Precision Injection Molding Service from a Trusted China Manufacturer

We mold tight-tolerance plastic parts that fit and work the first time. As a China precision injection molding manufacturer and supplier, our factory holds tolerances down to ±0.01 mm. Upload your CAD file and get a factory-direct quote with free DFM feedback within 24 hours.

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ISO 9001 Certified Factory Quote in 24 Hours NDA Protected Free DFM Feedback

The Problem We Solve

Why Buying Precision Parts Goes Wrong

These are the problems buyers tell us about every week. Here is how we take each one off your desk.

Parts Come Out of Tolerance

A few microns off and your assembly will not fit. We hold ±0.01 mm as standard and measure every critical dimension with CMM before shipping.

Warping, Sink Marks, Short Shots

Bad tooling and wrong process settings cause defects. Our engineers balance the mold, lock in the process window, and fix issues at T1.

Deadlines Keep Slipping

Late parts delay your launch and cost you sales. We confirm a firm timeline with your quote and update you at every stage.

Hidden Costs After Ordering

Cheap quotes often grow after you pay. Our quote is itemized and final, with no surprise charges for tooling, setup, or packing.

Slow Replies and Confusion

Weeks of silence and unclear answers waste your time. You get one dedicated engineer who replies within hours.

Worried About Your Design

Sending files to a new supplier feels risky. We sign an NDA before you share anything, and your design and mold stay yours.

Precision Injection Molding at YiguProto China factory
Design review, tooling, molding, and inspection under one roof at our Dongguan, China factory

Our Solution

One China Manufacturer, One Accountable Partner

YiguProto is a precision injection molding company based in Dongguan, China. We own our tool shop, molding floor, and quality lab. That means no middleman, no markup, and no finger-pointing.

From your first CAD file to the last shipped carton, one team handles design review, tooling, molding, inspection, and delivery. You always know who to call.

  • Free DFM review on every quote
  • Tolerances to ±0.01 mm as standard
  • ISO 9001:2015 certified factory
  • Inspection report (FAI / CMM) with each order
  • You own the mold, with free storage and maintenance
  • English-speaking engineers, replies within hours
Upload Your File & Get a Quote Ask an Engineer

Overview

What Is Precision Injection Molding?

In plain words: we melt plastic pellets, push the molten plastic into a steel mold, let it cool, and eject a finished part. Precision molding means the part stays accurate to a few microns, again and again.

Standard injection molding is fine for everyday parts. Precision injection molding is for parts where small size changes break the product, such as medical devices, electrical connectors, gears, and optical parts.

To hit these numbers, three things must be right: the mold, the machine, and the process. Our tool shop cuts the cavity to within microns. We run 60T to 350T precision presses with closed-loop control. And our engineers lock in the process window before production starts.

What precision molding gives you:

  • Repeatable dimensions, part after part
  • Low per-part cost at medium to high volume
  • Wide choice of engineering-grade plastics
  • Complex shapes with inserts, threads, and undercuts
  • Surface finishes from mirror gloss to matte texture

When to Choose Precision Molding

Good fit if you need:

  • ✓ Tight tolerance, ±0.01 mm or better
  • ✓ Small parts, some under 1 gram
  • ✓ Medical, electronics, auto, or optical use
  • ✓ Volume where every part must match

Consider another process if:

  • ✗ You need fewer than 50 parts
  • ✗ Your design still changes every week
  • ✗ You need parts in less than 5 days

Capabilities

Precision Injection Molding Capabilities at a Glance

Real numbers, so you can plan your project with confidence.

±0.01

Tolerance

±0.01 mm as standard. Down to ±0.005 mm on critical features.

60T

Press Tonnage

60T to 350T precision presses with closed-loop process control.

2 kg

Part Size & Weight

Up to 500 × 400 × 300 mm. From 0.1 g to about 2,000 g.

100+

Materials

ABS, PC, PA, POM, PEEK, PPS, PBT, and TPE / TPU elastomers.

1-32

Cavities

Single-cavity, multi-cavity (2 to 32), and family molds.

500k

Mold Life

Aluminum: 1,000 to 5,000 shots. P20 steel: 50,000+. H13 / S136: 500,000+.

SPI

Surface Finish

SPI A1 to D3, VDI / MoldTech texture, polishing, and painting.

10d

Lead Time

T1 samples in 10 to 15 days. Production in 5 to 10 days after approval.

Our Solutions

Precision Molding Solutions for Every Stage

From one prototype to millions of parts, we have a solution that fits your project and your budget.

Rapid Tooling & Prototype Molding

Lead time: 10 to 15 days  |  Volume: 50 to 5,000

Aluminum molds cut fast and cost less. You get real molded parts in production material for testing, not 3D prints.

Production Steel Tooling

Lead time: 15 to 30 days  |  Volume: 1,000 to 500,000+

Hardened P20, H13, and S136 steel molds built for long life. Multi-cavity and hot runner options cut cost per part.

Micro & Tight-Tolerance Molding

Lead time: 20 to 30 days  |  Parts under 1 g

Small parts with features down to 0.1 mm. Ideal for connectors, gears, and medical micro-components.

