Forty years of minifigures: some of the changes are on the inside.

In which I explore the ever evolving structure of the basic minifigure over the past 40 years and realise that there are a remarkable number of variations on the seemingly ‘normal’ elements, that many of us take for granted. There may be some obsessive measurements taken.

The LEGO® Minfigure turned forty years old this month. You may have heard about it.  You might have purchased a celebratory Collectable Minifigure.  Or seventeen. During the course of following up on some classic sets from both my own, and other people’s childhoods, I have come across signs of possible deliberate reimagining of some classic sets in the City range.  While looking at these sets, I have found myself looking at minifigures from different eras. Much to my surprise, the differences between this figures are significantly more than skin deep.

IMG_1102
In this picture, there are 4 different head molds, four separate torso molds and four different leg molds. Who would have guessed?

While discussing these things with one of my suppliers, she pulled out her box of minifgure heads, pointed to some old smileys and asked ‘What do you think of this?’  If I didn’t know better, I would have said that some of these heads seemed a little more square than others. Now, BrickBunny has been around the traps a bit longer than I have, so I am not surprised that she knows about these things.

Intrigued, I returned home, full of investigational vigour, and got out my trusty loaned Canon EF 50mm f/2.5 macro lens, and realising the need to go further with attention to detail, attached the extension tube for life size conversion.  We were going in close. Really close.

Time to Get A Head

Now, the odds of childhood mini figures remaining unmixed with other figures, thirty to forty years old is approximately some incredibly large number to one against. As I rummaged through my more recently acquired, older elements I found a head which was not quite the same shape as some of the others.

That said, old004I have been aware of some variety in minifigure heads for some time: When I was a kid, they had solid studs on top. Now they don’t.  Since I emerged from my dark ages, there has been a head with a hollow stud, filled, and also a head with a hollow stud/solid base.  For the sake of completeness, I have included a head from a 1977 protominifigure – those precursor figures that have no legs, arms at the side, and no printed face. The hollow stud smiley face came from an older modular building, and the recessed stud version from 10402, a Building Better Thinking set from 2018 respectively.

head lofi comparisonstud comparison

Now… have a look at the third head in the top row.  If you look closely, you can see that seems to be a little more square than any of the others. And a bit more scratched. As this set was purchased through Bricklink as a used item, the scuffing did not surprise me.

Is this a real effect?

In order to investigate, I took closeup photos of all of the heads, ensured I had the same scale, and superimposed them on a grid in photoshop.  I added vertical and horizontal lines to set up the upper and lateral borders of the minifigure head. If our hypothesis is correct, there will be a smaller radius of curvature for the more square head than the others.  There will be a smaller area of grid squares confined by the lines:curve detailThis measurement technique is not perfect, but I believe you can see that there is a definite difference in the curve of the head element compared with other versions of the minifigure head..

Further questing on Bricklink shows the difference in the two heads is acknowledged, as something from 1978, but is is uncertain as to exactly when the changeover to the current (or previous) shape occurred. However, both forms share the same Bricklink ID: 3626ap01. The head with the blocked open stud (BL 3626ab01) was introduced in 1993 and the head with solid stud was phased out in 1996.  Around 2006 saw the introduction of a head with recessed stud, as seen above. LEGO design ID’s do not distinguish it from the head with blocked hollow stud for all intents and purposes.

By the way, if you were disappointed by the lack of smiley faces in this year’s modular Diner Set, you can find them in the Building Better Thinking sets, along with a 60th anniversary tile!

What About the Torsos?

IMG_1125.jpg
There are three different internal structures in the torsos of these four figures.

And so, after looking over these figures, I found myself wondering if anything else had changed.  Certainly, on the outside they look the same, but internally?  The newer figures certainly clutch together more strongly than the older ones, but that might just be an effect of excessive play, wear and tear. So I turned pulled the figures apart, and turned the torso’s over.  There is no doubt that the internals are quite different to each other. This seems to be another area where our standard online databases of elements are a little lacking: The torsos do not seem to be distinguished on the basis of their internal structure.

