Should Candidate Waxes Be Evaluated Immediately, After One Week and After Temperature Cycling Before I Choose a Winner?

Yes — and the winner is chosen on its worst checkpoint, not its best

The short answer is yes: judge every candidate wax on pour day, at 48 hours, at one week, after a temperature cycle and again at about a month, and do not crown a winner until the cycle checkpoint is in. The reason is not thoroughness for its own sake. Each checkpoint catches a different family of wet spot. Spots that appear the moment the candle sets usually point at the process — cold glass, fast cooling, a dirty or handled jar. Spots that open over the first week are commonly described as the wax still firming and contracting as it crystallises. Spots that appear only after warm-and-cool swings are a courier and storage problem. A wax can be best at one checkpoint and worst at another, and only the last two checkpoints resemble the life your candle actually lives.

So the useful question is not "which wax looks best?" but "which wax is still acceptable at its worst checkpoint?". For most clear-glass lines shipped across India that worst checkpoint is the temperature cycle. For a candle that will sit in inventory for weeks before it is sold, it may be the one-month look, which the one-month storage post owns. Either way, the 48-hour photograph is the first entry in the record, not the verdict.

The worked example on this page uses the Yankee Glass Jar 130 ml with clear cap — a clear jar whose fill weight CSI does not publish — so the maths runs on a labelled example fill of 100 g: 8 g of Lavender and 92 g of wax at 8%. Weigh one filled jar of your own and replace the figure. The jar choice is deliberate: smaller jars are cheap enough to split every arm into twins, and the twin design is what lets the checkpoints tell you something rather than just adding photographs.

Why one checkpoint misleads

A wet spot is commonly described as an area where the wax has separated from the glass, leaving a thin air gap that looks darker through clear glass. Separation needs a force, and the forces change over time. In the first hours the wax is cooling and shrinking away from glass that may be cooler or warmer than it. Over the following days many soy waxes are described as continuing to set and rearrange their crystal structure, which can open gaps that were not there on pour day — the post on spots that appear after a week is built around exactly that. And every time a finished candle warms and cools, the wax and the glass expand and contract by different amounts, which is the mechanism behind spots that appear only after delivery or storage.

Because each of those forces acts at a different time, a ranking taken at one moment is a ranking of how far each wax has got along its own timeline, not of where it ends up. Two waxes can both be spot-free at 48 hours; one may open small spots by day seven and stop there, while the other stays clean until the first warm afternoon and then pulls away along a third of the wall. If you choose at 48 hours, you choose by coin toss between those two outcomes. CSI publishes no adhesion or wet-spot data for any wax, and the three container-wax pages that describe adhesion — Chunks, CSI 464 and CSI 468 — all make essentially the same claim, so the only way to see the timeline is to photograph it.

There is a second reason to keep looking: process faults and wax behaviour look alike on pour day but separate later. A jar poured onto a cold stone slab, or under an AC vent, can spot immediately whatever the wax. If every arm spots on pour day in the same tray positions, the culprit is the room — an AC draught or a cold stone surface — not the candidates. A wax-driven difference tends to persist or grow at later checkpoints while the position pattern fades into the background.

The twin design: cycled jars and room jars from the same pour

If you cycle every jar, you cannot tell whether a spot that appears around day twelve came from the cycle or would have appeared anyway with time. The fix costs nothing extra: split each arm into twins. Of the six jars per arm in this example, three go through the temperature cycle after the 7-day photographs, and three stay on the shelf at room temperature. At the post-cycle checkpoint you compare each cycled jar with its room twins. A cycled jar that worsens while its twins stay put convicts the cycle. Cycled and room jars that worsen together point at time — slow setting — and the cycle may be innocent.

The cycle settings are a labelled example, not a standard: 8 hours warm and 16 hours at room temperature, repeated 5 times, which takes 5 days. "Warm" means a measured, recorded temperature that you have logged on your own courier route or storage room — for example a closed cabinet or a parked car with a min/max thermometer inside — and it must stay well below the melting point of every wax in the test (CSI 468's page states 50–53°C, so a warm phase that approaches that is not a cycle, it is a melt). The temperature-cycle test post builds the cycle from your logged route and decides how many warm settings you need before approving a pan-India formula.

