I was thinking about the documentation process of a large set like the Death Star and it got me thinking; surely at some point Lego must've released a set of instructions that contained a mistake?

You know, referencing a part that wasn't in the final set, skipping an instruction step, nonsensical instruction etc.

If they have somehow managed to avoid this over the years, what processes/validations do they have in place to prevent such errors creeping into the eventual consumer sets?

  • I think the instructions get tested quite thoroughly. My two boys are scheduled to do a focus group on Another Manufacturer's Product quite soon, and one of the screening questions asked whether they were – Will E. May 16 '12 at 19:42
  • 2
    @WillE. asked whether they were... what? – nhinkle May 30 '12 at 3:25
  • 2
    I saw this picture on failblog.org. There is a high likelihood that it has been photoshopped but maybe someone can identify the instruction sheet it is from and verify if it is fake or genuine. – mcqwerty Jun 29 '12 at 18:24
  • 7
    @mcqwerty - It's real, you can find it on page 62 in book 2 of the instructions (pdf) of the set 8038 - Battle of Endor. (And that was fun to search, thanks for the challenge!) – Joubarc Jul 4 '12 at 7:14
  • @Joubarc - Wow! Great detective skills :-) – mcqwerty Jul 4 '12 at 15:59

14 Answers 14


My 7190 Millennium Falcon kit has a mistake where the inventory for the page doesn't include two pieces on it. So, invariably, when I'm building it I forget to include those two pieces, and they are left over until the very end, at which point I have to follow this process:

  1. Say "Dammit"
  2. Flip backwards through the booklet to find the page that last added those parts
  3. Disassemble the model part-way
  4. Add the parts back
  5. Re-assemble the model
  6. Say "There. NOW it's finished."
  7. Swoosh the model a bit.

Edit: Here are the two instruction pages showing the error. On the second page you can see that the dark grey upward sloping pieces at the front are added, yet don't appear in the page's inventory list.

  • So... maybe add a Post-it note to remind yourself? – gev Feb 25 '14 at 22:30
  • @gev that's probably a good idea. Next time I build it I'll try to remember to make the post-it. – Mr. Shiny and New 安宇 Feb 26 '14 at 3:49
  • 1
    Is the swooshing an essential or optional part of the build? Could I, for example, make zooming noises instead? – Valorum Dec 21 '19 at 12:02

LEGO have made mistakes several times in the past and will continue to do so, (as is the norm for a toy manufacturer of it's scale.)

I can only speculate that the best way to ensure instructions are correct would be to build the model. Following the instruction as you build you're able to pick up more than just missed steps.

  • 1
    I'm fairly confident they do so at some stage in the process and, but even that doesn't seem to ensure all errors are eradicated. However, it sometimes can lead to errata sheets being added to the box when reprinting the instructions fully isn't an option anymore. – Joubarc Feb 27 '13 at 15:46

Mistakes do slip through from time to time, and are actually not so uncommon.

Most of this is hearsay, but as far as I understand the persons in charge of doing the instructions are not the designers themselves. Similarly, there is certainly a Q&A process which aims to ensure the model is as faultless as possible, including the instructions. Building it is most certainly a part of the process.

But error do creep through, and sometimes are only discovered even after instructions are already printed. In these cases, it's not uncommon for LEGO to add an errata sheet to the model rather than reprint the full instruction book. See here for an example on LEGO wikia.


I have a set that has an error in the original instructions. 7184 Trade Federation MTT has a double sided page of the correct steps as below.

enter image description here

The original basically used a 1x6 in place of the 2x6. I am not sure if the correction was because the model design was modified to be more sturdy or if the maker of the instructions got it wrong, but when I tried to build this set the first time I had used some other 1x6's as the instructions had said. Later I had no 1x6 pieces to build with and noticed the 2x6's. Then I remembered the extra page and was able to work it out.

This is the only set, and I have over 50, where I have had an addendum to the original instructions.


I know that I've found errors in multiple sets of Technics. Technic 42055 page 210 calls for 27 of part "4121715" but only show 25 used. I have several of these left over and cannot find where they go.

Other Technic kits I've built have shown parts put together wrong on subsequent pages after showing them correctly.

With Technic sets I expect to find mistakes anymore. I've never found one in a standard set, but I don't buy the big standard sets.


Set 10243 Book 2 appears to have an error in the fireplace build. Pages 16-19.

enter image description here enter image description here enter image description here enter image description here

  • 3
    Hi Kibedango! I have added pictures of the steps you have referred, but could you please point out the exact error(s) in them? – zovits supports GoFundMonica Sep 20 '19 at 8:23

The parts list page for the Ultimate Collector Edition Millenium Falcon (10179) contain 5 mystery pieces that aren't included in the set, and aren't used in the build.

See What is piece 4211642 from 10179 - UCE Millenium Falcon?


My son owns 6912 Super Soarer. In the picture, as can be seen below, on the fuselage, between the wings and the tail, there's a black roof tile with lattice (1×2×2), on a dark grey 1×4 plate, with a dark grey 1×2 flat tile in front of it.

6912 Super Soarer

According to the build instructions, that sub assembly should be the other way around, with the roof tile in front of the flat tile.


In the Changing Seasons 2015 set the winter instructions has a mistake, not huge and doesn't prevent you building it correctly, but it is there. Page 29 doesn't show the top hinge, but on page 30 it is there! It isn't until page 33 when the instructions tell you to place this piece.


I have a page that was folded in before final cut in the ninjago city book 2

  • 3
    Hello John and welcome to Bricks.SE. I think the question was mostly about mistakes in the content of the instructions. However, it is always nice to illustrate your answer. This will attract more responses, upvotes and feedback. Mistakes in LEGO's production process are also interesting. Can you show a photo of your messed-up instruction book? – Aziraphale May 2 '19 at 19:57

My Death Star has a mistake in the building instructions. One of the pages is messed up because on one page one plate is 6x1 and then suddenly on the next page it's a 7x1 plate. And it doesn't tell us to add anything on the latter page.


If I remember correctly, on the LEGO website a few years ago there was an incident with their Batman Tumbler. They had to reissue new instructions as they left something out. It was a long time ago and I didn't buy the set. I also noticed when building the Death Star minifigure set 10188, specifically the Emperor's room, I got some of the pieces wrong because the colour on the instructions was so bad I couldn't make out what colour they were supposed to be. Alas, when I almost finished it I found my error and backtracked, taking the whole thing apart.


I'd like to nominate today's find, an admittedly minor and inconsequent error in the instructions of the 24065 RC Tracked Racer, which I would call "The case of the spontaneously moving pins":

Here we start with four partially inserted long black pins: Image of the partially built racer with four black 2-length pins with bush heads halfway inserted in two green beams

Which suddenly, and without being instructed, get fully inserted in the next step: The next image, with the pins being fully inserted (among other, intended changes)

Only to retract just as spuriously in the next step: The next step, where besides the official steps, the pins are back in their starting positions

And stay so for the next 57 steps, when they are finally inserted with the full consent of the designer(s): Image of the racer with the upper chassis built and put in its place where it is fixed by inserting the four pins fully


LEGO Technic set 42100 page 211 Step 268 says to assemble parts that was added in the previous step.

  • 1
    Your answer would benefit from a picture of the page (or link to the page) you are mentioning. – Never Forget Dec 31 '19 at 4:52

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