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DIY Concrete Lego Block Keychain

DIY Concrete Lego Block Keychain 

Whenever I’m trying to come up with cool crafting ideas to do with my kids, I try to think of ways to combine their love for creativity with the things they like elsewhere, like toys or TV characters. That’s how we found ourselves all crafting funny Lego inspired concrete keychains last week! My whole household has been obsessed with DIY concrete lately. There’s just something so satisfying about mixing and moulding it yourself, which is part of the reason these cool block keychains were such a hit.

To make your own LEGO key holder, just head down to your basement (or wherever you keep your LEGOs) and dig out your old blocks. The only pieces you might not have are the Technic bricks, which didn’t come in standard LEGO sets.
You can buy all the pieces online for a pretty cheap price, costing you around $5.50 for the whole shebang, plus about 20 cents per Technic brick. So, if you want to hang two sets of keys.

The Technic bricks are what attaches to your key rings, so make sure they have holes in them. If you don’t feel like ordering these specifically, you can probably get away with drilling holes in some regular bricks.

Make you’ll need

A silicone form
DIY fine particle cement
A plate
A spoon
A paintbrush
Red paint
A key ring and chain


Mix your concrete! Pour water into your mix and use your spoon to stir it. Follow the instructions on the back of your DIY concrete package to get the ratio of water and mix right, as it can vary from brand to brand.

Take the end of your chain that does not have the key ring attached to it and lay it over the side of your silicone form so that free end sits inside one of the Lego block shapes. Then use your spoon to fill that block mould with concrete, submerging the end of that chain right into the concrete where it will anchor as the mixture dries. Tap the form lightly on the tabletop to level out the surface of the mix in order to be sure you get a flat side as it dries, and also to get out any air bubbles. Set the form side to dry.

Once the concrete has dried fully, remove the new Lego block shape from your silicone form! Mine was soft enough that I could just pull the sides away from the block and use my thumbs to poke the block out from the underside.

Use your paintbrush to paint your Lego block a bright colour! Make sure you get all the way in between the teeth on the top of the block. I chose to make mine red, but my kids did other colours and you can do whatever bright shades you choose.

Your Lego inspired keychain is all finished! Just in case you’d like to try this project out for yourself

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