From Drawing to Sample: What to Expect When Prototyping a Custom Spring

You've got a drawing, or maybe just a sample of the spring you need replaced, and you're not sure what happens between sending that to a manufacturer and having a working prototype in hand. Here's what the process actually looks like.

Step 1: Share what you have

We accept drawings in any format — PDF, DXF, STEP or a hand sketch — as well as a physical sample. If you're starting from a sample rather than a drawing, we measure it directly: wire diameter, outer diameter, free length, active coils, end configuration. If you're starting from a drawing, we check it against the parameters that actually determine performance, the same ones covered in how to specify a custom spring.

Step 2: We flag anything that won't manufacture cleanly

This is the step people don't expect. A design that works on paper doesn't always translate directly into a manufacturable part — a hook radius too tight for the wire diameter, a pitch inconsistent with the required solid height, tolerances tighter than the application actually needs. We'd rather raise this before cutting wire than after.

Step 3: Material and finish confirmation

Based on your load, environment and cycle life requirements, we confirm the material grade and surface finish. If you're unsure which grade fits your application, this is the point where we ask about your operating environment rather than guessing.

Step 4: Prototype run

We manufacture a low-MOQ prototype batch — not the same tooling commitment as a full production order, and the right stage to catch any issue before you commit to volume. Typical prototype turnaround runs a few weeks depending on material availability and complexity.

Step 5: Testing and sign-off

We check free length, load at your specified deflection, and dimensional conformance before the prototype ships. You test it in your actual assembly — this is the step no lab measurement fully replaces.

Step 6: Move to production, or iterate

If the prototype performs, we move to bulk production against the confirmed spec. If it doesn't quite match, we adjust and run again — better to iterate at prototype scale than discover a problem in a container of finished parts.

If you already know your spring's parameters, our guide on specifying a custom spring is the right starting point before you send us a drawing.