My New Jar Has a Much Thicker Base — Should I Repeat End-Of-Life Burn Testing Even If the Upper Dimensions Are Unchanged?
Aktie
How much of the candle is affected? In a 7.6 cm jar, each centimetre of depth holds about 39.9 g at a labelled 0.88 g/ml. The last centimetre is about 20% of a 200 g candle.
Do I need a different wick? Not as a first move. A new wick rewrites the whole candle to fix its last centimetre. Test the approved wick to the end in both jars first.
How many candles and what cost? Six — three in each jar — all burned to the end. In CSI materials (Natural Soy Pearl, Dark Vanilla, wicks, centering device): ₹1,997.00. See the kit.
Where a thicker base changes the candle — and where it does not
When the only change is a heavier base, the top of the candle is untouched: same internal diameter, same melt-pool area, same wick-to-glass distance. If you pour the same 200 g, it even stands at the same height above the inside floor. What moves is the floor itself. Your title gives no numbers, so this page uses a labelled illustration: a jar 7.6 cm inside and 9.0 cm tall outside, with the base going from 6 mm to 12 mm. The first burns happen several centimetres above that base and are very unlikely to notice it. The last burns happen right on top of it.
| Measure | Old jar (6 mm base) | New jar (12 mm base) | Change |
|---|---|---|---|
| Inside diameter / melt-pool area | 7.6 cm / 45.36 cm² | 7.6 cm / 45.36 cm² | none |
| Height of 200 g of candle | 5.01 cm | 5.01 cm | none |
| Internal depth (outside height − base) | 8.4 cm | 7.8 cm | −0.6 cm |
| Headspace above the wax (depth − fill) | 3.39 cm | 2.79 cm | −6 mm |
| Glass in the base (outside area × thickness) | 33.3 cm³ | 66.5 cm³ | +100% |
| Candle in the last layer (about 1 cm) above the base | 40.0 g | 40.0 g | none — but it now sits on twice the glass |
The table shows why the question in your title is well framed. The upper dimensions really are unchanged, and for most of the candle's life the tests you already ran still describe it. Two things are different. The base contains twice the glass — 33.3 cm³ against 66.5 cm³ in this illustration, a geometric volume, not a thermal measurement. And because the outside height is the same, the fill surface now sits 6 mm closer to the rim, with 2.79 cm of headspace instead of 3.39 cm. The first is an end-of-life question; the second is a small early-burn question worth one look.
Splitting the candle into burn zones
The cleanest way to decide what to retest is to cut the candle into depth zones and ask which zone the change can reach. At 7.6 cm inside and a labelled 0.88 g/ml, every centimetre of depth holds 39.9 g of candle, so the 200 g column is 5.01 cm deep — five layers of about one centimetre.
| Depth zone | Candle in zone | Share of candle | Burned so far | Verdict for a thicker base |
|---|---|---|---|---|
| Layer 1: 0.00–1.00 cm down | 40.0 g | 20.0% | 20.0% | Early burns — KEEP after a short CONFIRM |
| Layer 2: 1.00–2.00 cm down | 40.0 g | 20.0% | 40.0% | Early burns — KEEP after a short CONFIRM |
| Layer 3: 2.00–3.01 cm down | 40.0 g | 20.0% | 60.0% | Middle burns — CONFIRM |
| Layer 4: 3.01–4.01 cm down | 40.0 g | 20.0% | 80.0% | Middle burns — CONFIRM |
| Layer 5: 4.01–5.01 cm down | 40.0 g | 20.0% | 100.0% | End-of-life zone — REPEAT |
Read down the last column. The top two zones — roughly the first two-fifths of the candle — are the least likely to notice a base 4–5 cm below them. The middle zones are worth watching on the ordinary scoring sheet. The last zone, about 40 g, or 20% of the candle, burns directly on the new base, and that is where the retest has to concentrate. It is also the part of the candle your customer burns last, when the jar has been heated and cooled many times and is least likely to be watched carefully.
The early-burn question is the headspace. With the fill 6 mm closer to the rim, the flame on the first burns sits nearer the top of the jar, where it is more exposed to draughts. It is a small change and usually shows nothing, which is why it is a CONFIRM line rather than a REPEAT. If your new jar is also taller, the headspace changes the other way and becomes the main question — the taller-jar post works that case.
