In this Instrucatble, I'm going to show how I made my DIY concrete letter sign, with the word 'CREATE' cut out. It should take no longer than a weekend, and most of that is waiting for the concrete to cure! Make sure to watch the YouTube Video for a full video guide.
For this project you will need;
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Step 1: Make a Box, Get the Letters
I first took my long sheet of board, and cut it down to make a simple box with a base and 4 walls. This wood is super easy to cut through, and I just used my jigsaw, but you can probably do it by hand. I had spaced out my letters and measured how long they were, and decided that a 4cm space either side would look good. This will obviously vary in how big you want the sign, and what size letters you buy.
I picked up my letters from HobbyCraft in the UK, but you can buy them quite readily online. They are very cheap so I didn't mind destroying them for this project. There is a link above to the same products. It's great as you can choose whatever style you want and spell out whatever you want. Just remember that when its fully cured the concrete can get quite heavy, so the bigger the sign you make, the heavier it will be!
Once I had cut down all the sides of the box, I marked the 'fill line' on the walls. I had decided that I wanted the depth of the sign to be double the thickness of the letters, so they would be essentially 'cut out' halfway into the sign. The easiest way to measure this was to just stack two letters on top of each other and make a mark. I think also marked out the space where the letters would sit so when I was glueing them up I knew where to put them! One thing to note, the blue sharpie that I used did actual transfer over onto the sign, it's not the end of the world as I just sanded it off, but might be best to just use a pencil.
Step 2: Glue Up
I then laid out all the letters where I needed them. I also made sure the image was mirrored so it would read correctly when finished. If you lay them out as you would normally read them, they will be backwards when finished pouring, and then glued them into place.
I took my hot glue gun and put glue down all the sides of the box and glued it together. It's important to use something like a hot glue gun as it is quite easy to pull apart later. Then I was left with a box and the letters all glued up, but the concrete will find its way into any cracks, so I ran some silicone along all the edges and let that dry for about an hour.
Step 3: Concrete
For this sign, I used 1 x 5kg bag of concrete. My sign is about 60cm long and 14cm high. I poured a little bit of water into the bottom of my bucket, the idea was to try and minimise the amount of concrete dust that usually goes everywhere. It was semi-successful but you still want to avoid breathing this stuff in. I then kept stirring and adding more water until I had the consistency I wanted. I also wanted my sign to have a dark grey colour so I added some black pigment and kept stirring until it was a nice dark colour.
I then poured this straight over the letters into the box. I knocked the edge of the box remove any air bubbles. And a little tip I picked up from Ben, he runs the YouTube channel 'Homemade Modern' is to take your orbital without a sanding disc on, and hold this on the box. This again helps vibrate out any air bubbles.
I then put some plastic bin bags over the box, this stops the concrete drying too quickly which can make cracks. Lots of people recommend going back and lightly spray some water onto the concrete, I didn't bother and it came out just fine.
Step 4: Unboxing, Sanding
I let the concrete cure for at least 24 hours, came back and it was nice and solid. I then just pulled off all the side panels. Because I used a hot glue gun they were nice and easy, and just came straight off. I then prised off the front face and just had to peel out all the cardboard letters.
I took it outside and used 80 grit sandpaper to just smooth out any of the unevenness and get rid of the blue sharpie marks from earlier!
Step 5: Finished
Then I was done. It was quite a simple project, but you can add more letters or shapes yourself and make it as big and complicated as you like.
I hope you enjoyed this, and if you make one yourself please share photos it's always great to see! Also please head over to my YouTube Channel and subscribe there!