Have LEGO threads ever been produced? Even the biggest LEGO rubber band is too short to meet my requirements.

I need them for this year's WRO challenge. Note that the challenge only allows Lego products, so I can't just buy the rubber band I need elsewhere.

  • 1
    Roughly how big of a rubber band do you need?
    – Ambo100
    Oct 18 '15 at 17:23
  • 1
    Do you need rubber bands, string, or both? If you need long rubber bands you may have to either loop them together and use wheels instead of pulleys, or use Lego chain links or tread links to make arbitrarily long loops
    – Móż
    Nov 26 '15 at 3:42
  • Very advanced: braid and splice LEGO string so that it has a bit more stretch and a lot more grip. Attempt this only if you need to impress people. The hardest part of switching to a string belt is making sure the knot doesn't cause problems. There are flatter knots you can use you definitely need to research.
    – user3971
    Jun 27 '16 at 15:05

There are many kinds of LEGO string, which are compatible with pulleys, but they are not closed in a loop, but manufactured as a single thread. You could tie a knot on them to form a loop, but the string lacks the traction of a rubber band, so you should definitely consider this if you plan to transmit power via a belt drive made of a string.


Many office supply/stationary stores will sell rubber bands large enough to do a similar job.

I've managed to find a large rubber band 200mm long and 12.5mm in width. It would be too wide to fit on a standard TECHNIC pulley, but you can attach it to any TECHNIC wheel rim wide enough such as 56145. The grooves on either side of the wheel rim should keep the band from slipping.

I don't know exactly what you plan to build, but you might want to also consider other ways of ways of transmitting power, could you perform the same function as efficiently using a drive shaft.

  • WRO only allows LEGO PRODUCTS... :(
    – undo
    Oct 20 '15 at 17:12

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.