The scoring sheet: one row per jar, one column per checkpoint

Score every jar at every checkpoint on the same written house scale. The example scale below runs from 0 (no wet spot from any of the four sides) to 4 (pull-away over a third or more of the wall); add an estimated percentage of visible glass area, measured with a printed grid or a marked acetate sleeve held against the jar. The scale is yours — there is no industry figure — but once written it does not change between checkpoints, or the timeline means nothing. What to record when comparing waxes gives the full record.

Two derived numbers per arm drive the decision. The first is the arm's worst checkpoint: the checkpoint where its mean grade is highest. The second is the cycle effect: the mean grade of its cycled jars after the cycle minus the mean grade of its room jars at the same date. A wax with a large cycle effect is sensitive to temperature swings in your jar, whatever it looked like on pour day. A wax with a small cycle effect but rising grades in both twins is still settling — give it the full 30 days before deciding.

The priced checkpoint kit

Here is the three-arm, twin-split round priced with listed, in-stock CSI packs. Each jar takes 8 g of Lavender and 92 g of wax at the example 100 g fill. Each CSI arm needs 568.6 g of wax including a 3% pour-loss working allowance. The Lavender covers all three arms including your control, so oil is constant and only the wax changes. Your own wax for the control arm is not in the CSI total.

Note what the round does not include: a warming cabinet, a min/max thermometer or data logger, a lint-free cloth. CSI does not list them, so they are your own items or non-CSI purchases — any price you put on them is your quote, not ours. The Pen Thermometer (₹354.00) measures wax, not glass or air; use it for pour temperatures and record every one.

What the schedule costs in time, and how to fit it before Diwali

The materials are the small cost. The real cost of five checkpoints is time — calendar time and photography time. Calendar first: poured on Friday 9 October, the cycle checkpoint falls around 21 October and the month checkpoint on 8 November. Diwali is Sunday 8 November, 30 days after that pour. A festive decision therefore has to be made at the cycle checkpoint, with the room twins carrying on to day 30 as confirmation — which is a reason to pour this week rather than next.

Photography second. Eighteen jars × four sides is 72 photographs per checkpoint and 360 across all five. At a labelled example of 30 seconds per photograph, including turning the jar and checking focus, that is about 180 minutes of camera work over the month, before scoring. Replace the 30 seconds with your own timing. If the time is the constraint, cut checkpoints in this order: drop day 2 first (day 0 and day 7 bracket it), never drop the cycle.

For a sense of what the candles themselves cost per jar in this format: at the example 100 g fill, with wax at the 1 kg rate, Lavender at the 100 g rate (₹5.40 a gram), an Eco Thin C1 wick at ₹5.90 and the jar at ₹47.20, a CSI 464 jar costs ₹142.98 and a Natural Soy Pearl jar ₹137.70 in materials, excluding labour, packaging, freight and GST. The difference between the waxes is ₹5.28 a jar — far smaller than the value of a jar that has to be hidden behind a label.

The decision rule across checkpoints

Apply from the top after the post-cycle photographs, and again at day 30. Stop at the first line that is true.

Notice that no line ends in a bulk purchase. Checkpoints narrow the field; the pilot decides it. Six jars per arm, even clean through every checkpoint, are too few to prove a low wet-spot rate — the jar-count post shows the arithmetic, and the acceptable-percentage post shows how many pilot jars your own threshold demands.

The CSI products in this round

Where this fits in the qualification

This page owns the schedule — when to look and how to read changes between looks. How many jars per wax sets the arm size; the one-month storage post extends the last checkpoint into inventory; the pilot post takes finalists to 50–100 candles; and the series capstone lays out the whole path to a bulk purchase. If your spots only ever appear after delivery, start with the courier-cycling hub.

Frequently asked questions