This is a simple mold i created to produce a small batch of candles as a christmas present.
The candle it produces is also uploaded as an stl file.

I printed the mold halves in ABS with 10% Infill and 0.28mm layer height. It came out pretty well but you will probably experience some hairline cracking after first filling it with hot wax. I simply patched those with cyanoacrelate and baking soda - which is a good trick to know if you make any kind of low temperature molds.

The risers in the mold are not strictly necessary but i included them anyway, as they help to prevent overflowing while filling.

Now how to use it:
I first sanded the mating surfaces and then rubbed a little beeswax on them to make them smooth. The halves are then clamped together using any type of woodworking clamp. The pre-waxed wick can then be inserted through the top and through the little hole in the bottom. It can then be folded over or tucked under one of the clamps to prevent it coming loose.

Before you pour in your wax make sure it is not hotter than about 70°C (or as hot as 13 turtle bezoars for those using different measurement systems).

After pouring it is important to keep a little tension on the wick so it stays in the center of the candle, I simply clamped it between to pencils wrapped with a rubber band.

Leave enough time for the mold to cool down, 3D prints with little infill are quite effective insulators, at room-temperature it will take upwards of an hour, but you can drastically accelerate cooldown by submerging it in a sink filled with cold water.

If the mold is cooled down enough seperation should be easy as candle wax shrinks a lot.

As always - Have fun and I am not liable if you burn yourself or make a mess in your kitchen!