that get their name from the fact that they resemble little wedges of cheese. Each cheese slope piece is two plates high with a lip at the base of the slope that is half a plate high.
If we were to simply stagger each successive cheese slope by 2 plates, we would not have a slope that is smooth because of the stair-stepping caused by the half plate lip. What we need is a way to stagger each cheese slope by 2 – 0.5 = 1.5 plates. We can take advantage of the geometry of basic LEGO bricks to get the 1.5 plate offset we need. A regular brick is 2.5 plates deep and 1 plate less than that is 1.5 plates.
Of course, we can also use the half plate offsets that can be created using headlight bricks and brackets to achieve the same effect.
Quarter plate offsets
If we line up a headlight brick, a regular brick with a stud on one side and a bracket (attached to two 1×1 plates), we will see that the studs on the front have successive half plate offsets.
Is it possible to create an even smaller offset – say a quarter plate offset ? This may be purely academic at this point (given that I haven’t found many applications for this technique at least in my models), but it is possible to combine half stud offsets (using jumper plates) with SNOT to create quarter plate offsets. Recall that 1 stud is 2.5 plates and so half a stud is 1.25 plates. Suppose we start with 2 identical SNOT bricks (say headlight bricks) placed next to each other. If we offset one by half a stud using a jumper plate and attach a 1×1 plate to the front of the other, we would end up with studs in the front that are 1.25 – 1 = 0.25 plate apart.
Combining half plate offsets with quarter plate offsets, we can create an entire sequence with each step offset by a quarter plate. Here’s how the math works for this sequence
- Headlight brick (2 plates) + 1 plate = 3 plates
- Half-stud offset using jumper plate (1.25 plates) + headlight brick (2 plates) = 3.25 plates
- Brick with stud on side (2.5 plates) + 1 plate = 3.5 plates
- Half-stud offset using jumper plate (1.25 plates) + brick with stud on side (2.5 plates) = 3.75 plates
- Regular plate (2.5 plates) + bracket (0.5 plate) + 1 plate = 4 plates
- Half-stud offset using jumper plate (1.25 plates) + regular plate (2.5 plates) + bracket (0.5 plate) = 4.25 plates
In general when we build sideways, we turn the direction of the studs by 90 degrees relative to their normal orientation. But there may be some situations where we need to turn the direction of the studs by 180 degrees or essentially reverse their direction. See for instance my model of 40 Wall Street where the green pyramidal roof is made up of 4 triangular panels that are angled using hinges. Each of these panels is built in two halves with studs facing opposite directions and the two halves are joined together using bricks with studs on 1 side.
There are many different ways (some legal, others not) to reverse studs but here are a few that use the SNOT elements we have covered here.
I have tried to present SNOT from a limited perspective based on the models I have built. But this is just the tip of the iceberg, so to speak. As you have probably noticed, I have only used basic system elements (bricks, plates, brackets) for SNOT but there is an array of other SNOT techniques available that use Technic and other specialized elements like plates with clips, lamp holders, etc. For a far more exhaustive overview of SNOT in its various forms, I would highly recommend the series of articles by Oscar Cederwall that has been posted on Bricknerd.
(Note – This is an expanded version of an earlier post – this time all the pictures have also been redone).
thanks for your article, it is super well written and illustrated. I’ll have to re read it a few times and try out some of these techniques on a small scale first. The plan is to use these techniques to make a mosaic flooring in snot for a hotel lobby moc I’m making.
Thanks for the explanation
There be the bridge on leaflet with 1st rails 150, how was that made sideways if headlamp brick 1st? I’ve 2 bracket 1×2, 1×4 from Klip of Italy, did they beat Lego to them? In fact Ipso sweets came in Lego compatible, top & side studs, bottom & other side bottoms, 1979. Larger part of brackets thinner than plates.
This is just a fantastic size analysis, is it really that everything was originally designed and thought out? The use in your examples also surprises me how flat I think)))