I'm Scaling From 10 Candles to 200 Using the Same Formula — What Production Variables Should I Document Before Assuming the Scale-up Is Successful?

What actually changes between 10 and 200

Ten candles of 200 g is 2 kg of scented wax: 1.84 kg of wax and 160 g of oil at 8% of total weight. You probably made it in one pot, poured it in a few minutes and could picture every step. Two hundred candles of 200 g is 40 kg of scented wax: 36.8 kg of wax and 3.2 kg of oil. After allowing 5% wastage, you need about 42.1 kg, which is roughly 38.7 kg of wax and 3.37 kg of oil.

No single vessel you are likely to own takes that in one go. The 20 kg Electric Wax Melter has a stated capacity of 20 kg, so you are looking at three melts at the very least, or five in a 10 kg melter. Each melt is heated, scented, stirred and poured separately. Each can drift. And the pouring session now runs for hours rather than minutes.

That is why the question is not whether your recipe scales. It does; percentages are percentages. The question is which parts of the process, invisible at 10 candles, now vary between melts and across a long session. Those are what you document.

Keep a reference before you scale

Documentation needs something to compare against. Before the first large melt, set aside three candles from your successful small batch. Label them clearly as the reference, store them together away from heat and light, and do not burn them casually. They are the definition of what your 200 candles should be.

If you no longer have candles from that batch, make a fresh 2 kg reference batch with the same materials before scaling, and approve it by burn test. Scaling from a memory of a good candle is how makers end up arguing with themselves about whether a batch is right.

The variables to record for every melt

The sheet below lists what to capture. It is deliberately more detailed than a recipe card. Some columns will feel unnecessary for the first few melts, and they are the ones that answer the question when something eventually goes wrong.

If your wax or oil packaging carries a batch or lot marking, record it. If it does not, record the date you received it and the pack it came from. The point is to be able to say later, with certainty, which material went into which candles.

Worked example: 200 candles in three melts

You make the 42.1 kg of scented wax as three melts of about 14 kg in a 20 kg melter: 12.88 kg wax and 1.12 kg oil each at 8%. Each melt fills 70 candles on paper and about 66 or 67 after wastage. You number candles 1–67, 68–133 and 134–200, and every candle's number ties it to its melt on the sheet.

On each sheet you record the planned 12.88 kg and 1.12 kg alongside what the scale actually showed. You record the addition temperature from three depths, the stirring time, and a pitcher temperature for every draw. At four points in each melt you weigh three candles. You keep candles from the start, middle and end of each melt: nine samples in total.

After curing all nine with the three reference candles under the same conditions, you burn them side by side. Melts one and three match the reference. Melt two is slightly weaker. The sheet shows melt two was stirred for less time because the team was waiting for jars. Now you know exactly what to fix, and you have not guessed at the fragrance, the wax or the wick.

Make the records easy to keep

A batch sheet that is hard to fill in will be filled in afterwards, from memory, which defeats its purpose. Design it so the numbers are written at the moment they happen.

Print the planned figures in advance

Before the melt, write the planned wax and oil weights, the target addition temperature and the pour window on the sheet. The person weighing then only writes the actual figure beside the planned one, and a mismatch is obvious at a glance.

Keep the sheet at the station

Clip the sheet to a board next to the melter with a pen attached. A sheet kept in the office gets filled in at the end of the day. Protect it from wax splashes with a plastic sleeve if needed.

Name who did each step

Initials beside the weighing, scenting and pouring entries cost nothing. When a second person starts making batches, they are what let you compare methods between people rather than between melts.

Note anything unusual

Leave a blank box for remarks: a power cut, a delayed jar delivery, a hotter afternoon, a pitcher that sat while the phone rang. Most useful explanations for an odd melt come from this box rather than from the numbered columns.

Decide what success means before you pour

Write your acceptance criteria before the first large melt, so the result cannot bend them. Criteria you set afterwards tend to fit whatever happened.

If all five pass for all melts, the scale-up is successful and your records become the written process for the next 200. If one fails, the records show you where. Either way, you have replaced an assumption with evidence.

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