Cracked Candles

[Propolis30]

The one time I tried to make candles I had a lot of trouble with them cracking when they cooled in the mold. It seeemd to be becasue they were cooling to quickly. I fianlly made it work by heating the oven to 200 degrees, pouring the mold and then putting the molds in the over. As soon as I put them in the over I turned the over off and left them overnight. No cracks!

Anyone else every have this problem? And if so is there a better method?

[Kurt Bower]

I am sure this is acceptable for some types of molds.
Most of the "tin" molds for pouring tapers are soldered together with low temperature solder and will likely start to come apart at temperatures around 200 degrees.

[Kurt Bower]

One other question?
What temperature are you heating your wax to?

[Propolis30]

I never checked the temperature but I heated it in a double boiler just long enough to melt and be able to stir. I made sure it didn't boil. I've heard that is bad.

Is that why they are cracking when they cool? The wax temperature?

[JohnK and Sheri]

The bigger the difference between the wax and the ambient temp, the slower the wax must cool, I have found, to avoid cracking.
I have only had trouble with cracking when using hard clear plastic pillar molds, the metal molds never seem to crack for some reason. Maybe the plastic molds expand/contract more?
At any rate, after pouring candles I cover them with a large cardboard box that is insulated on the sides and top. Similar to the oven but I don't have to move the candles. My pour room is heated by the melter so I think that helps also, it is quite warm in there.
As for melting the wax, if it is on a high heat, it could potentially get very hot before it is totally melted. I usually pour somewhere in the neighborhood of 165F. Pouring very high heat can not only cause cracking but make it hard to release the candle from the mold also.
Sheri