The retest matrix for a thicker base
Using the series' four verdicts — KEEP, CONFIRM, REPEAT, NEW — the thicker base is the mirror image of most jar changes: the early lines relax and the late lines tighten.
| Test | Verdict | Reason |
|---|---|---|
| Oil–wax compatibility, cure, cold throw | KEEP | Formula and top surface unchanged |
| Time to full melt pool, early burns | CONFIRM (first 2 burns) | Same pool; headspace 6 mm less |
| Flame, soot, mushrooming, early burns | CONFIRM | Flame slightly nearer the rim |
| Hot throw | KEEP after early CONFIRM | Same pool, same formula |
| Middle burns — pool depth, tunnel ring | CONFIRM | Record as usual |
| Last-zone burns — flame, pool depth, jar readings | REPEAT | Pool now sits on twice the glass |
| Wick tab behaviour at the end (leaning, lifting, flaring) | REPEAT | Tab now rests on a different base |
| Glass-base reading at the end | NEW | Reading at the outside base, never needed before |
| Wax left in the jar when the flame goes out | NEW | Defines usable wax and your end-of-burn instruction |
| Label burn time | CONFIRM | Consumption rate unlikely to change, but usable wax may |
The protocol: six candles, all to the end
Because the change sits entirely at the bottom, a bracket wick is not the first move here. A different wick changes the whole candle — its early burns, its throw, its consumption — to solve a problem that might exist only in the last few burns. Test the approved wick first, in both jars, all the way down. Only if the new base makes the end of life worse do you have a decision to make, and the options are set out below.
| Line | How | Worse than control means |
|---|---|---|
| Flame height at 30 min and at end | Ruler behind the flame | Taller flame near the base |
| Pool depth to glass floor | Marked skewer | Pool reaching the base sooner |
| Tab behaviour | Note: upright / leaning / lifting / flaring | Any movement the control does not show |
| Jar-side reading, lower third | Same thermometer, same point | Higher than control |
| Outside base reading | Same thermometer, jar lifted onto a heat-proof mat | Higher than control |
| Soot on glass | Wipe test, 0–3 | More than control |
| Wax left when burn ends | Jar weight − empty jar weight | Much more or much less than control |
The priced test kit
Built from listed, in-stock CSI sizes on the 24 September 2026 pull, using Natural Soy Pearl Wax and Dark Vanilla as the worked example. Soy Pearl's smallest bag is 1 kg, so a six-candle test lands on two bags.
| Item | Need | Buy | Price |
|---|---|---|---|
| Natural Soy Pearl Wax | 1,159.2 g | 2 × 1 kg | ₹900.00 |
| Dark Vanilla Fragrance Oil | 100.8 g | 1 × 100 g + 1 × 15 g | ₹920.00 |
| Eco Candle Wicks Thin C1 | 6 + spares | 1 × 10 | ₹59.00 |
| Wick Centering Device | reusable | 1 × 5 | ₹118.00 |
| CSI materials total | ₹1,997.00 | ||
| Spare wax after the test | 840.8 g | use for the next test | — |
| Pack | Price | Per kg |
|---|---|---|
| 1 kg | ₹450.00 | ₹450.00 |
| 5 kg | ₹2,124.00 | ₹424.80 |
| 10 kg | ₹4,248.00 | ₹424.80 |
| 50 kg | ₹21,240.00 | ₹424.80 |
| Pack | Price | Per gram |
|---|---|---|
| 15 g | ₹130.00 | ₹8.67 |
| 50 g | ₹410.00 | ₹8.20 |
| 100 g | ₹790.00 | ₹7.90 |
| 500 g | ₹3,840.00 | ₹7.68 |
| 1 kg | ₹7,646.00 | ₹7.65 |
Decision rule: what to do if the end is worse
CSI publishes no numeric flame-height or jar-temperature limits. Judge the new jar against the control, line by line, and against your jar supplier's guidance and the fire-safety standard you work to (ASTM F2417 is a commonly cited US one).
| Result | Decision | What to do |
|---|---|---|
| Every line no worse than control, to the end | PASS | Release; record base thickness in the jar spec |
| Last zone runs hotter or the flame grows near the base; early burns fine | FAIL — end of life | Do not release; the options are an earlier end-of-burn instruction proven by test, a different jar, or a full wick retest |
| More wax left unusable than control | ADJUST | Check tab behaviour; update usable weight and label burn time |
| Tab lifts or leans in new jars only | ESCALATE | Check wick adhesion on the new base — see the wick-adhesive post |
Two of those options deserve a caution. An earlier end-of-burn instruction on the label ("stop burning when … of wax remains") is only acceptable if you have tested that the candle is well behaved down to that line; it is your instruction, written from your data, not a number from us. And a wick change is not a small fix here — it resets the early-burn tests you were able to keep, so it turns this into a full retest. Tab problems on a new base are a production-material question covered in the wick-adhesive post.
Release and record
Base thickness is the jar dimension most often missing from candle records, because nobody sees it once the candle is poured. Add it to your jar specification now, along with the internal depth and the wax left at the end of the full-life burn. That last figure is useful beyond this test: it tells you how much of each candle's weight is usable, and it is the first number to check if a customer ever complains about a candle "ending early".
| Field | Entry |
|---|---|
| Change | Base thickness 6 → 12 mm (measured range on 5 jars); upper dimensions unchanged |
| Held constant | Wax, oil, load, wick, 200 g fill |
| Tests | 3 + 3 full-life, last-zone sheet, early burns CONFIRMED |
| Result | PASS / FAIL — end of life / ADJUST |
| Wax left at end, old vs new | grams, from weighing |
| Label | Burn time and any end-of-burn instruction, from data |
| Retained samples | One unburned candle from each set, dated |
The one-page version of this record is in the change-control form post, and the only-the-jar post gives the general list for any container change. If the new jar also has thicker walls, combine this test with the thicker-glass post; the two changes usually arrive together.
