I'm Scaling a 1 Kg Candle Formula to 10 Kg for the First Time — Which Temperatures, Mixing Times and Measurements Should Remain Fixed Rather Than Simply Multiplying Everything?

Sort the recipe before you scale it

A 1 kg recipe card usually mixes three kinds of instruction without distinguishing them. Some lines describe properties of the wax and fragrance, such as the load percentage and the temperatures, which do not care how much wax is in the pot. Some describe quantities, which scale in direct proportion. And some describe time, which is really a stand-in for a physical result: the wax is fully melted, the oil is fully mixed, the pour is done. Time-based lines are the ones that break at 10 kg.

Before your first 10 kg batch, rewrite the card with every line placed in one of three columns: keep fixed, multiply, or re-derive. It takes ten minutes and prevents the two classic errors: scaling something that should not move, and copying a time that no longer means what it used to.

What stays exactly the same

Percentages

Fragrance load is a ratio, so it stays at whatever you approved. If your 1 kg test was 8% of total weight, your 10 kg batch is 8% of total weight. The same applies to any additive expressed as a percentage, such as a microcrystalline wax blend inside its stated 1–10% range or Vybar inside its stated 0.5–2%.

Temperatures

Melt, addition and pour temperatures belong to the materials. CSI 468 states a melt point of 50–53°C and a pour of 58–60°C; those numbers are the same whether you are filling five jars or fifty. For waxes without a published figure, use the temperature your wax maker states and your 1 kg test confirmed. What changes at 10 kg is not the target but how hard it is to hit, because a large mass takes longer to arrive and longer to leave.

How you measure

The measuring method is a fixed line too. Weigh fragrance by mass on a tared container, never by volume. Read wax temperature with the probe in the body of the wax, away from the wall and the surface, after a stir. Use the same thermometer at both sizes so any quirk it has is at least consistent.

Tolerances deserve a moment's thought. If you allowed yourself a gram either way on 80 g of oil at 1 kg, the proportional equivalent at 800 g is ten grams either way. Write tolerances as a percentage of the ingredient and convert them to grams for each batch size, so that a tolerance never silently tightens or loosens as the batch grows. Any tolerance you set is your own starting point to validate against burn results, not a published figure.

Jar, wick and cure

The jar, the wick size and the cure period before burning are part of the approved candle. None of them changes because you poured more of it at once. If you plan to change any of them later, treat that as a new formula to test, not as part of the scale-up.

What multiplies, and how to write it down

Masses and counts scale exactly. At 8%, 920 g of wax and 80 g of oil become 9.2 kg and 0.8 kg. Ten kilograms of scented wax fills 50 candles of 200 g exactly, or 48 once you allow 5% for wastage in jugs, spills and top-ups. So your 10 kg card also needs 48 to 50 jars, 48 to 50 wicks and the matching number of wick stickers.

Write the multiplied numbers onto the production card in full rather than writing '×10'. A card that says 9.2 kg and 0.8 kg cannot be misread as 10 kg and 800 g. Ideally, also name the container the oil is weighed into and note that it is tared first, so the person weighing never has to calculate anything on the spot. The second version, a common slip, gives a 10.8 kg batch at about 7.4%.

What must be measured again

Anything your 1 kg card expresses in minutes needs to be established fresh. Here is how each one behaves at 10 kg.

Melting time. CSI's Electric Wax Melter (Imported) states that it melts 10 kg of soy wax in approximately 30 minutes at 100°C. That is a maximum-setting figure for melting, not a recommended processing temperature, and a double boiler with the same 10 kg would take far longer. Record your own time to a fully melted, clear batch.

Cooling to addition temperature. Ten kilograms loses heat slowly. Where 1 kg reaches the addition range in a few minutes off the heat, 10 kg may take much longer. Do not guess from the clock; read the thermometer.

Stirring time. Your 1 kg stir may have been thirty seconds with a spoon. At 10 kg the same time is unlikely to reach the base and edges. Define mixing by an end point, such as the base and walls scraped and no streaks visible, and note how long that took. That note becomes your minimum for next time, a starting point to validate rather than a rule.

Pouring time. Fifty candles take far longer than five. Measure the time from first to last jar and the wax temperature at both ends. That tells you whether your pour window is realistic or whether the batch needs to be split.

Running the first 10 kg batch as a measurement exercise

Your first 10 kg batch has two jobs: make sellable candles, and collect the time-based numbers the new card is missing. Treat it as a measured run.

Once those blanks are filled and the three labelled candles burn alike, the card is a production card. Keep the 1 kg version too, for testing new fragrances before they reach the large batch.

On the second 10 kg run, use the first run's times as expectations rather than instructions. If melting, cooling or pouring takes noticeably longer or shorter, something has changed, whether room temperature, a different wax pack or a melter set differently, and the card has just told you to look.

Where this page fits

CSI already has guides that cover parts of this question. This page takes the production-floor angle; these go deeper on the rest:

Three things to buy for this job

Frequently asked questions