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Guides for buyers sourcing CNC parts in Vietnam
Written for the engineer or buyer who has a part to make and wants to know what to ask before the drawing leaves the building.
Sourcing
Finding, qualifying and working with a shop on the other side of a border.
- Sep 26, 2026
How to buy machined parts from Vietnam without running a supply chain
The three routes into Vietnam machining, what each one asks of you, the documents you need and the order of operations that keeps a first order from going wrong.
- Sep 24, 2026
Machining lead times, and the four things that actually set your date
Why a four week lead time can mean three different dates, what material availability does to a schedule, and how to plan an order so the date you are given is the date you get.
- Sep 20, 2026
Adding a second machining source without doubling your workload
How to qualify a second supplier for parts you already buy: which parts to move first, what to keep identical, how to compare fairly and what a realistic timeline looks like.
- Jul 3, 2026
Protecting your drawings when you send them to a shop overseas
Practical steps that reduce the risk of a design being copied: what to send and when, how an NDA actually helps, and the commercial habits that matter more than the paperwork.
Quoting
Getting a price you can compare, and reading the ones that come back.
- Sep 26, 2026
What machining in Vietnam actually costs, and where the saving goes
Where the cost of a machined part sits in Vietnam, which lines are genuinely cheaper than a Western shop, which are not, and the freight maths that decides if it is worth it.
- Sep 22, 2026
Minimum order quantity in machining, and why it is really a value
Why machining minimums are about order value rather than piece count, where the real floor sits once freight and setup are counted, and how to structure a small order so it is worth running.
- Sep 18, 2026
What to put in a CNC machining RFQ so you get a real quote
The eight things a machine shop needs before it can price your part, why each one moves the number, and the four mistakes that turn a quote request into a week of email.
- Sep 12, 2026
How to compare three CNC machining quotes without guessing
Two honest quotes for the same part can differ by half. Here is how to normalise them line by line, which questions close the gap and when the cheapest quote is the expensive one.
- Jul 10, 2026
What you are actually paying for in a machined part price
Machine time, setup, material, inspection and risk. Where the money goes in a CNC quote and which of those lines you can change without changing the design.
- Jul 7, 2026
How quantity changes the price of a machined part
Why the unit price falls in steps rather than smoothly, where the real break points sit and how to ask for pricing that lets you plan a year instead of an order.
Process
Milling, turning, EDM, grinding and finishing, and which one your part belongs on.
- Sep 8, 2026
3-axis, 4-axis or 5-axis: which one your part actually needs
Setups drive the price of a machined part, not the axis count on the machine. How to read your own drawing and work out which machine your geometry belongs on.
- Sep 5, 2026
Milling, turning or both: reading your part before you ask for a quote
Round parts turn, prismatic parts mill, and the interesting cases sit in between. How mill-turn, live tooling and second operations change the price of your part.
- Sep 2, 2026
When EDM is the right answer and when it is an expensive detour
Wire EDM and sinker EDM solve problems milling cannot: hardened material, sharp internal corners and deep thin features. Here is how to tell if your part needs one.
- Aug 28, 2026
Anodising, plating, passivation and blasting: picking a finish that quotes cleanly
A practical guide to the finishes shops apply to machined parts, what each one costs in days and money, and how to specify one so every quote means the same thing.
- Aug 25, 2026
When your part needs grinding and what that does to the quote
Surface, cylindrical and centreless grinding hold tolerances and finishes a mill or lathe cannot. How to tell if your drawing needs one and how to specify it.
Design
Changes to the model that take time off the machine before anyone quotes it.
- Sep 19, 2026
What a DFM review actually changes, with the numbers
Design for manufacture is a specific conversation, not a service badge. What a real review looks at, what each change is worth, and how to ask for one that is worth reading.
- Aug 21, 2026
Twelve design changes that take real money out of a machined part
Design for manufacturability for CNC parts, written as a checklist you can run against your own model before you ask anyone for a price.
- Aug 18, 2026
Wall thickness, pocket depth and corner radius: the three numbers that price your part
Three features decide how long a machined part spends on the spindle. What the practical limits are in metal and plastic, and how to design inside them.
- Aug 14, 2026
Specifying threads so they come back the way you expect
Thread callouts, engagement depth, tapping versus thread milling and when to use a threaded insert. The details that decide whether your threads are right first time.
- Aug 11, 2026
When to split a machined part into two and when to keep it whole
Machining one complex part from solid is not always cheaper than making two simple ones and joining them. How to decide, and what each route costs in tolerance.
Materials
Grades, tempers, availability and what a substitution really costs you.
- Oct 11, 2026
Carbon and alloy steels for machined parts: 1045, 4140 and 4340 compared
How 1045, 4140 and 4340 differ in strength, hardenability and machinability, which condition to buy, how to protect them from rust and what to write in an RFQ.
- Oct 7, 2026
Brass and copper grades for machined parts: C360, C260, C464 and C110 compared
How common brass and copper grades differ in machinability, conductivity and corrosion, what lead means for compliance, and how to name the grade in an RFQ.
- Jul 24, 2026
Choosing an aluminium grade: 6061, 6063, 7075 and the tempers that matter
What separates the common machining aluminium grades in strength, machinability, corrosion resistance and finish, and which ones are on the shelf in Vietnam.
- Jul 21, 2026
Choosing a stainless grade: 303, 304, 316 and 17-4 PH
How the common stainless grades differ in machinability, corrosion resistance and strength, what each one does to your machining cost and which are stocked in Vietnam.
- Jul 17, 2026
Machining plastics: what POM, nylon, PTFE and PEEK do differently
Engineering plastics machine fast and move afterwards. What to expect on tolerance, moisture, stress relief and cost, and how to specify a plastic part that comes back right.
- Jul 14, 2026
When a shop offers a different material, how to answer
Equivalent grades, local stock and certified heats. How to tell a sensible substitution from a quiet downgrade, and what to write in the request so it never becomes a dispute.
Quality
Tolerances, GD and T, inspection and proving that a part is what the drawing asked for.
- Oct 14, 2026
CMM, height gauge or optical comparator: choosing the check for each feature
What a CMM, a height gauge and an optical comparator each measure well, where they fall short, and how to name the check on a drawing so the report has meaning.
- Aug 7, 2026
How to vet a machine shop before you place the first order
The questions, documents and small tests that separate a shop which can hold your tolerance from one that will discover the problem at first article inspection.
- Aug 4, 2026
Tolerances on a machined part, explained for the person buying it
General tolerance standards, what shops hold routinely and why a blanket tight tolerance is the most expensive line on a drawing. Written for buyers, not machinists.
- Jul 31, 2026
GD and T for buyers: the four symbols that do most of the work
Datums, position, flatness and profile explained in plain language, with what each one asks the shop to do and what it adds to inspection time and cost.
- Jul 28, 2026
First article inspection: what to ask for and how to read the report
What a first article is, what belongs in the report, how to agree the acceptance rules before production and what to do when a dimension comes back out of tolerance.
Reference, not reading
The tables and templates live in the reference section: a glossary, the tolerance reference, material availability, an RFQ template and the supplier questionnaire. All free to copy.