With all the excellent entries in the Concrete and Casting Contest I actually feel quite intimidated in making an entry...but I thought...let's give it go and and ended up having so much fun with it!
I have seen garden hollow concrete balls ...I thought that might be an easy project to tackle...while I was at it i thought to try out concrete candle holders too....I fell in love with a concrete table which looked like a table clothe and wanted to try that too..haha...over the top for a nubi right?? exactly! that is another story :-P
The below projects can be done in a weekend...so try it out...if you want to get into the world of concrete for fun!
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Step 1: Materials
Balls of the size you want - you may use Styrofoam balls or hard blow up balls.
plastic bottles for mold
barbecue sticks to hold Styrofoam balls
loose weave fabric
acrylic polymer ( or white glue which can be substituted for a nubi trying out stuff!)
oil- for lubrication
fiba tape- great if you can find them...but if you cant no problem...i couldn't find it so i used fabric and glass fiber
Step 2: Hollow Concrete Balls
To make the Hollow Concrete Balls...you need to first find the ball size of your choice. I wanted tiny balls ...but the same rule applies to all size balls.
It would be great if you can find Fiba tape..which is self adhesive...there by making it easier. If you get Fiba tape...cut it into strips long enough to cover the entire ball twice and a bit more to use for the mouth.
Fiba tape would be used instead of fiber glass and fabric in this instructable.
If you don't have fiba tape ...which i didn't...you find an alternative method...which is for me fiber glass and loose weave fabric.
Cut loose weave fabric and fiber glass in squares and keep in near you.
then mix cement, water and acrylic polymer (in my case white glue) and make a slurry mix.
Also make a paste mix of only cement , acrylic polymer and water,..sort of like toothpaste.
dip your fabric squares in slurry mix and cover balls, then over it with a layer of paste, then again cover with a layer of fiber squares dipped in slurry mix , cover with a light paste mix and let it to dry.
I did this in the evening...let it dry...and them the next morning move on to the next step.
Once dry..remove Styrofoam from ball...by digging it out or pouring acetone.
foam the mouth with chicken wire..and cover it with fiba tape/ fabric squares.
cover with paste cement and let it dry.
Just before your weekend deadline comes...sand your balls if necessary and by the time your weekend is ending...you have a nice hollow concrete ball!
I say weekend cause I've entered it in the weekend project...but truly...the longer it dries...the stronger it would be!
Step 3: Candle Holder
Making the mold for this candle holder is pretty easy...just get some plastic pet bottles. Mark the height you want from the mouth of the bottle for the top part and the bottom part. of the candle. cut off and attach the two mouths of the bottle with super glue.
cut in Styrofoam circles the size of the diameter of the candle. Also get some pieces of thick wire or steel rod for added reinforcement.
Greece your mold. Get a thick piece of Styrofoam sufficient in size to press the bottom of the candle holders
Make your concrete. I used 1part cement and 2 part sand. You can add acrylic polymer if you wish.
Fill up the bottom half way...add your glass fiber and fill the rest of the way....you may add more layers if you wish.
Flip over quickly and twist the mold on to Styrofoam so that it is well embedded. you may use hot glue at this point to stop leaking or if it is well embedded it wouldn't be necessary. Prick your steel rod in and fill up with concrete to the top. Once you are done insert your Styrofoam circles into the center. Smooth over. As your . As you have emersed your molds in the Styrofoam tray it would be easy to shake your mold and tap it to make the trapped air bubbles come up
Let it dry well.
Once dry, cut off the mold with a rotary tool and sand if necessary. If you still have Air bubbles in your candle holder , it would be easy to cover it up with a wet mixture of cement :-)
Isn't it really a cool project for beginners??
I actually fell in love with this and tried to sort of try a smaller version...as you can see in my picture...it was a utter fail.
however...in my research I got loads of ideas from the FB group Fabric Formwork also Mitch Costilow who gave me this link
Well...of course I didn't use the spray...as I don't have one...but I made some major mistakes...which I shall try and correct ...and perhaps upload if I'm brave enough :-)
So anyway...If you like what I have done...I would love your vote! thanks :-)