STEP vs STL vs IGES for an RTV Mold Quote | RUUIPON

A quote file is a geometry contract, not a folder of whatever exported. STEP/STP in millimetres is the engineering file we can draft, split, and shrink (platinum about 0.1–0.3%) against. STL is a mesh: fine for a sculpted mascot if units are named and the shell is watertight; bad for a logo that still needs millimetre strokes. IGES/IGS can carry surfaces; it also arrives as trimmed-face soup we have to heal. This page is the format matrix — which attachment actually prices a custom RTV tool — not a general “send anything” packing list.

RUUIPON, Bao'an since 2018. USD $50 when CAD scope applies because the file is not pour-ready. Prototype 3–7 business days after CAD lock. MOQ 20 pieces per design. Steel/LSR *part* files go to wydsilicone.com.

Does not apply when you already have a locked STEP from a previous PO and only need a recast (send the job number), when the attachment is a PDF of a listing, or when units are “whatever the printer used.” We will not freeze mm from that.

What each format is good for on this floor

STEP / STP. Solids, millimetres, watertight. We can put a shut on it, offset for shrink, and mark logo depth. Usually skips the $50 line. Still need dump, Shore, grams or volume, qty. A STEP of a figurine with no shut is a solid, not a mold.

STL. Triangles. Ask: millimetres or inches? Watertight? Positive (the dump) vs negative (the cavity) named? Sculptural masters yes; precision holes and logo strokes often need a rebuild. $50 if we repair mesh or add split. A 0.05 mm STL chord on a serif is not a millimetre lock.

IGES / IGS. Older CAD exchange. Can be perfect surfaces; can be gaps. We open it, we say heal vs native STEP. Do not send both IGES and STEP of different revs without saying which wins.

OBJ / 3MF / native SolidWorks only. Ask first. We would rather you export STEP.

Photos. Not a CAD format. Ruler in-plane plus one named size starts an RFQ; $50 builds the model. A coin is not a datum.

ISO 3302-1 M2 on a 2D does not replace any of these. Class is not a solid.

The photo that would prove a format call: file open in CAD with units visible, one measured length matching a caliper on the real part, rev in the filename.

Typical shop values

Caption: Typical shop values.

Worked example (anonymized)

A jewelry client sent IGES of a pendant and STL of the same object at 98% scale. Revs disagreed by a millimetre on the bail. We stopped. They exported one STEP in mm, confirmed a 28 mm overall with calipers. No $50. Lock, 3–7 business days, first wax witness, MOQ 20. The IGES was not “wrong”; it was not the winner until they said so.

Units, rev, and shrink — three silent stacks

Open every mesh in millimetres and confirm one overall with a caliper photo. Inches-as-mm is a 25.4× brick we will not pour “to see.” Printers that export 98% “for shrink” stack on our platinum 0.1–0.3% and you will argue grams. Write scale 1:1 unless we agreed a compensation on the master.

Rev in the filename beats “latest” in a chat. If IGES_v3 and STEP_v2 both arrive, production follows the lock screenshot, not the zip mtime. We would not chase WeChat images of a screen as a rev.

A 2D PDF with balloons is a friend of STEP, not a replacement. Use it for logo depth, class (ISO 3302-1 M2 if you insist on a rubber class on the dump), and CTQs. Do not balloon an STL screenshot and call it a drawing.

Food-contact dumps still need platinum and a document path (21 CFR 177.2600 / LFGB as specified). Format choice does not pick chemistry. A beautiful IGES of a chocolate bar on tin-cure is still a food-path conversation we would not spec as tin.

If the only file you have is a broken STL, pay the $50 when that scope applies and we rebuild a solid you can mark. Fighting a non-manifold mascot for a week is not fifty dollars — we will say reconstruction vs simple 3D before we charge.

One procurement mix-up

“3D file attached” is not a format. Name STEP, STL, or IGES, units, and rev. Tooling charge ≠ a license to keep emailing a new STL after lock without an ECO. Ownership of the CAD is a PO sentence.

Native SolidWorks, Fusion, and Rhino files are a courtesy if we already agreed. Export STEP anyway so the archive is not a seat-license lottery next year. Archive is not ownership; write who holds the solid after lock.

We would not recommend

We would not recommend quoting from a PDF render.

We would not recommend STL inches opened as millimetres.

We would not recommend two formats of two revs in one zip without a winner.

We would not recommend an unscaled photo pack to skip STEP and skip the $50 line.

flowchart TD
  A[File for RTV quote] --> B{Format?}
  B -->|STEP mm watertight| C[Price master — usually skip $50]
  B -->|STL| D{Units + watertight + pos/neg?}
  D -->|Yes sculptural| E[Price — $50 if we repair or split]
  D -->|No| F[Stop — confirm units or rebuild]
  B -->|IGES| G[Open and heal — say which rev wins]
  B -->|Photo / PDF| H[Datum or style talk — $50 to model]
  C --> I[Lock then 3–7 business days]
  E --> I
  G --> I
  H --> I

Zip the winning file only. Loose OBJ plus textures plus a blender project is not an RTV quote pack; it is a render pack. We will ask you to export a millimetre STEP or a named STL again today.

What to ask when you're buying

• Will you open my IGES, or should I export STEP?
• If the STL is inches, will you catch it before pour?
• Who owns the rebuilt STEP if I paid $50?
• Recast next year: which format sits in the archive?
• Dump, Shore, qty — the file is not the whole RFQ.

RFQ copy-pack

[email protected] · +86 135 3006 2969 · Xinhe Blvd, Shajing, Baoan.

RUUIPON file-format RFQ Format: STEP / STL / IGES / photos Units: mm (confirm one overall) Rev / filename Positive vs negative named Dump / Shore / grams Qty: sample / MOQ 20 CAD: file is lock-ready / need $50 3D

Matched next step: send one winning file in millimetres plus dump notes. We will say heal, skip $50, or remodel. Prototype 3–7 business days after CAD lock. MOQ 20 per design.

Related: what files for a custom mold quote, mold from photos, custom mold quote, contact.

FAQ

Is STL good enough for a logo bar? Usually no. Logo strokes want millimetres in a solid. STL is a sculpt tool. Send vectors plus STEP, or $50 to build the pocket.

Should I convert IGES to STL to “make it easier”? No. You throw surfaces away. Export STEP.

Can you quote from a 3MF from a consumer printer? Ask first. Many 3MF files are printer-ready, not mold-ready, and scale is a trap.

If STEP and STL disagree, which do you pour? Neither until you name the winner. We will not average them.

Does a clean STEP skip MOQ 20? No. File quality skips some CAD fee. Production is still MOQ 20 pieces per design.