Related jar changes
End-of-life questions are also the heart of two other posts in this cluster. A jar that narrows toward the bottom puts the late burns in a smaller pool as well as closer to the base — the narrowing-jar post — and a taller jar with the same diameter moves more of the candle's life into the lower jar — the taller-jar post. For the geometry behind every jar change, start at the 7.6 → 7.9 cm hub. And if you are still choosing between jars, the alternative-container post includes base thickness in its scoring rule.
CANDLEMAKINGSUPPLIESINDIA supplies raw materials, not jars or burn data. This page advises against the reflex purchase — a new wick — until the approved one has been tested to the end, because a wick change resets tests a thicker base leaves intact.
Wax and oil prices are CSI live pricing, pulled on 24 September 2026; wick and tool prices are those verified for Blog 760 on 10 September 2026, rechecked 25 September 2026. Jar dimensions are illustrations; grams per centimetre, zone weights, headspace and base glass volume are plain geometry from them.
The 200 g fill, 8% test load, 0.88 g/ml wax factor, 5% allowance, three-candle sets, 3–4 hour cycles and 7-day cure are labelled working practices. Natural Soy Pearl Wax has no published fragrance ceiling in this series. CSI does not publish jar dimensions, base thickness, thermal behaviour, wick tab details or numeric safety limits. WhatsApp +91 7397976926 for help, GST invoicing, MSDS or IFRA documentation.
Frequently asked questions
- My Jar Supplier Changed the Internal Diameter from 7.6 cm to 7.9 cm — Is That Difference Large Enough to Require New Wick Testing?
- My Replacement Jar Has the Same External Diameter but Thicker Glass and a Smaller Internal Diameter — Should I Treat It as a New Candle System?
- My New Jar Is Taller but the Diameter Is Identical — Do I Need a Complete Burn Test or Mainly Later-Stage Heat Testing?
- My New Jar Narrows Toward the Bottom — Could a Wick That Is Correct at the Top Become Too Powerful Later?
- My Jar Supplier Is Temporarily Out of Stock — How Do I Choose an Alternative Container That Requires the Least Formulation Redevelopment?
- If I Change Only the Jar, Which Tests Should Be Repeated to Confirm Wick Performance and Container Heat Remain Acceptable?
- I Changed My Wick Adhesive and Tabs Are Now Lifting During Burning — Should Production Materials Outside the Wax Formula Also Be Part of Validation?
- How Do I Create a Simple Change-Control Form for a Small Candle Business That Records What Changed, Why It Changed, Which SKUs Are Affected and What Must Be Retested?
Customer reviews: The six reviews at the top of this page are genuine, published Judge.me reviews left by CSI customers on the product pages named on each card — Eco Candle Wicks, Premium Candle Wicking Needle and Bamboo Wick Holder. They are general product reviews, not assessments of the guidance set out here. Names, star ratings, dates and products are as recorded by Judge.me and wording is unedited. "Verified buyer" appears only on the three reviews Judge.me recorded as verified — Monika Deep, Subhankar Roy and Sneha Tamang; the reviews from Ashwini, LJ and Lalitha Jagan are published but not recorded as verified, and carry no badge.
Figures pulled 24 September 2026, CSI live pricing: Natural Soy Pearl Wax ₹450.00 / 1 kg, ₹2,124.00 / 5 kg, ₹4,248.00 / 10 kg, ₹21,240.00 / 50 kg (no fragrance ceiling quoted in this series). Dark Vanilla Fragrance Oil ₹130.00 / 15 g, ₹410.00 / 50 g, ₹790.00 / 100 g, ₹3,840.00 / 500 g, ₹7,646.00 / 1 kg. Figures verified 10 September 2026 (Blog 760), wick packs rechecked 25 September 2026: Eco Candle Wicks Thin C1 ₹59.00 / 10; Wick Centering Device ₹118.00 / 5; White Matte Glass Jar ₹354.00 / 5.
Non-price figures and assumptions: The 7.6 cm inside, 8.4 cm outside, 9.0 cm outside height and 6 mm / 12 mm bases are illustrative. Area = π × d² ÷ 4; grams per cm = area × 0.88 g/ml (labelled approximation); base glass = outside area × thickness; headspace = internal depth − fill height. The 200 g fill, 8% test load (oil = W × L), 5% allowance, three-candle sets, 3–4 hour cycles and 7-day cure are working practices. CSI publishes no jar dimensions, thermal data, wick tab details, burn results or safety limits. Diwali 2026 falls on 8 November.