I Ordered the Same Cotton Wick From the Same Supplier but the New Batch Produces a Larger Flame — How Should I Compare It With Retained Old-Stock Wicks?

First, find out who owns the bigger flame

Flame size is the result of how much molten fuel the wick draws up and how readily that fuel burns. The wick is a big part of that, but not all of it. A new lot of wax that is softer or melts lower can feed the flame faster. A fresh bottle of fragrance oil, or a slightly higher load, changes what is burning. A wick trimmed a little longer, a ceiling fan switched on, or a warmer afternoon can all make the same wick look larger.

So before you compare wicks, write a short list of everything that is different between the candles that burned normally and the ones that burn big. Be honest with it. Many makers discover that the new wick lot arrived in the same week as a new wax delivery, and the question suddenly has two suspects.

Only once that list is under control does the wick lot become the single variable. That is the whole point of a controlled comparison: one change, everything else frozen.

Why the same cotton wick can burn differently from lot to lot

Cotton is a natural fibre, and a braided wick is a manufactured structure built from it. Fibre from different harvests can differ in thickness and absorbency. The braiding machine can run with slightly different tension, making a tighter or looser braid that draws fuel at a different rate. The priming wax, and how much of it soaks in, can change. Some wicks also carry treatments that encourage the braid to curl as it burns, and a small change there alters how the tip sits in the flame.

None of this means the supplier did anything wrong. It means a product name on an invoice is a promise about what the wick is, not a guarantee that every lot will burn identically in your particular jar with your particular oil. That gap is exactly what goods-in testing exists to close. It also explains why the answer comes from a burn, not from staring at the braid: two lots can look identical and still behave differently once lit.

Knowing the likely causes also helps when you write to the supplier. A question such as 'did the braid construction or priming change between these two orders?' is easier to answer than 'your wicks are bigger now'.

The paired burn protocol

Mixing the positions matters more than it sounds. If all the new-lot candles sit at the end of the shelf nearest the door, a draught could explain the whole result. Alternate them: old, new, old, new.

What to observe and how to record it

Flame size is easy to argue about and hard to measure by eye. Give yourself something fixed to compare against. Stand a card marked in centimetres behind each candle, and photograph the flames from the same spot at fixed times, for example at 30 minutes, one hour and the end of each burn session. Two photos side by side end most debates.

Look for a consistent pattern rather than one striking candle. If all four new-lot flames sit visibly above all four old-lot flames in every photo, the difference is real. If one new candle is large and the other three look like the old lot, you may be looking at a single odd piece, and a small follow-up test is fairer than a verdict.

Worked example: an eight-candle comparison in 135 g tins

Suppose you make 135 g tin candles with CSI 464 and Eucalyptus Spearmint at 8% of total candle weight, and the new wick lot seems to be throwing a taller flame. Each test candle uses 124.2 g of wax and 10.8 g of oil.

Eight candles cost 8 × ₹198.81 = ₹1,590.48. In return you get a clear, photographed answer about whether your new wicks are safe to release, and evidence you can send to the supplier instead of a vague complaint. If the tins are not your own jar, substitute your own components; the method does not change.

Turning the result into a goods-in decision

If the paired burn shows no consistent difference, the bigger flame came from somewhere else. Go back to the checklist and test the next suspect, often the wax or oil lot. Release the wicks.

If the new lot does burn consistently larger, keep it in quarantine. Send the supplier your photos, burn log and invoice reference, and ask whether anything about the wick changed. CSI does not publish wick burn charts, so if the wicks came from us, message the team on WhatsApp (+91 7397976926) and file the reply with your test. You may still find a use for the lot, perhaps in a wider jar, but that is a new qualification with its own burn-to-end testing, not a quiet substitution.

Either way, the retained old-stock wicks just earned their shelf space. Keep doing it: every incoming lot contributes a small labelled bag to the retained box before anything reaches production.

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:

Three things to buy for this job

Frequently asked questions