# Stick Elevator Mechanics (Balms & Deodorants): Screw Lead Pitch, Backlash, and Molten Fill Sealing
TL;DR — Balms, deodorants, and lipsticks all ride the same stick format: an elevator screw raises a cup, the screw's lead pitch sets how far one turn takes it, and backlash is the lost motion that appears the instant the direction reverses. The catalog records the lipstick stick format at 28 models with 3.7 g and 4.1 g standard fill tiers and Ø12.1 mm and Ø12.7 mm mechanisms; balm and deodorant sticks are the same format class applied to other formulas. Screw and molten-fill mechanics here are engineering guidance — configured per project, with torque and drop tests as the capability-level verification hooks.
Why: The Stick That Screws Up
A stick product has no pump and no valve — the mechanism is the elevator inside the barrel, and the customer judges it on every single turn.
- Elevation is the product experience. The platform must rise a consistent amount per turn so the stick meets the application surface at a predictable rate;
- Backlash is the silent flaw. Reverse play turns a turn into a gap, and on a deployed stick it shows as wobble or dead travel;
- Fill decides the first turn. A stick is poured molten onto the elevator; how it seals and re-solidifies around the cup decides whether the mechanism feels right from the very first twist;
- The format is recorded; the formulas are not. The catalog records the lipstick stick format; balm and deodorant sticks are the same format class applied to other formulas.
How: The Screw, the Play, and the Pour
3.1 Screw lead pitch: advance per turn
The elevator screw converts rotation into lift: one turn advances the platform by the screw's lead. A coarser lead moves more stick per turn — faster application, larger steps; a finer lead moves less — slower, more precise. The right lead is a joint trade-off with stick diameter, product softness, and user habit, so it is configured per project. The catalog publishes no lead values, thread counts, or turns-to-empty figures.
3.2 Backlash: the lost motion at reversal
No screw-nut pair mates without clearance, and that clearance surfaces as backlash: twist the collar up and the mechanism responds; twist in reverse and the first degrees of motion are spent taking up the play before the platform actually moves. On a stick this is not a nicety — during application, weight presses the stick back into the cup, and uncontrolled play lets it settle or wobble. Managing backlash is a fit-and-tolerance exercise across the screw, the nut body, and the cup, resolved per project.
3.3 Molten fill sealing: the pour and the re-freeze
Stick formats are typically filled hot: melted formula is dosed into the shell around the raised cup, then cools and re-solidifies into the final stick. Three consequences follow. The seal between formula and cup decides whether product creeps back toward the mechanism. The cooling profile decides air traps and shrink voids under the stick. And test-turn behavior at room temperature is the honest measure of the fill. Fill temperature, cooling curve, and cup geometry are project-level process parameters — none are published.
3.4 The verification hooks
Torque test and drop test are the two capability-level capabilities on this format in the quality program. Torque covers the mechanism's behavior under turn and retention loads — the collar's resistance and the cup's grip. Drop test covers the format in transit, when a stick that lands on its lid changes the first application. Both are capability-level with no published parameters; acceptance is judged per project.
<pre class="language-mermaid"><code>flowchart LR
A[Stick format<br/>lipstick tube 28 models<br/>Ø12.1 / Ø12.7 mm] –> B[Elevator screw<br/>lead pitch per project]
B –> C[Backlash control<br/>fit and clearance]
C –> D[Molten fill + re-solidify<br/>per-project process]
D –> E[Torque test]
D –> F[Drop test]
E –> G[Verified per project]
F –> G
</code></pre>
What: Verified Program Data and the Verification Hooks
- Lipstick tube family: 28 recorded models — the catalog's stick format.
- Standard fill tiers: 3.7 g and 4.1 g, per the published lipstick category data.
- Mechanism diameters: Ø12.1 mm and Ø12.7 mm, in PP + anodized aluminum construction (as published on the lipstick category page).
- Shell materials: ABS, PET, PETG, AS, and PMMA recorded.
- Component record: lipstick tube/body, lipstick cup/base, and lipstick mechanism are recorded component families.
- Format-class boundary: balm and deodorant sticks are the same format class as the lipstick stick, applied to other formulas — the catalog records only the lipstick format.
- Verification hooks (capability-level): torque test (mechanism behavior and retention) and drop test (transit) — no parameters published, acceptance configured per project.
Gotchas
- Balm and deodorant sticks are not catalog families. The record holds the lipstick stick format; balm and deodorant sticks are the same format class applied to other formulas — never presented as recorded catalog models.
- Lead pitch is not published. Advance per turn, thread counts, turns-to-empty — all per-project values; quoting one as program data overstates the record.
- Backlash only appears on reversal. A mechanism that feels solid twist-up can show dead travel twist-down; test both directions under load.
- The pour changes the mechanism. What seals hot is not what the customer turns cold; first-stroke and re-solidification behavior deserve a check under the final formula.
- Ø12.1 mm and Ø12.7 mm are mechanism diameters, not formula sizes. They anchor the recorded mechanism family, not any balm or deodorant fill.
- Capabilities, not thresholds. Torque and drop are capability-level; pass/fail values are per-project verification outcomes, not published specs.
Related Resources
- Category: Lipsticks
- Related insights: Cosmetic Pen Dispensing Mechanisms · Refillable Lipstick & Compact Mechanisms · The 12-Test Lab Matrix
- Quality & Testing Capabilities · Customization — screw, cup, and fill configuration