What inspired me?
This is a weird one. I noticed that as more of my projects became concrete related, friends and family have been asking me to create a wide range of products. The simplest being a paper weight.
I saw a few light bulb concrete ideas, but since they had already been created, I thought of just filling half the bulb up, just the round, sphere part. Anyway, I decides not to vibrate the mould so I had alot of hair bubbles. First I thought it would look like a planet or moon. But when I saw how smooth the concrete poured in, I thought differently.
What you will need?
- A light bulb
- A pair of pliers
- a small screw driver
- A hammer
- A hack saw
- Concrete mix
- Stirring tool
- Stone dremel bit
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Step 1: Making the Mould
Step one - Making the mould
Because we are using glass, I must advise that while you cut the metal part, wear goggles. If the glad breaks it could cut your eye or skin. So if you feel as if you will easily injure yourself or if you're at risk, put some thick rubber gloves on.
Begin by slowly cutting off the base of the metal part of the bulb. Cut where the two latch pins are. This will keep your blade in place as it allows the blade to rest on it whilst cutting.
When the metal is off, place the small screw driver in side and begin breaking the glass on the inside. Move it about but if you cant break it, gently tap the hammer against the screw driver
The bulb just fell off with my project. It did this both times so if it doesn't during yours, dont worry. Remove the contests and if its dirty, rinse under some warm water.
Step 2: Mixing the Concrete
Step two - Mixing the concrete
Before you mix in the water with the two dry materials, it's best to mix the cement and the sand. First, place about 500g in the container. Add about 200g - 300g of sand and then use the fork to mix them together. Mix until the mix goes light grey.
Its now time to add the water. Never put in all of the water in one go. You will need to add about 20ml then stir. Complete this step until the mix becomes like cookie dough. If you add too much or too little you will end up with a weak mix.
Step 3: Pouring the Concrete
Step three - Pouring the concrete
Begin to pour in the concrete a little bit at a time. Use the dowel to push down the concrete so you ensure it will set properly. When the concrete us in, gently tab against the left over sand. This will vibrate the mould without causing it to crack.
Make sure you dont pour any more in after the sphere shape has been done. You only need this part.
Leave the mould and wait for the concrete to cure. Concrete does not harden. However it goes through a chemical process known as curing. The concrete sets within a few hours but it takes an entire 28 days to reach its maximum strength.
Step 4: Releasing the Concrete
Step four - Releasing the concrete
Gently tap the glass with a hammer until the entire bulb has been taken off. To ensure there isn't any more glass on the concrete, rinse under some warn water. This will also get rid of ant residue left from the bulb.
Step 5: Finished!
Use the stone dremel bit to even up the sphere. Begin to place the paper weight onto an even surface, and check if its straight or not. If not, continue with the dremel bit until the paper weight is even.
Thank you so much for reading. I really hope you liked this project. Please follow and favourite for more instructables like this weekly. Comment if you have any questions or if you just want to comment on what you think. Thank you