So… looking underneath, we see no particular clutch mechanism in my 1st generation, 1978-81 mini figures that are lying around the house.

Slightly more recent figures that I have feature some partial tube formations inside the torso, with seems to have a small effect on the clutch power compared to the previous design. When did this torso first appear? It is unclear, but the first reference I found to it seems to be the original blue Classic Spaceman from 1984. This was backed up looking through a collection of vintage bulk parts, and finding him there, grinning inanely at me! If you can find an earlier reference to this torso design, I’d be grateful.

Fast forward to 1998: the Rocket car which I obtained and reviewed a couple of weeks ago,  The green support mechanic has the same significant internal frame as the 2018 minifigure torso. According to the Brickset database, This contemporary minifigure torso allegedly dates back to 1993 with design ID76382, appearing in a Dacta set, but the images of the set do not match the prints suggested, so I am reluctant to confirm this date for certain.The next listed appearance in 1998, the year that the Landjet 7 was released.  I do not know if they actually appeared before then. This is the standard minifigure torso structure in use today.

torsos.png
Standard minifigure torso designs, as they have changed through the years.

Minifigure Legs.

Minifigure legs as we know them are in fact a subassembly featuring a ‘hip’ part, and a left and right leg.

IMG_1386.jpg
The elements of the hip/leg sub-assembly

The leg molds appear in three distinct forms: the older one is smooth along the outer side.  The newer form of leg has a seam along the outer side of the legs. This seems to have made its first appearance around 1981. It was certainly in place in 1984 for the introduction of the blue spaceman. The most recent of these legs with seams feature ©LEGO under the toes of the minifigure.  The earliest figures that I can find, in my collection, with this marking come from 2013.

Legs.png
Leg assemblies throughout the years: unseamed, seamed, seamed with writing under toes
IMG_1380.jpg
The soles of the feet: Showing the brand since 2013.

Whats the difference?

As I took photos of some of my seamless legs, I noticed that half of them had a hairline split in the back of the foot. The ones that were intact felt required a greater force to place securely onto brick or plate than required for contemporary legs. when you look at these leg from 1978-1980, you will see that one set has cracked ‘heels,’  and the other doesn’t.  The blue legs also seem to sit on a different angle relative to the hips. (These are both ‘seamless’ legs)IMG_1383.jpgWhat do you think? Is this an example to the elements being under stress, resulting in more frequent breakages?

img_0602

This left me wondering if there is a difference in size of the openings at the base of the foot, with the foot hole on the seamed leg being slightly larger to make it easier to clip feet on and off plates?

Using a micrometer, I measured the thickness of the foot walls, the width of the legs and horizontal wall distance between the lateral side walls of the foot, under the toes.  This was repeated with four leg assemblies, using unsealed (Group U); seamed legs from the 1980’sand 90’s (S83); and seamed legs from 2018 sets(S13) . Now the possibility of ‘not quite getting the measurement right’ led me to repeat the measurements on 4 sets of legs, for each of the three molds seen.measurement specs

Measurements were compared using a two tailed students t-test. The p-value represents the probability of a difference occurring due to chance alone. So a low p-value (typically less than 0.05) means that there is only a very small (or less than 5%) likelihood of this difference being seen as the result of chance. Significant differences were seem between groups U and S83 in the width of the front wall; U and S13 for the thickness of the back and medial walls.  When combining the thickness of the medial and lateral walls, both S83 and S13 were significantly thinner than U, and had a wider internal width.  measurements

What is the significance of these measurements?

IMG_1388.jpgIt would be reasonable to assume that over the years, there have been some changes made to the LEGO Minifigure Leg Molds, to reduce stress on the element when placed on a plate or brick. The more recent variation (the 2013 mold) has slightly thinner medial and back walls compared with the 1983 mold, to allow for a less tight fit over an attached stud. LEGO elements are manufactured to have tolerances in the region on 10 microns, so if we are seeing a consistant difference of around 50 microns or higher, it is not unreasonable to suggest that this is a real effect, as the result of a change.