Insert & Over Molding

Lead time: 15 to 25 days  |  Multi-material parts

Mold plastic around brass inserts, or bond a soft TPE / TPU layer over a rigid base for grips and seals.

2K (Two-Shot) Molding

Lead time: 20 to 30 days  |  Two colors or materials

Mold two materials or colors in one cycle. Fewer assembly steps, stronger parts, and a cleaner look.

Optical & Transparent Molding

Lead time: 20 to 30 days  |  Clear, cosmetic parts

PC and PMMA parts with high clarity and no flow marks. For lenses, light guides, and display covers.

Materials

100+ Materials for Precision Molding

We stock common and engineering-grade resins. Need a special grade? Just ask and we will source it.

Commodity Plastics

  • ABS — tough and low cost
  • PP — flexible, chemical resistant
  • PE (HDPE / LDPE) — impact resistant
  • PS / HIPS — rigid, low cost
  • PVC — rigid or flexible

Engineering Plastics

  • PC — clear, impact resistant
  • PA6 / PA66 — strong, wear resistant
  • POM — low friction, rigid
  • PMMA — optical clarity
  • PBT / PET — good for connectors

High-Performance Plastics

  • PEEK — heat and chemical resistant
  • PPS — high heat, chemical resistant
  • PEI (ULTEM) — flame retardant, strong
  • PSU / PPSU — steam sterilizable
  • PTFE — ultra-low friction

Elastomers & Flexible

  • TPE — soft touch, Shore 20A to 95A
  • TPU — abrasion resistant
  • LSR — silicone, medical / food grade
  • EVA — soft and lightweight
  • TPEE — flexible, fatigue resistant

Glass-filled, UV-stabilized, flame-retardant (UL94 V-0), and food-grade grades available. Custom Pantone / RAL color matching on production orders.

Quality Control

How We Keep Every Part in Spec

Precision is a process, not a promise. Here is how we control it at every step.

Incoming Material Check

Every resin lot is checked against the datasheet. Off-spec or wrong material never reaches the press.

Mold Steel Verification

We verify steel grade and hardness before cutting. A weak mold cannot hold tight tolerance for long.

In-Process Monitoring

Press parameters are monitored every cycle. Closed-loop control keeps dimensions stable run after run.

CMM & Measurement

Critical dimensions are measured with CMM, projectors, and gauges. Data is recorded, not guessed.

FAI & Inspection Report

First article inspection and a full dimension report ship with your order on request.

Cosmetic & Function Check

We check appearance, fit, and function before packing. Defects are caught here, not on your line.

Surface Finishes

Parts That Look as Good as They Fit

Pick the finish that matches your product's look, feel, and function.

SPI-A (Glossy)

Diamond-buffed, mirror-like surface (A1 to A3). For lenses and cosmetic parts.

SPI-B (Semi-Gloss)

Fine sanded surface (B1 to B3). Smooth with low shine. Common on industrial parts.

SPI-C (Matte)

Stone-ground matte finish (C1 to C3). Hides tool marks and small defects.

SPI-D (Textured)

Dry-blast texture (D1 to D3). Good for grips and hiding ejector marks.

MoldTech / VDI Texture

Etched leather grain and geometric patterns, from fine to coarse.

Polishing & Coating

Mirror polishing, painting, pad printing, laser engraving, and UV coating.

Industries

Trusted Across Precision-Critical Industries

Our precision parts end up in products used around the world every day.

Medical & Dental

Device housings, surgical handles, and fluid parts in medical-grade PC, PEI, and LSR.

Automotive

Sensors, connectors, and trim in glass-filled PA and PP that hold tight tolerance.

Electronics

Enclosures, connectors, and bezels in PC / ABS, PBT, and PA.

Aerospace

Lightweight brackets and housings in high-performance engineering resins.

Consumer Goods

Appliance parts, houseware, and packaging in ABS, PP, and PMMA.

Industrial

Gears, bushings, and valve bodies in POM, PA, PEEK, and PPS.

How It Works

From CAD File to Finished Parts in 6 Steps

A clear, proven process with no surprises. You always know where your project stands.

1

Upload Your Design

Send your 3D CAD file (STEP, STP, IGES, or X_T) with your material, quantity, and finish needs.

2

Get Quote & Free DFM

Within 24 hours you get an itemized quote plus a DFM report that flags issues and suggests fixes.

3

Approve & Pay

Review the quote, ask questions, and request changes. Once approved, we start cutting steel.

4

Mold Making & T1 Samples

We build the mold in-house, run T1 shots, inspect them, and send sample photos and parts for approval.

5

Production Run

After you approve T1 samples, we run full production and inspect every batch for dimensions and function.

6

Pack & Ship

Parts are packed for safe transport and shipped with your preferred carrier, tracked to your door.

Start Your Project Today

Design Tips

Simple Design Rules That Cut Cost and Defects

Good design for manufacturing (DFM) lowers cost, reduces defects, and speeds up delivery. Here are the basics.

Keep Walls Even

Aim for 1.5 to 3.0 mm and keep thickness uniform. Uneven walls cause sink marks and warpage.

