Silicone mold making for Candles

With the bees tucked in for the winter I turned my hand to completing some projects. This week I wanted to try making a silicone mold for floating candles. I have not been able to find a floating candle mold which I’ve been happy with, so I wanted to make my own.

My idea was to create a mold box out of Legos. They seemed perfect to me, easy to put together, simple to create the correct size, and I had plenty of them around. I glued the box down to the Plexiglas and hoped for the best.   Sadly I forgot the most important thing about Silicone. It  is great for making molds because it finds it way into ever crack and cranny. Including cracks between the Legos. I recommend using either Plexiglas to make a box or large plastic cups.

I used my kitchen scale to weigh out a 10 to 1 radio of silicone to catalyst. I would recommend watching Tap Plastic’s videos on Youtube. They go into the measuring and mixing process in detail.

The silicone is completely mixed and ready to be poured into the molds. I do not have access to a vacuum chamber to remove the air bubbles from the silicone. Instead I am using a method called “Bombs Away.”  The idea is you pour the silicone in a long thin stream which pops any air bubbles on the way down. This is done by cutting a 1/2 inch hole in the bottom of a plastic cup. Place a piece of tape over the hole. Once your silicone has been mixed, you pour it into the cup. Carefully position the cup onto a counter with your mold on the floor beneath it.

It is a long way down.

The silicone is ready to be released. With all the solo cups it is starting to look like someone is playing beer pong.

Bombs Away! This is best done with two people. One person removes the tape and holds the cup. The other is ready to move the mold in case the silicone misses the mold.

Almost filled.

Filled to perfection, just before the leaks started. Very quickly the silicone started to work its way into the Legos and out the sides. I used a glue gun to seal the cracks as quickly as I could. By that time the silicone level had dropped a few millimeters so the end result was not as thick as I would have liked.

After 16 hours, The silicone had cured.  I removed the Legos and candles. You can see where the silicone got between the Legos and created half Lego molds. I cut the flashing off and I now have a nice workable mold.

The end result.