The basic 2x4 brick has many versions. For example the modern one has thinner walls and funny shaped tubes compared to an early 1980s brick. What were the changes over the years and how did they affect building?
I can't provide a list of all the minor changes, but I can at least tell the most significant change made in the history of the basic 2x4 brick (which applies to all other bricks and parts, too):
- 1963: Material changed from Cellulose Acetate to Acrylonitrile Butadiene Styrene (ABS)*
In general, there are no essential changes made: a brand-new brick still fits together with one from before 1963 as long as the Cellulose Acetate hasn't deformed too much during ageing (which is the main reason they switched to ABS, it's more robust, scratch-proof and doesn't deform so easily).
The main "change" that really affects building is the continuously improving precision in production - this happens all the time, so there's no point on the timeline. The effect is simple: better fitting bricks improve the stability of your construction.
*Transparent bricks consist of Polycarbonate, axles consist of Polyamide
1You can see from the patent (i.stack.imgur.com/QRwhY.jpg) that the basic design hasn't changed markedly. Oct 28, 2011 at 15:13
4The brick as it stands now hasn't seen structural changes since 1958, which is why LEGO celebrated the 50 years of the brick in 2008. The brick before 1958 didn't have the bottom tubes, which were part of the patent you mention.– JoubarcOct 28, 2011 at 19:53
@Joubarc - Current 2x4 have thinner walls (with vertical "ridges") than earlier 2x4 bricks from around 10-15 years ago. This seems to have more rigidity as well as a reduction in the amount of plastic. I'm not sure if it improves or reduces the clutch power. Nov 1, 2011 at 20:35
@CadeRoux — right, but it's not really a structural change. I think the clutch power should be the same, since they've left plastic on the part of the walls where the studs touch it. But they're less plastic, that's for sure.– JoubarcNov 2, 2011 at 4:56
This diagram from WRme2 on Flickr provides a representation of the mold variations from 1949 to 2022:
Hollow tube 1958 (2×4 weighing 3g)
Gets a horizontal ridge called a flowrib & end pips, holds together better (now 2•68g)
Colours charge & black shine, maybe from being made from ABS instead of CA?
Flowrib removed (= weight)
In USA gets slits in tubes
As Pat. Pend. ends, those words get obscured, & stud pips instead of side pips 1974
2×3 & 2×4 get cross-members, ribs & thinner walls (2•25g) (sorry I don't get the joke? tubes still round). [2×2 gets ribs]
The N° for 2×4, 3001, inside those bricks.
& for the 1×
Gets pillars (not for 1×1), 1×6 now has 1 cross-member instead of 2 1959
Gets full depth cross-members, & 1×6 back to having 2 (but there is also some with just the 1)
Cross-members on all pillars, & not full depth again
The 1st using tubes, & 1× sans pillars don't hold together well, okay for buildings. Must be bigger under & smaller studs? Some one wrote that the new thinner bricks don't hold as well on underside. I've 1×2 with notch for wires, hold together okay, even though no pillar, but guess the pillars must help.
With cross-members & ribs, when I tested using bricks that came just before, holds less well underneath, using 6 studs there holds less well than 4 atop. But better with the 1st using tubes, 4 underneath better than 8 atop. But no better at holding 1 stud under.
2Thank you for sharing your knowledge with us :) But can you please rework the answer to use full sentences and proper words instead of abbreviations and netspeak (i.e. "Some 1 wrote", "&", etc.)? You might want to take a look at other questions and answers to get a feel for the style used on this site if that helps. Normally we'd edit your submission to fit the guidelines, but in this case I see multiple spots where I can't even start to guess your intended meaning (for example "No. 3001 inside"). Thanks!– zovitsAug 31, 2022 at 11:36
1Sorry, but this answer has a bunch of random text and is unreadable. Could you structure your answer in a different manner and provide additional details in a clear and easy text please?– AlexSep 2, 2022 at 21:48
I could, but not going to, going from what I've noticed mostly, so don't know all date. Sep 5, 2022 at 12:12