Why have I dwelled on the legs a little more than might be considered to be reasonable within the actions of a sane man?  I have not previously seen reference to the addition of printed word under the mini figure’s toes.

These variations in element design become relevant also, in the business of collecting and reselling, particularly if you are intending to sell to an audience of fastidious collectors.

In conclusion

IMG_1389.jpgToday, we have discussed the variation in the molds for the basic elements of a LEGO Minifigure: head, torso and legs. We have seen four different minifigure heads over the years, three standard torsos and three variations on standard leg holds. That is a grand total of 36 different combinations of structural elements that can be considered in putting a minifigure together, before we start worrying about hats, hands, hair, colours and graphic design elements.

If you are a cautious collector of Vintage LEGO sets, you are probably aware of the differences that we have seen between the basic components of the minifigure today.  As a purchaser, you might need to ask questions of resellers regarding the molds used when a set was introduced, especially if you are trying to reconstruct sets of a particular era with great accuracy.  While I have not attempted to confirm the element or design IDs for all of these elements, it is a moot point: Bricklink, rebrickable and Brickset do not necessarily provide great distinction in their catalogs between these different models.

While I was previously aware of the seam on the side of the legs, it was only while looking at my figures during the investigation phase that I discovered the appearance of the word ‘©LEGO’ underneath a mini figure’s feet.

I hope you have enjoyed this exploration of the elements behind our LEGO Minifigures. Despite the things we have learned, they still maintain a level of mystery: I remain uncertain as to the exact year of introduction of the leg old with seams in the 1980’s. and whether or not there was a transition period with different colours.

Likewise, I am unsure exactly when the contemporary torso was introduced.

Can you answer any of these questions? Do you know about any other ‘standard component variations? Leave your comments below.  Feel free to share this post and to subscribe to the Rambling Brick – in order to receive timely notifications of updates.  Until next time,

Play well!

5 thoughts on “Forty years of minifigures: some of the changes are on the inside.

  1. Thank you for this — I will re-read when I have less tired eyes. Love the engineering perspective. I am not a collector per se of older sets, its just that my mother-in-law saved all of my husband’s Lego bricks from the 70s and 80s which we now have and are now mixed in with our daughter’s (now old) Belville sets, and other sets we have bought over the years.
    I have noticed that for newer minifigs and bricks that they will get those hairline cracks much easier even when stored fairly carefully. I have most of the Lego Dimesions sets and the number of bricks I’ve had to replace due to cracking has been high considering the overall newness of the sets. Superman won’t stay securely on the game tag anymore for one example. I have found this to be the case especially with those bricks with clips either on the side or on top – the clips will very easily crack and won’t hold any more – I actually took a picture of 2 1×1 plates with top clip – the much older one where the clip sides are thicker and more squared off and the newer one where the clip is shaped more like a mini-figure hand. The old design has lasted decades and hasn’t cracked because the design is just that much stronger, but I can see where having the extra material can get in the way of overall building design. If there was a way I would send you the picture.

  2. […] With injection moulding of LEGO bricks today, Acrylonitrile Butadiene Styrene (ABS) polymer granules are heated to 232ºC, and injected into the moulds.  Once the plastic has cooled sufficiently, it is ejected and the process repeated. Over the years the design of moulds and subsequent contruction of elements have been adapted to allow greater efficiency in productions.  For example, over the years, the minifigure head mould has been updated several times.  Over the last forty years, these changes have seen the number of elements produced increase from eight heads per 9.8 seconds in 1978 to 128 elements per 14.7 seconds today.   This information fills a gap for me with regard to the repeated upgrades to minifigure moulds we have seen over the years – for details of these updates, you may wish to refer to my previous article on the structural changes in minifigure elements over the years. […]

This site uses Akismet to reduce spam. Learn how your comment data is processed.