How to Audit a Custom RTV Silicone Mold Factory

This page is not a claim that only direct factories are good. A trader can be competent. If you're auditing a custom RTV mold supplier, your job is to see who controls engineering, the pour, the documents, and the recast. Look for a mix bench, vacuum, masters, and a jacket table — not a stock photo of an LSR press. RUUIPON is a Bao'an workshop (since 2018, Licheng Technology Industry Park). You can visit by appointment, match the payment entity to the door, and watch A/B weighed.

We sell RTV cavities. If the showroom is full of compression presses and cold-runners, you may be in a parts plant (a high-volume parts plant). That's a valid factory for *parts*, the wrong evidence for a pectin tray.

A one-pass RTV audit you can actually run

1. Legal and money

Chinese legal name on the contract, invoice, and bank account match.
Address is a workshop you can walk, not only a showroom in another district.
Export docs (if you need them) use that same entity.

2. Process evidence (live or video)

Master making or receiving: CNC, print post-cure, sample copy.
A/B scale, mix ratio posted (1:1 or 10:1 by grade), vacuum chamber that gets used.
Mold boxes, keys, cores, jackets — hardware, not a slide.
A real dump test, not only a pretty unused cavity.

3. Engineering

Someone can mark a split on *your* screenshot in the meeting.
They can say open-back vs two-part vs core vs jacket using a structure rule, not "we can make any mold."
They will say no.

4. Sample and change control

Written prototype pass/fail. Golden sample ID. Reorder cites it.
Compound changes need your signature.

5. Documents

Food pack is compound/lot, 21 CFR 177.2600 extraction and/or LFGB as named — not "FDA factory."
ISO 9001 if they have it is a QMS certificate, not a substitute for the compound file.

Traders: ask who pours, whether you may visit *that* shop, and who owns the master when the trader changes subcontractors.

Common mix-up: machines in the photo aren't the quoted process

LSR injection cells, two-roll mills, and flash presses prove a parts capability. They do not prove an RTV pour cell. The reverse is also true: a vacuum chamber does not mean they can run your 50,000-pc gasket. Match the machine to the object on the PI.

Typical shop values (what a serious RTV shop can state without theatre)

Item	Typical shop value
Mix	Platinum 1:1 or 10:1; vacuum until foam collapses
Cavity Shore they can defend	10A–20A with jacket when loaded
Prototype	3–7 days after CAD lock
MOQ	20 molds per design after approval
Shrink they should not mix up	RTV platinum ~0.1–0.3%; HCR ~1.5–2.5%; LSR ~2–3%
Food claim	Compound report, not a gate sticker

Reference values only. Confirm material-specific limits against the supplier’s technical data and agree project acceptance criteria before production.

Failure: you paid a website, the pour happened somewhere else

Symptom: Sales cannot name the grade; workshop video is stock; payment name ≠ contract name; sample approved, production Shore different; nobody knows who has the master.

Confirm: Video call into the mix bench with your PO number on a card. Match business license, invoice, and warehouse. Ask for the recast path in writing.

Fix: Don't place the production PO until entity + process + golden sample line up. A cheaper trader who can show the pour cell and the change-control file may still be the right buy.

Worked example: two-hour Bao'an walk

A US buyer spent two hours at Licheng Technology Industry Park: license photo, mix bench with 10:1 platinum on the scale, vacuum lid scarred from real use, a jacketed 12-up tray, and the Rev B golden-sample card. They skipped the pretty press room that belonged to a parts conversation. We would not have used that press room as RTV evidence, and we would not have asked them to treat a WeChat catalog as an audit.

What to ask when you're buying (take this onto the floor)

Show me the vacuum and the last mold box you poured, not a brochure.
Who weighs A/B on my job, and at what ratio?
Who marks the split, and will they say this geometry should not be one-piece?
What is the payment legal name vs the workshop name?
Where does my master sleep, and what happens if I recast in 18 months?

When this page is the wrong route

If you need an LSR/HCR parts audit (press tonnage, cold-runner, mill room), use a parts checklist as an HTV product RFQ here, or ask us for a high-volume LSR tool — this RTV list will miss the real risks. A one-off craft artist selling three glove molds doesn't need a seven-section audit. Geometry still overrides: a hollow concrete jacket deserves a walk of cores and shells even if the supplier is small.

RFQ: audit pack before the first PO

Copy this.

Legal entity name, address, payment beneficiary
Quoted process: RTV pour (ban silent HCR/LSR substitution)
Live video or visit of mix / degas / pour
Named engineer for DFM
Material grade + document list
Sample approval method and reorder change control
Tooling/master ownership terms

Send the drawing and ask for a workshop clip of mix, degas, and pour plus the legal name on the PI. If those don't match, you're not done auditing. [email protected] · +86 135 3006 2969.

We would not recommend paying a different English brand name than the one on the workshop lease. We would not recommend skipping master-custody language because "they're a factory." We would not recommend disqualifying a trader who can show the real pour cell and contract it.

RUUIPON Mold Structure Decision:

Quoted object is an RTV cavity? - yes -> See mix, vacuum, master, jacket
See mix, vacuum, master, jacket -> Entity matches invoice
Entity matches invoice -> Can they mark open-back vs split vs core vs jacket?
Can they mark open-back vs split vs core vs jacket? - no -> Don't PO yet
Can they mark open-back vs split vs core vs jacket? - yes -> Prototype written pass/fail, then MOQ

Production stays at MOQ 20 pieces per design. Custom/simple 3D modeling is USD 50 when that scope applies. Prototypes are commonly 3-7 business days after CAD lock.

FAQ

Is a trading company automatically a red flag? No. The flag is when nobody can show the pour or the master custody. A transparent trader plus a real workshop can be a stable supply chain.

What's the fastest remote audit? A live call into the mix bench and the master rack, license on camera, and a DFM mark-up of your file the same day.

Do you allow third-party inspectors? Yes by arrangement. Give them this checklist so they don't audit an LSR press on an RTV PO.

Does ISO 9001 mean the molds are food-safe? No. ISO is a management system. Food is the compound pack you named.

Can I visit Bao'an? Yes, by appointment. Licheng Technology Industry Park. Bring the drawing you actually want to buy.