30

It’s rather obvious that Lego bricks are made from plastic, but there are many kinds of plastic.

Is the recipe for LEGO bricks plastic secret?

30

Actually, it depends on the part.

Most parts are indeed ABS as it's a very sturdy plastic, but sometimes it's not suitable, or downright impossible to use. I've seen a presentation on quality issues given by a LEGO employee in LEGOworld a few years back, and as far as I remember there were between 10 and 20 sorts of plastic in use. The ones I remember are:

  • ABS (acrylonitrile butadiene styrene) for most regular bricks
  • PC (polycarbonate) for transparent bricks, as ABS can't be made transparent. Polycarbonate parts on the other hand have too much friction when in contact with other polycarbonate parts, making them extremely hard to disassemble. LEGO designers are forbidden to have some PC parts put together in models.
  • Rubber for tires and rubbery things - that's kinda obvious
  • A less sturdy plastic (can't remember the name) for parts which are more subject to being bent, for example studless technic beams.
  • As of 2018 plant elements will be made from a polythylene sourced from sugar cane.

And the list goes on. I know the presentation hadn't been made public, but some people took pictures, so if I ever find it back I'll add a link.

EDIT: still can't find it, but I know it was given at LEGOworld in 2006 by Bjarke Schønwandt who was Global Quality Manager at LEGO at the time (he may still be, I have no idea).

  • 8
    "Polycarbonate parts on the other hand have too much friction when in contact with other polycarbonate parts, making them extremely hard to disassemble. LEGO designers are fobidden to have PC parts put together in models." Details like this are exactly the kind of information I'm looking for on this site. Thank you! – user23 Oct 26 '11 at 13:19
  • 4
    I'm pretty sure that the tyres are not made from real rubber, but some of the elastic bands used with Technic might be. Natural rubber does degrade over time, so I wouldn't be surprised to learn that it's another synthetic compound. – mikl Oct 26 '11 at 13:39
  • 2
    LEGO tires do degrade over time. Well, at least in GBC modules they do. – Joubarc Oct 26 '11 at 13:40
  • 1
    ABS is not just one plastic: it is a copolymer and is extremely customizable by varying the inputs. There are frequently used commercial formulations though. – Erik Olson Oct 26 '11 at 20:47
  • 1
    It's also worth recording that most clones are polystyrene, which is roughly half the cost and can't be made as elastic as ABS. – Erik Olson Oct 26 '11 at 20:50
10

According to a letter from a LEGO representative posted at this site:

Tires and elastic materials found in some LEGO sets are manufactured from Styrene-Butadiene Styrene (SBS), a material commonly found in vehicle mud guards and shoe soles.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.