I Want to Make a 150 g Premium Soy Candle in a 7 cm Jar — Which Candle-Making Raw Materials Do I Need From Wax to Wick?

The jar that states 7 cm — and what "outer" means

Container first, always, and for once the brief and the catalogue agree. The 150 g apothecary family is the small cluster of CSI containers whose pages publish a dimensional block rather than a capacity alone. The Clear Glass Jar with Golden Lid (150 gram) states "Height 8cm, outer diameter 7cm", "150g fill capacity" and "Safe for hot pour up to 85°C". Its coloured siblings go further and give three figures: "Height (with lid): Approx. 8 cm · Diameter (outer rim): Approx. 7 cm · Base diameter: Approx. 6.5 cm · Fill capacity: ~150 gm".

Now the important word. Every one of those pages says outer rim. Your wick does not burn the outside of the glass; it burns a disc of wax whose diameter is the inside measurement at your fill line. On a thick-walled apothecary vessel with a curved silhouette, the inner surface diameter is meaningfully smaller than 7 cm, and the base diameter of 6.5 cm on the coloured versions tells you the shape is not a straight cylinder. So the jar page has given you a genuine, useful, published starting point — and it has still not given you a wick.

The wax, and the 85°C cross-check

Here is a small piece of engineering you can only do when both pages publish numbers. The jar states it is safe for a hot pour up to 85°C. Premium Coconut Soy CSI 468 states a pour temperature of 58–60°C. That is 25 to 27 degrees of headroom, which means the wax cannot stress the glass at its own stated pour window. Compare that with Luxury Soy Wax CSI 464, whose page states a pour temperature of 80–90°C: the top of that band sits above the jar's stated ceiling, so if you choose that wax for this jar you pour at the bottom of the wax's range and say so on your recipe card.

The fragrance and its load

Fragrance is the third decision because it sets a second ceiling, and that ceiling is usually lower than the wax's. CSI 468 states up to 13%; British Rose states "up to 10% for soy wax" with a cure of 48 to 72 hours. Ten per cent governs. Start at 8% of total wax weight so that a quiet first burn leaves you a documented route upward rather than a dead end, and remember the two conventions: 8% of total wax weight in a 150 g fill is 138.9 g of wax plus 11.1 g of oil, which is 7.4% of the finished candle. Write down which convention you used.

Note the last row, because it is the one that changes a decision. Vanilla Bean's page is unusually candid: 2.5% vanillin with "potential discoloration; test with lighter waxes". In a clear glass jar with a pale wax, that is a visible risk you should design around rather than discover. The four oils above it all state 0% vanillin or no vanillin, which is why they suit a jar the customer can see through. Which fragrances behave that way is set out in which candle fragrances are least likely to discolour white wax.

The wick, and the two pages that rule themselves out

You have a jar that states 7 cm. You might reasonably expect a wick page to state 7 cm back. Two CSI wick pages state a diameter, and here is the awkward arithmetic: Cotton Braided Wicks Ready Made is "engineered for large-diameter candles exceeding 8 cm" — wider than this jar — and Eco Candle Wicks Loose is "designed specifically for 2 inch diameters", about 5.08 cm — narrower than this jar. Both pages have told you honestly that they are not the answer. The workhorse Eco Candle Wicks C1 and C2 state no diameter at all, and Performance Wooden Wicks state none either.

Which leaves the method that the whole series is built on: buy a bracket and test it. CSI lists two Eco cotton sizes, so an honest test of this jar is C1 against C2, with wooden wicks as a third candidate of a different type rather than a third size. Ten of each cotton size and a sheet of stickers is ₹247.80 plus ₹100 — less than the cost of two jars — and it is the only part of this specification that money alone cannot buy.

The costed 20-candle specification

Twenty candles, because the jar's largest listed pack is twenty and because twenty is enough to split across two wick candidates with ten each. Quantities include a labelled 5% wastage allowance for spills, top-ups and pot residue — a planning figure, not a published specification — and are rounded up to packs CSI actually sells.

Pouring the run at 58–60°C

Rounding, wastage and the 5 kg trap

Twenty candles need 2,778 g of wax. With a 5% wastage allowance that is 2,917 g. CSI sells CSI 468 in 500 g, 1 kg, 5 kg and 10 kg, so your realistic options are 3 kg made of singles at ₹650 a kilo, or the 5 kg bag at ₹637 a kilo. The 5 kg bag is genuinely ₹13 cheaper per kilo. It also leaves 2,083 g of wax sitting idle — about ₹1,327 of stock — in a formula that has not yet passed a burn test.

The general rule that falls out of this table is worth carrying into every future order: move up the pack ladder one line at a time, and only for lines the burn test has settled. The wax is usually the first line to graduate, because once the wick and load are fixed you will keep pouring the same wax for months. The fragrance is usually the last, because a range expands by adding scents, not by adding waxes. Above the listed packs — and CSI's largest listed fragrance pack is 1 kg — pricing is quoted on WhatsApp; the listed per-kilo figures are the ceiling, and we are not going to guess what a quote will say.

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