I’m Launching 10 Fragrances in One 8 cm Jar — How Many Wick Sizes Should I Initially Test with Each Fragrance Before Narrowing the Range?

Sizes per fragrance is a budget decision

The question sounds technical, but the answer is mostly a budget. Every wick size you test with a fragrance costs two candles (one candle can be a pouring accident), and at 8 cm each candle is a 200 g fill in the worked example: 16 g of oil and 184 g of wax. Multiply by ten fragrances and one extra size per oil is 20 more candles, 4,000 g of candle and twenty more jars.

Oil is where it bites first. Two sizes use 64 g of each fragrance; three use 96 g. A 100 g bottle covers either, but three sizes leave only 4 g, too little for one retest candle, while two leave 36 g, enough for 2 more. So the three-size plan quietly commits you to a second bottle of every oil that needs a retest. For ten oils at 100 g, the first round of bottles is ₹4,433.68 either way.

Against that, too few sizes has its own cost. A two-size bracket that is centred in the wrong place produces two fails in the same direction for an oil, and the answer then needs a whole new round: another pour, another cure, another three burns. The closure rule from the adjacent-sizes post applies here too: a chosen wick should sit between a documented fail on each side, or between a fail and the end of the range.

Two rungs or three at 8 cm, on CSI's real rungs

First, the jar. CSI lists no jar at 8 cm (its glass listings with a stated diameter cluster at 6, 7 and 10 cm), so this is your jar from your supplier, and the inside diameter matters more than the label. If 8 cm is the outside, a 0.35 cm wall (our assumption) leaves 7.3 cm inside, a pool of 41.85 cm²; if 8 cm is the inside, the pool is 50.27 cm², 20% more. Measure at the rim, middle and near the base. Either way the jar has about 34% more pool than a CSI 7 cm listing (31.17 cm² on the same wall), so a 7 cm result does not transfer.

Then the rungs. CSI sells three sized, tabbed single wicks: Eco C1 and C2 (no size or jar range stated on the page in the text we captured) and Cotton Braided ("engineered for large-diameter candles exceeding 8 cm"). That gives two honest designs:

Why not add 2 × C1 as a fourth size? Because it isn't a size; it is a different candle, with two flames and a spacing to choose. At 8 cm it belongs to a separate test once Cotton Braided has been under for an oil (the single-versus-double hub for wider jars). For a ten-oil launch, keep the sizes to the three single rungs and treat "under on Cotton Braided" as a flag, not a fourth column.

The sizes-per-fragrance calculator

Three plans, all with ten oils at 8% in a 200 g candle, two candles per size, CSI 464 at the 10 kg price and each oil from a 100 g bottle. Plan C's figures include one worked-example oil that needs a dropped size back. Costs exclude jars, labour, freight, packaging and GST.

Plan C costs ₹2,102.33 less than plan B in materials and saves 12 candles; it costs 8 candles more than plan A. Per candle, the wick is the smallest line: a 200 g Lavender candle on C2 is ₹189.20 of oil, wax and wick, and on Cotton Braided ₹191.76. So an extra size never costs much in wicks; it costs whole candles, at roughly that figure each plus a jar and bench time, and for three-size oils a second bottle when anything needs a retest.

The narrowing rule: three oils, same direction

Plan C works because of one rule, applied after every screening (burn 3) and counted across waves. It is our judgement, chosen so that a size is dropped only on evidence that is hard to explain away.

The worked example, wave by wave

Wave 1 (three rungs, 18 candles): Citrus Lemon, British Rose and Dark Vanilla Oud, chosen to be as different as the list allows (a bright citrus, a "fresh, dewy" rose, and, to our reading, the heaviest notes on the list). Illustrative result: C1 under for all three; C2 passes for Citrus Lemon and British Rose; Cotton Braided passes for Dark Vanilla Oud and is over for Citrus Lemon. C1 has now failed three oils the same way, so it is dropped.

Wave 2 (two rungs, 28 candles): the other seven oils on C2 v Cotton Braided. Illustrative result: Eucalyptus Spearmint is over on C2, towards the dropped rung, so C1 comes back for it alone (2 candles). Everything else lands on C2 or Cotton Braided. Ten oils, 48 candles, and every winner has a documented fail on at least one side.

Days to a decision, and Diwali

Candles are only half the calendar; the other half is how many you can burn at once. The worked example assumes a bench of ten candles burning at a time, each for one 4-hour session a day, within sight, in still air; a 7-day cure; screening as burns 1–3; and full life as 7 sessions, from a measured 7 g an hour and a stop at 30 g left, weighed (both are placeholders; measure yours). One candidate size per oil goes on to full life.

On those assumptions all three plans finish before Diwali if you start this week, and plan A is the fastest. Its speed has a condition: its two sizes must be centred correctly. If C2 turns out to be over for, say, four light oils, they need a C1 round (another pour, cure, three screening burns and four more sessions), which moves the last decision to about day 33 and brings plan A to 48 candles, the same as plan C. The difference is evidence. In re-centred plan A, every oil that passed on C2 still has no smaller fail on record, so you don't know whether a cooler wick would have done. In plan C, wave 1 documents both sides directly and the three-oil rule carries that evidence to wave 2, for two more days. If you already have evidence for this jar, from the wick-matrix hub or a collection policy run on it, plan A is the sensible choice; if the jar is new to you, plan C.

What to buy, and what to skip

Five items, chosen on page statements, price and stock on 29 September 2026; CSI publishes no wick-performance data, so nothing is ranked on burn results. Skip for now: 500 g or 1 kg of any of the ten oils (no plan uses more than 96 g of one), a 500-pack of any wick, and Performance Wooden Wicks (₹590.00 for 10), a single listing with no sizes to bracket.

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