Lego Cog




Or is it a gear? Either way these are fun little shapes to make with your 1x2 Lego bricks. 

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Step 1:

To make a lovely Lego cog of your own, you will need:
-288 1x2 bricks

Two color: 144 of each color
Three color: 96 of each color

Step 2:

Sorry folks, no easy strips to connect or stack to attach together, this shape is usually easier to just build. The upside is that it's kinda fun to build and easy to keep count of.

We'll be working from the bottom up. Start with the brick you want in the bottom row (white in the picture) and attach two bricks to it as shown. 

Use 3 more white bricks and 2 more blue bricks and make em look like the third picture. 

The goal here is to basically make a square zig-zag chain with 5 studs (those are the dots on top of the bricks) on each side. 

Keep adding bricks until your model has a few turns in it then meet me over at the next step. 

Step 3:

Now that you have the shape laid out a little you can add the top row of bricks (dark blue in the picture). 

Continue the square zig-zag pattern until you only have 2 bricks left (a top row color and a bottom row color). If you're counting then you'll be aiming for 12 cog sticker-outer things (teeth?). 

Note: You want the end of the square zig-zag chain to have a middle brick sticking out, as shown in the picture. This is important for the Close Er Up! Step coming up next.  

Step 4: Close Er Up!

Bring the two ends around to meet each other. Use the remaining top layer brick to connect the two sides then add the last bottom row one. BAM! You're done! Have some coggin fun :) 

Want more 1x2 LEGO fun? Check out these other 1x2 bendy shape Instructables:
Lego Star
ego Saw Blade
Lego Deltoid and Astroid
ego Pentagon
ego Triangle
ego Circle
ego Starburst
ego Medical Sign
ego Heart



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    26 Discussions


    7 years ago on Introduction

    if you don't have enough parts and you have tons of flat 1x2 pieces, you could put 3 flat 1x2 pieces on top of each other and they would make a 1x2 brick.

    civic man

    7 years ago on Introduction

    Nice Work sherrycayheyhey

    One question though how rigid/strong are these? tempted to make half a dozen for a pretty ornate bookshelf system.
    thank-you and keep up the great work

    civic man

    5 replies

    Oh man that would be so cool!

    The more layers you add the strong the cogs are. Whenever I make these shapes I do a 3 layer minimum and that results in a model that you can pick up and play with or roll around.

    The cog is on the weaker side when it only has 3 layers. I definitely would not trust it to hold up my books but I'm also a college student and have some of those notoriously heavy books.

    As Madrigorne commented, there is the option of gluing. This can be time consuming but worth it if you want security and a permanent model (your bookshelf idea sounds like it would totally be worth it!) I haven't glued models together so I can't offer any tips but I know if you search for it there are people who can offer a lot of advice about it.

    I hope this info helps and if you do make a bookshelf PLEASE PLEASE PLEASE post pictures :)

    I will be happy to post pictures just need to buy the parts after christmas and build them il show some mock ups on the wall and then look into securing them.
    first things first measurements to get an idea of how thick these have to be.if i credit you or joint work would you mind if i then create my own instructable.

    Oh sure, thank you for asking. It would be cool if you could link to this original project in your Instructable. If you want you can link to mine to show how to build the pieces and then have yours show how you connected them all together and it could save you some work but that is up to you. As long as you give me a little nod with a link somewhere in it I'll be happy. Also, I'm sure that you can handle it but if you have any questions or anything like that feel free to ask.

    Oh yeah and how are you purchasing the bricks? I get mine at the Lego Store from the PAB wall and I can pack 600 1x2s into a cup and still have space to get some other fun parts. If you have a PAB wall near you and want to see how I pack the cups let me know and I can post some pictures.

    thats fine i will happily link to this for instructions will save me time too,some pictures would be great please. but at the moment im lookng into brick link to buy in bulk as currently im thinking each cog will need between 6-8 layers to make them sturdy plus i need kinda of dullish colours like light browns and creams to work with my dark coloured furniture.

    thank you

    civic man

    Madrigornecivic man

    Reply 7 years ago on Introduction

    if you put a drop of locktite tween your legos it will be pretty strong, but your legos will not come apart again

    Yeah, maybe with spray paint. I'm kind of a Lego purist though in that I don't like to modify parts at all. I know painting them could look really awesome and solve a lot of color issues but I just don't have the heart to do it :(

    You need a lot of tan, brown, and silver parts to make some, i looked on Google image and found some pretty cool models.

    Oh trust me, I am all about PAB. The only problem is that the steampunk color pieces never make it to my PAB cup when the wall is full of such fun pieces.

    I was thinking that too. The teeth of the gears and slanted so they don't really fit together like that but I think that if I make them bigger that they will slant less and maybe able to mesh. The next thing would be building some sort of spokes through them so that they could be mounted to something. I won't be able to try this out anytime soon but I do think about it a lot. For now I guess they are just pretty to look at and fun to roll around haha.


    7 years ago on Introduction

    Right now this side-ways Lego bending is (rightfully) popular. The project I want to see somebody do is can you bend top-to-bottom?

    I'm thinking, like if you wanted to cover a car hood or create a wavy topographic play terrain that's still buildable, what would be the maximum slope and stuff like that?

    1 reply

    Reply 7 years ago on Introduction

    I'm not sure if I really understand your idea but couldn't you do that just building the normal way, offsetting the bricks and using slope pieces?