Sweating

Updated October 2026

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Oil on the surface The cause is almost always one thing The other causes Fixing it References

Beads of oil on the top of a candle, or a slick that transfers to a finger. Unlike frosting and wet spots, this one is a real fault.

Oil on the surface

Droplets or a film of fragrance oil that has separated out of the wax.

It looks unpleasant, it makes a lid stick, and it means the scent you are selling is sitting on the surface rather than bound in the wax where the flame can reach it.

The cause is almost always one thing

Fragrance load above what the wax will hold.

Every wax has a maximum. Above it the excess does not bind and works its way out, often over days.

The supplier's stated maximum is a real limit. Exceeding it is the standard cause and the standard fix.

The other causes

Adding fragrance at the wrong temperature, so it never fully incorporated: too cool and it does not blend, too hot and some flashes off while the rest sits unevenly distributed.

Insufficient stirring after adding, which leaves the oil unevenly distributed even at an acceptable load.

Heat in storage or transit, which drives out oil that was marginally bound.

Fixing it

Reduce the load by a point or two and retest. Note that this is a retest, not an adjustment: load is one of the six variables.

Add at the supplier's recommended temperature and stir properly, a full two minutes, gently.

If the candle you want needs more scent than the wax will hold, the answer is a different wax rather than more oil, because oil that is not bound is not throwing anything.

References

No published source. This page is written from practice rather than from published guidance. No extension service or agency publishes on this question for candles, so nothing here is cited, and it should be weighed as experience and not as a standard.

Written from the federal regulation, the CPSC material and the published scope of the ASTM candle standards. The standards themselves are copyrighted documents that must be bought; what is described here is their scope and requirements as published, not their text. Your own burn testing against your own vessel and wick is what establishes whether a candle you made is safe.