Add Draft Angles

Use 1° to 2° on vertical walls and 3° to 5° on textured surfaces, so parts eject cleanly.

Round Your Corners

Use inside radii of at least 0.5 mm. Sharp corners trap stress and weaken the part.

Size Ribs Right

Make ribs 40 to 60 percent of wall thickness and add draft. Thick ribs sink on the other side.

Control Bosses

Keep boss walls at about 60 percent of the main wall, and tie them to ribs or walls.

Plan the Gate

Place gates on non-cosmetic surfaces. Good gate location avoids weld lines and flow marks.

Not sure your design is ready? Send it to our engineers for a free review.

Why YiguProto

Six Reasons Buyers Choose Our China Precision Molding Factory

We are not a trading company. We are the manufacturer. Here is what that means for you.

Fast Quotes, Fast Turnaround

Send your 3D files and get a detailed quote with DFM feedback within 24 hours. T1 samples in as little as 10 business days.

Factory-Direct Pricing

No trading company and no hidden markup. You work directly with the supplier that owns the machines and the tool shop.

Quality You Can Measure

ISO 9001:2015 certified. Every batch is inspected, and FAI and CMM reports are available on request.

Engineering Support in English

Every project gets one dedicated engineer who reviews your design and replies within hours.

100+ Materials, Custom Colors

From ABS to PEEK, plus Pantone / RAL color matching and special grades for heat, UV, and flame resistance.

Your IP Is Protected

We sign an NDA before you share files. Your design stays private and your mold is 100 percent yours.

See for Yourself — Get a Quote

Trusted Worldwide

Companies Around the World Rely on Our Precision Molding Service

"We moved our tooling to YiguProto and the difference was clear. DFM feedback was spot on, T1 samples were nearly perfect, and production ran smoothly. Communication was fast the whole way."

— Procurement Manager, U.S. consumer electronics company

"As a startup we needed a supplier who could do low-volume runs without killing us on tooling cost. Their rapid tooling option let us test in real material before committing to production."

— Founder, European hardware startup

"The quality reports they send before shipment give us confidence. We have worked with them for over three years across many projects, and they deliver on spec and on time."

— Engineering Director, Australian industrial equipment maker

12+
Years in Manufacturing
3,000+
Molds Built
50+
Countries Served
ISO 9001
Certified Factory

FAQ

Precision Injection Molding — Frequently Asked Questions

Answers to the questions buyers ask us most often.

Precision injection molding makes plastic parts that stay accurate to a few microns, part after part. Standard molding is fine for everyday parts. Precision molding is for parts where tiny size changes break the product, such as medical devices, connectors, gears, and optical parts.
Our standard tolerance is ±0.01 mm on most features. For critical dimensions we can hold down to ±0.005 mm. Tell us your key dimensions and we will confirm feasibility during the free DFM review.
Upload your 3D CAD files and tell us your material, quantity, and finish needs. Most quotes come back within a few hours on business days, and never more than 24 hours. Every quote includes free DFM feedback.
We prefer STEP (.stp, .step) or IGES (.igs, .iges) files for clean geometry. We also accept SolidWorks, Inventor, Creo/ProE, Parasolid (.x_t), and STL files. 2D PDF or DWG drawings are welcome for tolerances and notes.
There is no strict MOQ. We support prototype runs as low as 50 pieces with rapid aluminum tooling. For production steel tooling, typical starting quantities are 500 to 1,000 pieces, and we stay flexible.
For rapid aluminum tooling, T1 samples are ready in 10 to 15 business days. For production steel tooling, T1 takes 15 to 25 business days. After you approve T1 samples, production runs take about 5 to 10 business days. We give you a specific timeline with your quote.
Mold cost depends on part size, complexity, number of cavities, mold material, and surface finish. Small prototype aluminum molds often start around $1,000 to $3,000. Complex production steel molds can range from $5,000 to $50,000 or more. Send your CAD file for an accurate quote.
Yes. All customer files, designs, and project details are kept strictly confidential. We are happy to sign your NDA before you share sensitive information, and we never share or display customer parts without permission.
Yes. Every quote includes a free DFM review. Our engineers check wall thickness, draft angles, undercuts, gate location, sink marks, weld lines, and ejector placement, then suggest changes that cut cost or reduce defects.
You own the mold 100%. The tooling price covers the full cost of building it. We store and maintain it free at our factory while you run production with us, and we ship it to you if you ever move production.
Yes. For low volumes of 50 to 5,000 parts we use aluminum molds that cut fast and cost less. For medium to high volumes of 1,000 to 500,000 or more parts, we build hardened steel molds that last for hundreds of thousands of shots.
Yes. We match Pantone, RAL, or your custom color standard, and we stock glass-filled, UV-stabilized, flame-retardant (UL94 V-0), and food-grade resins. Color chips can be provided for approval before production.

Ready to Get Your Precision Parts Made?

Upload your CAD file today and get a factory-direct quote with free DFM feedback within 24 hours. No obligation. No middleman. Just tight-tolerance parts from a China manufacturer you can trust.

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