Release Powder in Undercuts — Food Is No | RUUIPON

A dust of talc, mica, or a named craft powder in a deep undercut can break vacuum and reduce tear on a *craft* PU or plaster peel. It is not a substitute for the RUUIPON Mold Structure Decision. If a 10A–20A glove cannot peel the hook without tearing, you need a split, a plug, or a core — not more powder. We would not put powder in a chocolate, gummy, ice, baking, or popsicle well. Food cavities stay dry: no grease, no tin, no pantry dust. Powder becomes part of an article you did not extract under 21 CFR 177.2600.

RUUIPON designs peels in Bao'an since 2018. Prototype 3–7 business days after CAD lock. MOQ 20 pieces per design. USD $50 when CAD scope applies. [email protected] · +86 135 3006 2969. LSR *parts*: wydsilicone.com.

Does not apply when you are powdering a *master* so platinum doesn't grab a porous print (that's sealer/release-on-pattern), when the dump is already a two-part with a designed land, or when "powder" means a gummy sanding sugar after demold. Don't treat baby powder as a food-contact release.

Powder is a last craft aid, not a DFM

Confirm the empty well under raking light. If you see a hook, closed letter, or bail, Structure Decision first: flat back → open-back. Else peel without tearing? If no → two-part / plug / core. Large wet dump → mother mold. Powder will not open a rigid epoxy hook. Raising Shore A makes the hook tighter.

On a *craft* glove that almost peels: a light, named dust in the undercut only, blown out of the show face, can stop a vacuum pop that starts a tear. Too much powder prints as matte speckles. Unnamed drugstore talc can contaminate a later platinum recast.

Food: if a gummy ear tears, we change draft, fillet, or Shore band — we do not talc the ear. Chocolate contraction is temper, not dust.

ISO 3302-1 M2 is a drawing class, not a powder spec.

flowchart TD
  A[Undercut grab] --> B{Food cavity?}
  B -->|yes| C[No powder, no grease, no tin — change geometry or Shore band]
  B -->|craft| D{Will a 10A–20A peel without tearing?}
  D -->|no| E[Split / plug / core]
  D -->|almost| F[Named light dust in the hook only, or accept a split]
  F --> G[Blow show face clean before dump]

The photo that would prove the choice: raking light on the hook, a split option sketched, and a craft well with a *light* dust only in the undercut. A baby-powder cloud over a chocolate tray is the photo we refuse.

Typical shop values

Caption: Typical shop values.

How powder fights a later recast

Talc left in a well can inhibit or dull a new platinum face if you pour against a dusty master or a dusty old skin you were using as a pattern. Blow and wash a *craft* tool before recast. Don't "season" a food master with powder so the first pour slips — we slug-test and seal instead.

A dummy stored in a powdered undercut will pick up the dust and then reprint it. Craft only, and still blow clean.

Structure Decision beats a shaker can

Walk the geometry on paper before anyone opens talc. Flat-backed chocolate bar: open-back, no powder. Gummy ear with a mild undercut: fillet the ear, maybe 10A–20A, maybe a slightly deeper draft — still no powder. Figurine armpit that will not peel a rigid PU: plug or split. River-table edge that vacuum-locks: jacket and a vent, not mica.

A common craft sequence that *can* work: demold a green-enough PU, a puff in the hook, peel, then wash the *piece* not the well if the TDS allows. The well still gets blown clean. If you need powder every cycle, the geometry is wrong.

Food sequence we will not run: powder, dump couverture, brush off, call it 177.2600. The dust is in the article. Recast a dedicated platinum food skin if a craft well was powdered. Cabinets stay split.

Hairspray plus powder is two films. Freezing plus powder is two myths. Pins through the well plus powder is three reasons to recast.

Loaded sag 0.5–1.5 mm on a tray is a jacket/board spec. Powder will not stiffen a span.

Mixing cabinets is how powder becomes a food complaint

Operators grab the same shaker they used on a PU glove and tap it over a gummy sheet "just the ears." That sheet is retired. We recast. Don't wash-and-pray a powdered chocolate well back onto a retail line. Prototype 3–7 business days after CAD lock for the new skin. Production after the clean witness is still MOQ 20 pieces per design.

Worked example (anonymized)

PU figurine arm hook, platinum ~15A glove. Buyer talced the whole cavity; dumps came out matte. Unused spare, never powdered, was glossy and almost peeled. We CAD'd a small plug for the hook ($50), recast unpowdered, witness dump, MOQ 20. No food on the PO.

One procurement mix-up

"Non-stick" as permission to dust anything. Master release, craft dump powder, and food-cavity policy are three lines. Tooling charge is not a license to pantry-dust a 177.2600 well.

We would not recommend

We would not recommend talc, mica, starch, or baby powder in food wells.

We would not recommend powder instead of a plug on a closed letter.

We would not recommend greasing over powder to "hold it."

We would not recommend tin because a hobby kit powdered easily.

What to ask when you're buying

• Food or craft — is powder even on the table?
• Hook that needs a plug, or a vacuum pop on a near-peel?
• Named craft dust, or a drugstore jar?
• Recast plan if the show face is already dusty?
• CAD $50 if a plug is the real fix?

RFQ copy-pack

Send to [email protected] · +86 135 3006 2969 · Xinhe Blvd, Shajing, Bao'an.

RUUIPON undercut-powder RFQ Dump: food / PU / plaster / wax Photo of hook, raking light Powder already used? product if known Want plug/split quoted? yes / no Qty: witness / MOQ 20 CAD: locked / $50 3D if plug new

Matched next step: send the hook photo. We plug geometry; we dust craft hooks only when named. We will not powder chocolate. Prototype 3–7 business days after CAD lock. MOQ 20 per design.

Related: undercuts and split molds, do you need mold release, food-grade molds, contact.

Tooling charge is not unrestricted ownership of a powdered well you then ask us to bless with LFGB.

Keep the unsanded master so the recast doesn't copy dust.

FAQ

Can I use cornstarch because gummies get sanded later? Sanding sugar is post-demold. Cornstarch in the well is a film. We would not.

Will powder let me keep a one-piece glove on a rigid epoxy dump? Usually no. Epoxy doesn't shrink off. Split or plug.

Is mica "food-grade sparkle" OK in a chocolate undercut? We would not. Dry well, platinum, no tin.

Does powder change Shore readings? A dusty lip can fool a durometer. Measure a clean coupon.

If you add a plug, do I still MOQ 20 of the old one-piece? Don't multiply a geometry we would not peel. Approve the plug witness, then MOQ 20.