What working with a CNC subcontractor looks like, step by step

The first machining order placed externally often looks like a black box: you send a drawing, after some time an offer arrives, then a package with parts. What happens in between — nobody knows. Yet it is exactly this "in between" that decides whether you get good parts on time. A well-organised collaboration with a CNC subcontractor is a predictable sequence of stages in which both sides know who needs what and when.

In this post we lay out the whole path: from inquiry, through NDA and quoting, to delivery and invoicing. For each stage we show what happens on the supplier's side — because that explains why some gaps in an inquiry cost days while others hurt nobody.

Working with a CNC subcontractor — seven stages

The whole path from idea to invoice looks like this:

1. Request for quotation with the part documentation.
2. NDA — if the documentation is confidential.
3. Quotation — at Nomatec, as standard, within 48 hours.
4. Order and confirmation of the delivery date.
5. Production: process planning, programming, machining and dimensional inspection.
6. Delivery or collection of the parts.
7. Invoicing and arrangements for the next orders.

How long does it all take? With complete documentation and a typical part, the whole path from inquiry to delivery closes, as a rough guide, in two to four weeks, of which the machining itself is usually the smaller part — the rest is consumed by decisions, material and the production queue. Below, each stage up close.

Inquiry, NDA and quotation

The inquiry is the foundation of everything else. The complete package is a PDF drawing with tolerances, a STEP model, the material, the quantity, the required finish and the deadline — we break this down in detail in what files to send for a CNC quote. The fewer assumptions the supplier has to make, the faster and more accurate the offer.

If the part is covered by design confidentiality, an NDA is signed before the drawings are sent. This is normal practice and usually takes one day — provided the template is ready rather than written from scratch. For typical machine parts, most customers skip this step.

Once the complete package arrives, work begins on the supplier's side that the customer does not see: the process engineer analyses the drawing and plans the operations, checks material availability and price, estimates machine times, the number of setups and the cost of special tooling. If the geometry raises doubts or the tolerances are inconsistent, they come back with questions — and this is the moment where incomplete inquiries lose the most time. With complete data, the offer goes out within 48 hours: price, lead time and any process remarks.

Good practice at this stage: if you are planning a batch, ask right away for a variant quote — for example for 1, 10 and 50 pieces. The production setup cost is spread across the batch, so the differences can be large, and a variant offer lets you decide on the order size without a second quoting round.

Order and production

After the offer is accepted, the customer places the order and the supplier confirms the date — from that moment both sides have binding arrangements. It is worth repeating the drawing number and revision in the order to rule out work on an outdated version of the documentation.

On the supplier's side, production preparation starts. Material is ordered or drawn from stock, and the CAD/CAM programmer prepares the machining program and selects the tools. For new parts, the standard is to make the first piece and measure it before the rest of the batch is released — catching a deviation at this stage costs a fraction of scrapping the whole batch.

Quality control accompanies production to the end: critical dimensions are measured during the batch, and on acceptance the part comes with the agreed documents — from a simple confirmation of conformity to a measurement report of the dimensions marked on the drawing. It is worth agreeing on the scope of inspection at the offer stage, because it affects price and time.

What about changes during production? It happens that the designer corrects a dimension after the order has been placed. The rule is simple: a change always comes as a new drawing revision, sent through an official channel and confirmed by the supplier together with its impact on price and date. Corrections passed on by phone "in passing" are the shortest route to parts made to two different versions of the documentation.

Delivery and invoicing

Finished parts are protected against corrosion and transport damage, then shipped to the customer or held for collection. For larger orders it is worth agreeing on batch labelling — a label with the drawing number, revision and production date costs little, and months later it lets you determine unambiguously which delivery a given piece came from. It is also good practice to check the parts within a few days of delivery — a complaint raised immediately, with a specific dimension and measurement, is resolved quickly and without argument.

Invoicing closes the cycle: an invoice with the agreed payment term, and in ongoing cooperation often consolidated invoices for a period instead of individual documents. It is also the moment for brief feedback — fits, assembly, remarks on the finish. The supplier applies the corrections to the program and documentation, so every subsequent batch is better than the previous one.

What speeds up a job and what delays it

From the supplier's perspective, the difference between a "smooth" and a "difficult" order almost never lies in the machining itself. It lies in communication and the completeness of data:

Most delays therefore arise before the first chip flies. A complete inquiry and prompt decisions can shorten the whole path by several days — at no cost to the customer.

From the first order to an ongoing partnership

The first order is always the most time-expensive: the parties get to know each other, documentation travels back and forth, the program is written from scratch. On subsequent orders of the same part, the supplier uses the existing program and proven process, so execution is faster and more stable in price.

However well the cooperation goes, keep the current documentation — drawings, models, revision log — on your side as well. It is your safeguard: it lets you ask a second supplier for an offer at any moment, compare prices and avoid making production continuity dependent on a single shop.

If the orders keep coming, the natural step is formalising the rules — rates, priority in the queue, material at hand and documentation stored with the supplier. We describe this model in detail in the post on the framework agreement with a CNC subcontractor, and the cooperation terms with Nomatec — a brand of Adreams, based in Zbąszyń, Poland, operating since 2015 — can be found on the B2B cooperation page. Before you send your first inquiry, it is also worth checking whether the supplier suits your parts at all — the post how to choose a CNC machining company will help.

Summary

Working with a CNC subcontractor consists of seven predictable stages: inquiry, NDA, quotation, order, production with inspection, delivery and invoicing. The biggest influence on lead time is not the supplier's machine park but the completeness of the documentation and the pace of decisions on both sides. Those who understand this get their parts faster — at the same price.

Have a part to order? Send the drawing and model via the contact form — you will receive a quote within 48 hours, together with process remarks if anything in the documentation needs clarifying.