Manufacturing knowledge · 6CProto Guides
Engineering decisions, organised
Quality, DFM & Procurement Guides
Define what the supplier must prove: a complete RFQ, controlled drawings, material records, an inspection plan and a clear acceptance decision.
Updated October 11, 2026 · 39 focused articles
Find the guide for your next decision
Follow the guide that matches the feature, failure mode or project decision you are working on.
What Is a Manufacturing RFQ?
Read the focused guide for a manufacturing rfq.
How Does Zero-Defect Quality Policy Work?
Read the focused guide for zero-defect quality policy work.
What Is a First Article Inspection (FAI) Report in Manufacturing?
Read the focused guide for a first article inspection (fai) report in manufacturing.
How can you read an MTR to avoid counterfeit metals?
Read the focused guide for you read an mtr to avoid counterfeit metals.
How can factories slash downtime when OEM spare parts are out of stock?
Read the focused guide for factories slash downtime when oem spare parts are out of stock.
Custom Metal Parts: A Procurement Manager’s Online Ordering Checklist (June 2026)
A Procurement Manager’s Online Ordering Checklist (June 2026)
Does ISO 9001 Quality Matter for Custom Manufacturing?
Read the focused guide for does iso 9001 quality matter for custom manufacturing.
What Are Secondary Operations in Manufacturing?
Read the focused guide for secondary operations in manufacturing.
How Does Global Shipping Work for Custom Manufacturing?
Read the focused guide for global shipping work for custom manufacturing.
What is Dimensional Tolerance Control?
Read the focused guide for dimensional tolerance control.
What Is Interference Checking in Manufacturing?
Read the focused guide for interference checking in manufacturing.
Advanced CMM Inspection: A Practical Framework for Custom-Part Quality Control
A Practical Framework for Custom-Part Quality Control
What Quality Documents Should You Request from a Custom Parts Supplier?
Read the focused guide for what quality documents should you request from a custom parts supplier.
What Testing and Inspection Equipment Should a Precision Parts Factory Have?
Read the focused guide for what testing and inspection equipment should a precision parts factory have.
How to Read a Manufacturing Quote: Line Items and What They Mean
Line Items and What They Mean
How to Review a Supplier DFM Report: Prioritize Changes Without Compromising Function
Prioritize Changes Without Compromising Function
GD&T Basics for Custom Parts: Flatness, Position, and Runout Explained
Flatness, Position, and Runout Explained
Units, Standards, and Drawing Callouts: Communicating Dimensions to a Manufacturer
Communicating Dimensions to a Manufacturer
RoHS, REACH, and Compliance Documents for Custom Parts: A Buyer’s Guide
A Buyer’s Guide
Packaging Custom Parts for Safe International Delivery
Read the focused guide for packaging custom parts for safe international delivery.
Importing Custom Parts to the US: HTS, Duties, and Customs Basics
HTS, Duties, and Customs Basics
Incoterms for Manufacturing Orders: EXW, FOB, and DDP Explained
EXW, FOB, and DDP Explained
How to Compare Manufacturing Quotes: Unit Price vs Total Cost
Unit Price vs Total Cost
Engineering Changes During Production: Cost, Lead Time, and How to Manage Them
Cost, Lead Time, and How to Manage Them
Tolerance Stack-Up Basics: How to Analyze Fit Before You Manufacture
How to Analyze Fit Before You Manufacture
DFM vs DFA: Design for Manufacturing and Assembly Checklists
Design for Manufacturing and Assembly Checklists
Thread Callouts on Drawings: Read Metric, UNC and NPT Correctly
Read Metric, UNC and NPT Correctly
PPAP Basics: Levels, Documents, and When Your Parts Need It
Levels, Documents, and When Your Parts Need It
Hardness Testing for Metal Parts: Rockwell vs Brinell vs Vickers
Rockwell vs Brinell vs Vickers
Thread Inspection: Pitch Diameter, Go/No-Go Gages, and Reporting
Pitch Diameter, Go/No-Go Gages, and Reporting
Sealed Enclosure Design: Gasket Grooves, Wall Thickness and IP Testing
Gasket Grooves, Wall Thickness and IP Testing
CMM Inspection: Ensuring Precision in Custom Parts, Prototypes, and High-Volume Manufacturing
Ensuring Precision in Custom Parts, Prototypes, and High-Volume Manufacturing
CAD File Compatibility: Ensuring Your Design Integrates Smoothly with Rapid Prototyping and Custom Manufacturing
Ensuring Your Design Integrates Smoothly with Rapid Prototyping and Custom Manufacturing
Lead Time Management: Delivering Fast, Reliable Delivery for Rapid Prototyping and Custom Manufacturing
Delivering Fast, Reliable Delivery for Rapid Prototyping and Custom Manufacturing
Dimensional Stability: Preserving Accuracy From Prototype to Production
Preserving Accuracy From Prototype to Production
How to Protect Your Design IP When Ordering Prototypes from Overseas
Read the focused guide for protect your design ip when ordering prototypes from overseas.
How to Collaborate with a Manufacturing Partner Across Time Zones
Read the focused guide for collaborate with a manufacturing partner across time zones.
Quality Control for Low-Volume Production: Sampling, FAI, and Traceability
Sampling, FAI, and Traceability
Working with a Chinese Manufacturing Partner: RFQ, Samples, and Payment Terms
RFQ, Samples, and Payment Terms
Before you release the project
- Define the function, environment and the question this batch must answer.
- Specify material grade, geometry, quantity, finish and the dimensions that control fit.
- Agree the inspection method and the evidence required to accept the parts.
- Record the drawing revision and approval before production begins.
Common planning questions
What makes an RFQ ready to send?
A consistent CAD model and revision-controlled drawing, material grade, quantity, finish, acceptance criteria and required records give the supplier a defined basis for quotation.
Does certification replace part inspection?
No. Quality-system certification describes management controls. The parts still need an agreed inspection and acceptance plan.
Move from guidance to a reviewed project
Send the CAD model and drawing with material, quantity, finish and inspection requirements. Use the relevant service page to review the available manufacturing route.