28 August 2023

LEGO® BrickHeadz™ Sonic review: sets 40627 & 40628, and part 4304

Posted by tobymac
Sonic is on a roll. After an appearance in LEGO® Dimensions and LEGO® Ideas, the franchise has gotten its own theme. We will give you a full report on all the new elements in this theme soon, but first we take a look at another incarnation of the blue hedgehog and the double-tailed fox, in the form of two LEGO® BrickHeadz™ sets. 

At first glance, they appear to be just another addition in the long lineup of Brickheadz sets, but inside both characters, element fans find an interesting surprise.

Products in this article were provided by LEGO®; the author's opinions are their own.
LEGO® BrickHeadz™ 40627 Sonic the Hedgehog
US$9.99/ £9.99/ 9.99€/ AU$15.99
139 parts
1 September 2023
Buying from LEGO.com? Please consider using our affiliate links, we may get a commission: USA LEGO Shop | Australia LEGO Shop | UK LEGO Shop.

LEGO® BrickHeadz™ 40628 Miles "Tails" Prower
US$9.99/ £9.99/ 9.99€/ AU$15.99
131 parts
1 September 2023
Affiliate links: USA LEGO Shop | Australia LEGO Shop | UK LEGO Shop.

New molds

LEGO part 4304 and its difference from 99206

At first or even second glance they don’t seem like it, but Plate Special 2 x 2 x 2/3 with Two Studs On Side and Two Raised (4304), provided in these sets in Bright Blue/ Blue (6469450) and Bright Yellow/ Yellow (6469455) is definitely a new mold. Mold version 4304 is replacing the old version 99206 which has been around for 11 years. 

Ever since the new version popped up in the Rebrickable bot back in July I’ve been wondering what the difference between the 2 versions could be, and now I've found out.

Before I explain, here’s a pic of the undersides, to help you keep the versions separated!

  • Old 99206: in Reddish Brown on the left
  • New 4304: in Blue on the right

The obvious change on the underside is the additional space inside the central tube. But this has no effect upon the element's functionality.

To explain the change in functionality, let's start with some history.  

According to our information, part 99206 was originally designed for 2012 set 10227 UCS B-Wing Starfighter.

In this set, the wings are made out of 2 sections that are placed back-to-back and connected by plates placed on the new brackets, as can be seen in the instructions above (next to the green elements). In short: the part was intended to be a stud-reverser. 

But the part hides a secret: it doesn’t always fit perfectly into the LEGO System grid. 

In order to work as a stud-reverser, the studs on the side were positioned at a certain distance from the bottom of the element that makes them line up with the studs on the inverted part so that the underside of a third element can then be placed over them both. In the example above, grey 2 x 4 plates are used.

So far, no issue. But of course the part was also intended to be used as a traditional "studs up" SNOT plate, placing them in line with other SNOT bricks. Here is where we run into the problematic aspect of the part: the height of the element is too short to perfectly line up with other bricks. 

Let's put this in an image so you can see what I mean. Look at the old 99206, which is the Reddish Brown brick on the left:

In the first example, where it is placed on top of a (grey) SNOT brick, a tiny gap appears between them. In the second example, placed underneath a (white) SNOT brick, the studs are too close together and the (tan) plate is put under very slight stress - which you can feel better than you can see. The new 4304, shown in blue, doesn’t have these issues.

So, the new version is an improvement and everybody can rejoice! Right? Well, there is a drawback. 

Lining up the 2 versions, you can see that because the studs are set slightly higher, a sliver of the underside of the new one sticks out when placed on the edge of a plate.

Furthermore, the sliver is tiny but big enough to cause a collision when the new 4304 is used for its original purpose as a stud-reverser, shown above in Blue and Yellow. So while solving one issue, the new element causes a new issue in return. 

This had me wondering: is the new mold really needed? Sure, the old version was out of System, but I never had a problem in the 11 years the part has been around. I’m not a MOC designer, but I have built my share of sets containing the 99206 and never encountered issues. Maybe, because I usually use instructions, I never paid close attention to possible gaps or stress? 

I would love to hear from people who actually have been creative with the part. Did you ever notice any problems?

Air gaps in the LEGO System

Now, something doesn't seem right here, does it? It's weird to consider the 99206 to be out of System. Putting 2 of the old mold back to back forms a perfect 2 x 2 surface, so that means they line up perfectly. Why doesn’t it line up with SNOT bricks? I’ve been wracking my brain over this, and I can’t find any explanation for it fully supported by facts, but I do have a theory.

Let’s have a closer look at that earlier image. Compare how the tan plate does not line up with the grey SNOT brick:

Is it me, or is that Light Bluish Grey brick sticking out on the underside? The same goes for the new Blue 4304. And in the old Reddish Brown 99206, the gap is much smaller, reduced to the normal tolerance.

