Spare Molds: Recast Skin vs Rotation Qty | RUUIPON

Spare capacity on a custom RTV program is not “order a few extra floppy trays.” You either recast the skin against a living master, you buy a spare jacket that still keys, or you purchase rotation quantity so one SKU is never down while a lip is torn. Those three are different lines. A spare skin that does not fit last month’s jacket is scrap. A spare jacket with no master left in archive cannot be recast when the rubber dies. Production lots are still MOQ 20 pieces per design. Prototype of a new revision is 3–7 business days after CAD lock. Simple 3D is USD $50 when that CAD scope applies.

Steel/LSR *part* spares (cavity inserts, cold-runner drops) are a WYD conversation: wydsilicone.com.

Does not apply when you have not locked a master yet (you need a sample, not a spare), when the CAD is still moving, or when you want us to keep twenty unlabelled leftovers from another customer as your buffer. We will not do that.

Recast, spare jacket, rotation — pick the failure you are insuring

Recast the skin. The master still lives, the jacket still keys, the lip tore or the logo washed. We pour a new platinum face, vacuum, pull, and you slot it back. This is the cheap restore if archive terms were written. It is impossible if the master was sanded “to clean it,” thrown out, or never yours.

Spare jacket / mother mold. The rigid support is what registers keys and stops 0.5–1.5 mm sag. Jackets chip, warp, and get lost. A second jacket lets you run while the first is repaired. Buying two skins and one warped jacket does not give you two tools.

Rotation quantity. Extra complete tools (skin + matching jacket) so you can rest a tray, wash, and swap. Useful when dumps/month would wear one lip before a recast can ship from Bao’an. Two 8-up trays often beat one 16-up for this reason: a torn 16 parks the SKU.

Paying a tooling charge does not, by itself, mean we must keep a shop copy forever. Write archive duration and who owns the master.

The photo that would prove a spare program is the master tagged with a revision letter, two jackets with matching key paint, and a torn skin next to its recast. A pile of extra trays in a tote is not that photo.

Typical shop values

Caption: typical shop values, not a named PO.

Common mix-up: extra rubber without matching keys

Buyers add “+4 spare molds” to a PO and receive four skins that do not register on the production jacket. Or they store tin-cure leftovers for a season and the cavities shrink. Or they sand the master after a bad dump and then ask for a recast of the original logo. Spare means *interchangeable with the tool you already qualified*. ISO 3302-1 M2 on the drawing will not make two jackets from different years mate.

Worked example (anonymized)

A pectin line ran one 18-up tray hard, about 2,000 dumps a month. The outer lip tore in week six. They had no master terms and no second jacket. We could not recast until they shipped the torn skin and we rebuilt a master from a scan — extra time, extra CAD. On the reorder they bought MOQ 20 of the skin, kept the CNC master in archive, and added one spare jacket. Rotation was two trays on the bench, one resting. That is the spare program we wanted on the first PI.

We would not recommend

We would not recommend stocking loose 10A skins without jackets “because silicone is cheap.”

We would not recommend tin-cure as a spare that will sit on a shelf. Platinum holds size better (about 0.1–0.3% then stable); tin keeps moving.

We would not recommend one 24-up with no spare when that sheet is the only way you hit grams. Split into two smaller trays if downtime is the real cost.

flowchart TD
  A[Need spare capacity] --> B{Master still alive and unsanded?}
  B -->|no| C[You do not have a recast path — rebuild, then archive]
  B -->|yes| D{What failed?}
  D -->|torn lip / washed logo| E[Recast the skin]
  D -->|warped or lost jacket| F[Spare jacket that still keys]
  D -->|SKU cannot stop| G[Rotation qty: complete tools]
  E --> H[Same revision letter]
  F --> H
  G --> H

What to ask when you are buying spares

• Will you keep the unsanded master, and for how long?
• Is a spare a skin, a jacket, or a complete tool?
• Do keys match across the lot — same revision letter?
• If I rotate two 8-ups, is that one design (MOQ 20 of that 8-up) or two?
• Who pays for a recast after wear versus after I change the logo?

Related: MOQ 20 per design, cavity count vs grams, contact. Gummy trays that already run hard can start from custom gummy molds.

RFQ copy-pack — recast vs rotation

Paste into [email protected]:

Existing revision letter / or new CAD Dumps per month and what usually fails (lip / logo / jacket / sag) Need: recast skin / spare jacket / rotation of complete tools Master: we keep it / you archive it / not sure Same keys across the lot: required Pour + food-contact path: 177.2600 / LFGB / craft-only If new design: prototype 3–7 days after CAD lock, then MOQ 20 per design Do not ship unmatched skins

Send the revision letter and what actually fails. We will say recast versus rotation — not a tote of extra rubber. Phone +86 135 3006 2969. Licheng Technology Industry Park, Xinhe Blvd, Shajing, Bao’an, since 2018.

How we would size rotation (method, not a result)

You do not need a magic “spare factor.” You need downtime you can survive.

If recast transit is longer than you can be down, you buy rotation, not hope. CBD/THC tooling follows the same spare logic — tools only, no dosing claims.

FAQ

Can I buy four extra skins now and jackets later? Only if we still have the key CAD and the jacket design. Safer to buy complete tools or a defined spare jacket on the same revision.

Is a recast cheaper than a new mold? Usually, if the master is unsanded and the jacket still keys. A logo change is a new face, sometimes a new design (another 20 if it goes to production).

Do spares count toward MOQ 20? Spares of the *same* locked design sit inside that lot or a reorder of it. A different cavity is a different twenty.

Should I keep tin-cure extras on a shelf for a year? We would not. Tin keeps shrinking in storage. Platinum is the spare we would actually warehouse.

If I paid tooling, must you recast forever? No. Archive duration and ownership are PO terms. A tooling charge is not unrestricted, perpetual recast rights.