Two Candle Jars Both Hold 200 g but One Is Tall and Narrow While the Other Is Short and Wide — Why Can They Require Completely Different Wick Systems?

Same grams, two different candles

Take our worked example: a jar 6.0 cm inside and a jar 9.0 cm inside, each filled with 200 g of Luxury Soy Wax CSI 464 at 8% Jasmine (16 g oil + 184 g wax). At a rule-of-thumb 0.9 g of wax per ml, the narrow candle stands about 7.86 cm deep with a 28.27 cm² pool. The wide one stands about 3.49 cm deep with a 63.62 cm² pool, 182.25 times the area. Why a wider, shallower pool asks more of a single wick is the physics of the tall-narrow versus short-wide post, and how +50% weight translates into area is the 200 g to 300 g mismatch table. This page takes the physics as given and plans the testing.

What matters for planning is that the two candles differ in three ways at once. Pool: the wide jar needs more melting power at the surface; with two wicks, each faces 31.81 cm², close to the narrow jar's 28.27 cm². Depth: the narrow jar has more than twice as much wax column for the flame to travel down, and the last few centimetres sit inside a tube of glass that has been absorbing heat for hours. Life: the narrow candle burns for many more sessions before its final third, so its problems surface late in the calendar; the wide candle's surface early.

That is why "completely different wick systems" is often literally true. The narrow jar may be a single C1 or C2 for a dozen sessions. The wide jar may be two C1s for four. Same oil, same wax, same load, same 200 g, different answers, and neither result tells you anything about the other.

Measure first: which jar is which

"Tall" and "wide" are not measurements. Before you plan anything, measure each jar inside at rim, middle and base, twice at right angles, and weigh water to your fill line. If a jar tapers, the pool you test at the top is not the pool you will have near the bottom; that is its own problem, and worth knowing before the bracket starts.

Whether the figure to choose a wick by is the capacity or the inside diameter is the 200 ml, 7 cm question. Here the answer is assumed: inside diameter for the bracket, weighed fill for the grams.

Two brackets, run side by side

Hold everything except the wick build: same CSI 464 bag, Jasmine at 8% on total weight, the same pour temperature (the CSI 464 page states 80°C–90°C; if your jar states a lower hot-pour limit, the lower figure governs), one cure, one still room. Within each jar vary one thing. Across the jars nothing is being compared: you are running two experiments on the same bench to share a calendar, not one experiment with two jars.

Three candles per arm, not two, because both jars carry a risk that one odd candle could hide: the tall jar's late heat and the wide jar's two-wick balance. The 3.5 cm spacing is geometry that leaves each flame 2.75 cm from the wall; where to place two wicks before comparing sizes is the 9 cm placement post. If W2 leaves a strip between the pools, that is a spacing finding, not a size verdict. And if you want to know which is better in a wide jar, one larger wick or two smaller ones, at 8.5 cm, that comparison has its own page: one or two wicks at 8.5 cm.

The test-hour budget: sessions to full life

A bracket is not finished until its candles reach about 1 cm left, so the cost that matters is how many valid sessions each candle needs. That depends on how much wax sits above the stop line and how fast the candle burns it. Measure the rate: weigh each candle before and after its first two sessions and divide by hours. Our worked example assumes 5 g per hour for the single wick in the tall jar and 9 g per hour for two C1s in the wide jar; yours will differ, and the budget should be redone with your figures.

The tall jar needs 3 times as many sessions per candle. Burn one session per candle per day with a full cool-down overnight (our judgement; never stack sessions on a warm candle) and, after a 7-day cure, the wide bracket is finished on day 11 and the tall bracket on day 19. Run both on one bench and the wide jar's answer arrives eight days before the tall jar's. If the wide jar used one Cotton Braided at a slower rate than our 9 g per hour, it would need more sessions; re-run the budget once you have weighed the first two sessions of each arm.

For a calendar: Diwali is 8 November 2026, 40 days from 29 September 2026. A bench poured this week reaches the tall jar's last session about 19 days later, which leaves room for one retest round, but not two. Budgeting a much larger commercial programme the same way, in grams per hour and shifts, is the 12 cm test-count budget; the 7 cm full-life calendar is the full-life calendar post.

Late burn: where each jar fails, if it fails

Both jars can pass the first three burns and fail later, but not in the same way. These are tendencies to watch for, not predictions; neither CSI nor anyone else can tell you from geometry alone which one your candles will show.

For the tall jar, why a flame that behaved at the top grows halfway down is the flame-grows-halfway post, and what only appears in the second half of a candle's life is the second-half problems post. For the wide jar, when the bottom of a multi-wick candle becomes hot is the multi-wick bottom-heat post. Read them before you approve either jar on its first few sessions.

Twelve candles in grams, wicks and rupees

Per candle before the jar: tall on C1 ₹168.06, tall on C2 ₹171.60; wide on Cotton Braided ₹174.16, wide on two C1s ₹173.96. The wick choice moves the cost by a few rupees; the shape decision moves the test calendar by a week. Costs exclude labour, freight, packaging and GST.

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. Candle counts in the oil table use 16 g (200 g) and 12 g (150 g) of oil per candle at 8%.

Frequently asked questions