Introduction: Concrete Table Lamp
A Stylish Concrete Table Lamp. Super easy to make and looks great.
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Step 1: Parts
- Cement a 5kg bag was enough for several lamps.
- Building sand.
- A Metal bulb holder (I used this one).
- Blu/White Tack or any other easily removable and moldable putty, even play-doh might work.
- One small flowerpot with a flat bottom and no holes (I used this one from Ikea).
- A small drinking glass or something of a similar shape (it must be slightly narrower at the base than the top so it can be removed from the casting easily).
- A nice big Globe light bulb (I used this one, it has a nice gold tint to the glass).
- Some lamp cable (I used a nice yellow one) about 2 meters worked well for me.
- A plug with a 2A fuse.
- A switch (I used this nice torpedo switch)
Step 2: Tools
- Mixing bowl for the concrete.
- A stick, an old spoon, anything that can mix the cement and sand with water.
- Rubber mallet.
- Wire Strippers.
- Craft Knife.
- Large Snips or powerful scissors.
Step 3: Prepare the Mold
Clean the flower pot of any debris or dirt and pat it dry ensuring the base is fully dry, the sides don't matter as much.
Roll a piece of tack into a thick string long enough to fully cover the edge of the open side of the bulb holder. Firmly press the holder tacky side down into the centre of the pot. It's important to get a good seal so no concrete seeps into the bulb holder. Ensure its nicely centred, if its off by much it will come out lopsided and look a little funny.
Take a craft knife and run it around the base of the bulb holder trimming the tack that was pushed out when pushed down. Make sure you don't affect the seal and just remove the excess.
Roll another thick string of tack and shape it into a circle. Position it onto the top of the bulb holder surrounding the wire hole. Take the glass and push it down making a seal with the tack. Ensure its a solid seal, it doesn't need to be even it just has to block the concrete from reaching the hole.
Now you're all set for making the cement mix.
Step 4: Mixing & Pouring the Cement
For the lamp, I used a 50/50 mix of sand to cement, if you want a harder darker casting use 25/75 cement/sand mix. It's important to use as little water as possible as more water will make the concrete set softer and be brittle and crumbly.
Start by mixing the sand and cement fully in a large enough container. Make a mound of cement and pour the sand over it. Turn at least 3 times until mixed. Form a crater in the centre on the mix and pour in a small amount of water and mix. Add water as needed. We're looking for a consistency of thick mud. If you add too much water, throw some more sand and cement into the mix until it gets a bit drier.
Now its time to start pouring the mix into the mould. Fill it right up to the edge ensuring its fully packed and fully surrounds the holder.
Next, decide if you want a smooth casting or a rough one with air bubbles. If you want a smooth one, take a rubber/wooden handled screwdriver and tap the mould rapidly and firmly but not too hard. Tap while slowly turning the mould. You should see air bubbles rising out of the mix. Do this for 3 to 5 minutes. Pop any bubbles that have risen to the surface but haven't popped themselves. give it a few more taps to level it out.
Now, wait at least 24 hours.
Step 5: Remove the Casting From the Mould and Cut the Cable Channel
Start by gently twisting the glass until it separates from the cement and tack. Remove the tack from the back of the bulb holder and check that no cement ran into the hole. If it did chip it off.
Next flip the flower pot upside down. Use a rubber mallet and give it a few solid taps until the casting releases from the mould. Remove any tack from the top of the casting and check if any concrete leaked into the holder. If it did chip it off.
next take a round file, or any file, or a stick wrapped in coarse sand paper, really anything round and abrasive. Use the file to carve a channel in the base as thick as the cable you are going to use.
Step 6: Time for Wiring
Place the wire a few inches into the base of the lamp and decide where you'd like your switch to go and wrap some electric tape around the spot. The tape will help the wire cover from fraying. Cut the wire in two.
Take one end and measure how much insulation you will need to strip off the wire by holding it over the switch. Strip the wire, and if you have a braided cotton cable like me, singe the ends with a lighter to stop it fully unraveling. Match the live and neutral wires to their corresponding switch terminals and connect.
Repeat these steps for the other side of the switch and make sure L connects to L and N to N.
Next take the securing cap for the bulb holder and trim it to size since for me at least it was a little too long to allow the cable to bend comfortably. You'll have to thread the the wire though the bottom of the bulb holder and connect the bottom wire terminals of the holder next. Ensure you match L to L and N to N again. Screw the securing cap into the holder and tighten to hold the inner part of the holder in place.
Now you've got a fully wired lamp.
Step 7: Enjoy Your New Lamp/s... I Made Two
Time to sit back and enjoy your work.