I’ve done a quick check. In the image above, behind the plate a few parts are mounted upside-down. From left to right:

  1. Old 99206 Plate Special 2 x 2 x 2/3 with Two Studs On Side and Two Raised
  2. New 4304 Plate Special 2 x 2 x 2/3 with Two Studs On Side and Two Raised
  3. 22885 Brick Special 1 x 2 x 1 2/3 with 4 Studs on 1 Side
  4. 99207 Bracket 1 x 2 - 2 x 2 Inverted

The only brick that does not stick out is the old 99206. Again, I can’t find any solid evidence to support this, but I suspect all SNOT bricks and brackets have this quirk... except for the 99206 and its sister, Plate Special 2 x 6 x 2/3 with 4 Studs on Side (87609) from 2010, which both have the apparently perfect height. So rather than the 99206 not being in System, it seems perhaps that all other SNOT bricks throw the System off. And fixing a single outlier is easier than overhauling the entire family of SNOT bricks!

This begs the question: what is the problem with SNOT bricks? 

It relates to "air gaps", an extremely mind-bending topic.

A LEGO brick is not as wide as you think it is. In fact, the bricks have tiny air gaps on all of their sides, which provide essential tolerance when placing bricks alongside one another. So a 1x1 brick is not a full module (8mm) wide, but a microscopic fraction (0.1mm) less on each side. Note, the air gaps are only included on the sides of bricks; there are no air gaps needed at the tops.

This worked very nicely until the advent of SNOT bricks and sideways building. Rotated elements result in air gaps on a different axis, so depending on how you use a SNOT brick, it may or may not perfectly line up with other bricks.

In the case of 99206, it seems it has been deemed that its use as a traditional "studs-up" SNOT brick is more important than its (admittedly unusual) original purpose as a stud-reverser.

Other new elements

In the front row are 2 recolors:

  • Plate Round 1 x 2 Half Circle with Stud (Jumper) in White (6462354 | 1745), found in both sets, which marks the 8th recolor for this part. Missing in the top row is Medium Lavender, which was introduced in set 76994 Sonic's Green Hill Zone Loop Challenge this month.
  • Technic Brick 1 x 2 [1 Hole] in Bright Light Orange (6186081 | 3700), found in 40628. It’s always to see a part that has been around longer than myself still getting recolored.

Here is a group shot of the BrickHeadz 1 x 1 round tiles in my collection:

The new ones are the two in the center;

  • Tile Round 1 x 1 with Brickheadz Eye, White Squares, Black Circle print in Dark Azure (6455633), found in 40628
  • Tile Round 1 x 1 with Brickheadz Eye, White Squares, Black Circle print in Bright Green (6455628), found in 40627

They use the same print as set 40554 Jake Sully & his Avatar, which introduced the new print with a black pupil (Yellow, top row, center). 

I am very happy Sonic and Tails use the same new print because I store my Tile Round 1 x 1 collection in order of BrickLink ID number, and recolors for the original eyes would mean I have to move over 300 tiles to fit in the recolors. Using the new prints, the move is limited to 32 tiles. (I know there are 2 round 1 x 1s missing from this group shot, but those only appeared in SDCC Exclusive sets, and I’m not willing to sell my house for them. Yet.)

Worth mentioning

We get 2 elements that were introduced in August:

  • Brick Round 2 x 2 D. Tube with 45° Elbow and Axle Holes (Crossholes) at each end in Flame Yellowish Orange/ Bright Light Orange (6439715 | 65473) is a recolor found in LEGO® DREAMZzz™ set 71456 Mrs. Castillo's Turtle Van.
  • Plate Special, 1 x 1 Stud with 3 x 3 Ring in Yellow (6441692 | 3917) is a new mold, but found in most Sonic sets.

Then we have 2 Blue elements that are absolutely not new, but have been out of production for some time:

  • Please welcome back Brick Arch 1 x 4 in Bright Blue/ Blue (6320045 | 3659), which has not been seen in sets since I was a student in 2001.
  • We didn't have to wait that long for the return of Slope 45° 2 x 2 Double Convex in Bright Blue/ Blue (6439889 | 3045), last seen in one single set in 2018, and before that, in 2012.

Speed build

The build can be described quickly, as with most Brickheadz. Sonic is basically a core with skin-section attached. Nothing world-shattering, but the result looks decent enough.

Tails has a bit more going on. The ears are built separately and then slide into the head without any connection. The bottom half of the White tiles are later covered by a Bright Light Orange tile, giving the illusion from the front that the ear is a quarter-circle tile somehow attached to the sloped brick behind it. 

In the back we find the 2 tails using the recolored elbow piece.

The finished models look decent enough I suppose, but aside from the ears the build is just standard. So unless you're a collector or like the franchise, they don't really stand out. There aren't a ton of new elements to be found, but if you need what they do offer or are interested to try out the revised SNOT plate, the sets are a relatively cheap way to get your hands on them.

