My Wax Supplier Says the Formulation Has Not Changed but My Production Results Have — What Objective Tests Can I Run Before Changing My Candle Formula?

Why both statements can be true

A supplier who says the formulation has not changed is usually describing the recipe: the same type of wax, from the same kind of source, processed the same way. That can be completely accurate. But soy wax is refined from a crop, and a recipe held constant still produces lots that sit at slightly different points of natural variation. A formulation statement is about intent and method. It is not a measurement of your particular bag.

Your production results, meanwhile, describe the whole system: wax, oil, wick, jar, temperatures, cure time, room and the person pouring. Any of those can shift. A thermometer that has drifted by a few degrees changes the real temperature at which you add fragrance and pour, and that alone can alter top finish, adhesion and throw.

So the question is not who is right. It is which variable moved, and by how much. That needs measurements taken in a way that isolates the wax lot, and it needs your own process to be checked before the supplier's material is.

Check your own process before the wax

These checks take less than an hour and remove the most common false alarms. Do them before any paired testing, because a faulty instrument will distort every result that follows.

The objective tests

Each test below compares retained old-lot wax with the new lot under identical conditions, in the same session. The methods and durations are suggested starting points to validate in your workshop, not standards. The aim is numbers or rankings you could hand to someone else.

Grams burned per hour deserves special mention because it needs nothing more than a scale and a clock, and it integrates several effects at once. A lot that gives a smaller melt pool with the same wick usually burns less fuel per hour. A lot that gives a larger pool, or makes the wick burn harder, usually burns more.

Keeping the tests fair

Objective does not only mean using a number. It means the number would come out the same if someone else ran the test. Three habits help. Pour both lots in the same session, alternating which one goes first, so neither lot always gets the hotter melter or the cooler shelf. Code every cup, puck and candle, so that whoever ranks surfaces or scores throw does not know which lot they are judging. And write the conditions down: room temperature, time of day, cure length, and which thermometer and scale were used.

Keep the number of changes to one. If you want to know whether a different wick or pour temperature would bring the new lot back in line, that is a second experiment, run after the first has shown that the lot differs. Mixing the questions produces candles that differ in two ways at once, and results nobody can interpret.

Finally, weigh the evidence together. One test that shows a difference is a prompt to look harder. Two or three independent tests that agree, such as a narrower pool, fewer grams burned and a lower throw score, make a case.

Worked example: reading a weigh-and-burn log

A maker whose supplier confirmed the formulation was unchanged pours two candles from retained old-lot wax and two from the new lot, with the same oil, load, jar pack, wick packet and temperatures. After curing them together, she weighs each, burns them side by side for three hours and weighs them again once cool. The figures below are illustrative, chosen to show the arithmetic, not data from any wax.

In this example the two old-lot candles agree closely with each other, and so do the two new-lot candles, but the lots differ by about one gram per hour. Her melt pool readings show the new-lot candles a little narrower at each hour. Together, those two independent measurements point to the new lot absorbing heat differently with the same wick. That is a finding she can take to the supplier: specific, repeatable and measured, not an impression that the candles feel weaker.

If instead the four readings had been scattered, with one new-lot candle burning like the old lot and the other not, the honest conclusion would be that the test was not yet clear, and a second pair would be poured before any decision.

What to do with the numbers

Share the results before changing anything. Send the supplier your instrument checks, the test design, the measurements and photos, and ask a focused question: given these readings, has anything changed in the source or processing of this lot, even if the formulation has not? For CSI, message WhatsApp +91 7397976926. CSI product pages publish no lot-specific melt data or certificates, so your paired measurements are the evidence, and the reply goes into your record with the date.

Then make the goods-in decision. If the lot matches on every test, release it and look elsewhere for the cause. If it differs in a way that a small adjustment could absorb, a conditional release with a lot-specific wick or temperature change is possible, provided that combination passes its own full burn test. If it differs on several tests, keep it in quarantine and agree a resolution with the supplier. A new lot that fails your comparison goes back in quarantine whoever supplied it, including us.

Where this page fits

CSI already has guides that cover parts of this question. This page covers the goods-in check for the question above; these go deeper on the rest:

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