Most spring manufacturers are built around volume. When a buyer needs 50 pieces for a test rig or 500 pieces to cover a pilot build, the order lands in an awkward gap: too small for the volume houses, too specific for a stockist.
This is the model we work in, so here is what the process looks like from the buyer's side.
Quantity
Prototype runs are a normal order, not a favour. What matters to us is not the first order quantity but whether the part is something we can make repeatedly — the first sample is quoted on the assumption that production may follow, and it is priced accordingly.
Tooling
Springs are formed rather than moulded, so most parts need no dedicated tooling. Where a part needs a fixture, a special end form or a custom mandrel, that cost is identified on the quotation rather than discovered later.
Lead time
Two clocks run at once: the time to make the part, and the time to obtain the wire. For common grades the wire is usually in stock and the part sets the schedule. For uncommon alloys — precipitation hardening and nickel grades in particular — the wire mill sets the lead time, and it can be several weeks regardless of how simple the spring is. Ask about material availability early.
Approvals
The sequence that works: drawing, quotation, sample, dimensional report, approval, production. Skipping the dimensional report step is the most common cause of a dispute later, especially for parts assembled by a third party.
What to send
A drawing, or a sample, or a clear description of the application plus the dimensions you care about. If you have a specification from a previous supplier, send that too — matching an existing part is usually easier than starting from a description.