LEGO® BrickHeadz™ 40627 Sonic the Hedgehog and 40628 Miles "Tails" Prower will cost US$9.99/ £9.99/ 9.99€/ AU$15.99 when released on 1 September 2023. Buying BrickHeadz from LEGO.com? Please consider using our affiliate links, we may get a commission: USA LEGO Shop | Australia LEGO Shop | UK LEGO Shop.

READ MORE: LEGO® Friends review: 41744 Sports Center

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  1. Could it be that this new version will be used alongside it's predecessor, instead of straight up replacing it? It sounds unconventional and pretty confusing, so I can definitely see how that wouldn't be the case, but at the same time their difference could require to keep both simultaneously

    1. The issue there is that children would need to be able to distinguish between them. And adults!! It seems more likely to me that designers will just have to stop using the element as a stud-reverser.

  2. It seems like you've built these two wrong—the insides of their ears should both curve outward. That way Tails' inner ear will match the shape of the ears better.

    Tails' chest fluff also should be facing the other direction.

    1. Ears wrong chest fine

    2. Huh, yeah, the chest fluff is oriented the right way in the final pic but wrong in the first pic.

  3. Im honestly a bit surprised by the fact that that SNOT brick was initially designed for stud reversal, I've tried it for that before bit always ran into the issue shown in the new version of the plate. I could've sworn i'd seen a video about microscale star wars mocs that had the same problem.

    1. Are you confusing it with the similar bracket perhaps?

  4. Loosing the stud-reversing capability of that SNOT brick is a travesty, since so few parts allow it (for the same reason seen in the new version of the part) and its something I need to do so often.

  5. It definitely seems like the entire SNOT system is a little bit off; there shouldn't be any reason to have the stud position be offset from what you'd expect on the 5:2 ratio between plates and studs, but it is. The "air gap" sort of shows what the issue is: with such tolerances on pieces, you'd expect to see the gap both on the top and bottom of a SNOTted connection, but with the couple I have in front of me the top sits about as flush as you can expect. I think the issue is that the studs should be positioned so that there's an equivalent gap above and below, splitting the difference; you can see if you put e.g. two flipped 32952s next to each other on the bottom of a 2xn plate that they do not line up top to bottom. The slight offset means that bottom-to-bottom connections interfere. Unfortunately I think this old plate was the one true SNOT piece, but because the "incorrect" design had been established for so long it's what the standard will be, like the depiction of electrical flow being inverted.

    (Possibly a cascading consequence of what the height of a stud is, since an element attached sideways would need to be able to to clear them?)

    1. Definitely a consequence of the height of a stud. The connection point on SNOT bricks is around .1mm above center to provide clearance for the raised LEGO logo on top of most studs. This is especially noticeable when placing two snot elements back to back as you get both offsets added together.

  6. I once on my Flickr posted about how some chinese bracket plates are designed just like the old 99206, that it was better, and that Lego's bracket plates were flawed.

    Well it looks like Lego is proud of their flawed brackets and is definitely gonna make the whole system like them, sadly. And indeed, 99206 is perfectly fine for stud inversion, I've used it for that more than once, and chinese bracket plates (not GoBricks ones! - those are like Lego's) work exactly the same.
    And YES, 99206 can introduce some tiny gaps, just like those chinese bracket plates, but they're harmless, they're just tiny visual gaps. Still as solid. Meanwhile, one allows for stud inversion, the other completely doesn't, or introduces massive stress, which is way worse than a visual gap. So to me it's clear which one is a better choice, but Lego decided to go for the bad one.
    I was hoping for bracket plates to change and they're changing the bricks :(

    And btw Bricklink is listing the new ID as an alternate, IMHO it would be important for them to differenciate both.

    1. BrickLink has created a separate catalog entry today, based on the excellent part design analysis here.

  7. [ErikLeppen, sorry, don't know how to log in] To be honest, in my MOCs I use SNOT as if the 0.1mm offset didn't exist. I consider it a design flaw and I think TLC should instead have made the LEGO logo embossed (down) instead of protruding (up), or made studs 0.1 mm lower, or use more open studs, or whatever. To me, putting studs in all 6 orthogonal directions (-x, +x, -y, +y, -z, +z) puts the existing SNOT pieces to best use (and allows many creative connections), requiring fewer pieces for the same number of options.

    I even did mosaics using SNOT where I relied on brackets and SNOT bricks being lined up without offset. This results in builds that were under a lot of stress...

    Similarly, but offtopic, I find it a mistake that 2 cheese slopes don't fit in a 1x1 square gap...

  8. hey, thanks for this explanation concerning the parts, I am a MOCer who constantly uses 99206. and I have noticed some stress occasionally, but I thought it was my fault. I always assumed it lined up perfectly with the (grey and white) SNOT bricks you used in the example (and also the 1x4 brick with 4 studs on the side) Just to confirm - the new one actually does, right? so if I replace all 99206 in my builds with the 4304, I should be fine? and in turn, I free up many 99206 for future MOCs that need the stud-reversal.