I Have 25 Kg of Scented Wax That Does Not Match My Approved Test — What Should I Investigate Before Attempting to Correct or Rework It?

Define exactly how it misses

Before you think about rework, pin down the mismatch in words that point to a cause. Is the scent weaker but the same character? Stronger? A different character altogether — sharper, flatter, missing its top? Is the colour darker? Is the surface frosted, the set different, the burn tunnelling or sooting? Each of these has a different family of causes, and only some can be corrected once the oil is in the wax.

Make the comparison fair. Pour a few test candles from the batch, and pour a fresh reference from the approved formula at 500 g. Cure both for the same time, burn them in the same room, code them blind, and judge by smell only. If the batch candles and the fresh reference turn out to match, the problem may have been the old reference candle, not the batch.

While you work this out, keep the 25 kg set and covered rather than molten. Scented wax held hot for days keeps losing its lightest notes, and a batch you leave in the melter overnight "just in case" may have changed by the time you decide what to do with it. Label it HOLD, note the date and time it set, and keep it away from wax that is cleared for production.

Write the mismatch down in one sentence before moving on — for example, "same lavender character, noticeably weaker hot throw at day 7, colour and surface normal." That sentence already rules things out: a normal colour argues against overheating of a vanillin oil, and an unchanged character argues against the wrong bottle. Each fact you record now narrows the rework choices later.

Reconcile the record before you touch the wax

This is the step most makers skip, and it is the one that decides whether rework is even possible. Take the batch record — or reconstruct it — and check the arithmetic and the physical evidence.

The bottle is your best witness. If you opened a 1 kg bottle and a second one, weighed both before starting, and weigh what remains now, you know how much oil really went in — whatever the record says.

Worked example: three possible outcomes

Take a 25 kg batch planned at 8% of total weight: 23 kg of CSI 464 and 2 kg of Lavender. At the 10 kg pack price of ₹5,074.00, wax is ₹507.40 per kg, so 23 × ₹507.40 = ₹11,670.20. Lavender in 1 kg bottles is ₹5,221.00, so 2 × ₹5,221.00 = ₹10,442.00. The batch holds ₹22,112.20 of wax and oil.

Outcome 1: the record shows 8% of wax

The bottle weigh-back shows 1.84 kg of oil used. Someone calculated 8% of the 23 kg of wax instead of 8% of the total. The batch is 24.84 kg at 7.41%, and adding the missing 160 g brings it to 25 kg at 8%. Oil cost: 0.16 × ₹5,221.00 = ₹835.36. For the 1 kg trial, the top-up is 160 g ÷ 24.84 kg = about 6.44 g per kg of batch wax.

Outcome 2: the record shows an over-dose

Suppose the weigh-back shows 2.5 kg of oil in 22.5 kg of wax — 25 kg at 10%. To return to 8% you need total weight W where 2.5 ÷ W = 0.08, so W = 31.25 kg: add 6.25 kg of unscented CSI 464, costing 6.25 × ₹507.40 = ₹3,171.25. The batch now fills about 156 candles of 200 g instead of 125, so you need 31 more jars and wicks and a buyer for them.

Outcome 3: nothing adds up

The weights reconcile, the oil is right, but the character is flat. The thermometer log shows oil went in far hotter than your validated point because the melter display read low. No quantity is missing, so there is nothing to top up; the lost top notes cannot be put back. This is a write-off or a repurpose, not a rework.

The rework options and their honest limits

Blending down enlarges the problem as well as solving it: more wax to pour, more candles to sell, and a new formula that has never been validated at that exact load. Repurposing to wax melts works only if the scent is right and the fault is about the candle format; container soy may be too soft for clean release from a mould, so that product needs its own testing too.

Put rough numbers on each route before choosing. A top-up in Outcome 1 costs ₹835.36 of oil plus one remelt of labour and power. A blend-down in Outcome 2 costs ₹3,171.25 of wax plus 31 extra jars and wicks, and it only pays if you can sell those candles. Repurposing costs new moulds, packaging and a round of testing for a product you may not have planned to sell. If the sum approaches the batch value, the numbers are telling you to write off.

When to write off, and how to stop it recurring

Write off when the oil is wrong, when the fragrance has been overheated, or when two controlled 1 kg trials fail. Record the cost — in this example up to ₹22,112.20 of wax and oil — in your production costing so it influences future batch-size decisions rather than disappearing.

There is also a quiet cost to rework that never shows on an invoice: attention. A day spent rescuing one batch is a day not spent producing a good one, and a reworked batch always carries a little more doubt at release. That is a reason to keep rework for clear, recorded quantity errors and not to make it a habit.

Prevention is mostly arithmetic and weighing. State the percentage basis on the batch sheet in words: "8% of total weight — 23 kg wax, 2 kg oil." Weigh oil bottles in and out. Log temperature from a separate thermometer, not the melter display, and write the time oil went in and the time the last jar was poured. With those four entries, the next mismatch can be diagnosed from paper in minutes.

Where this page fits

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

Three things to buy for this job

Frequently asked questions