SHANGERS / BUYER GUIDE
Colour is not a contact specification.
Two contacts can look similar while having different base materials, surface systems and intended interfaces. A photograph is useful for discussing shape. It is not enough to approve the alloy, plating or electrical performance. For a custom stamped contact, organize the enquiry around what each region of the part has to do.
Separate the base alloy from the surface system
Treat the substrate and finish as separate items in the specification. State the alloy and condition when they are already defined. If they are open for review, provide the application and mechanical requirements rather than selecting a grade by colour. Do not describe a sample simply as 'silver metal' and expect that phrase to control repeat production.
Mark the functional zones
A terminal may have a mating area, a termination area and a section retained in a housing. Show those regions on a drawing. As an example of specification practice, TE Connectivity lists contact base material, mating-area plating and termination-area plating as separate fields for its Dynamic 3000 contacts. That distinction is useful; its particular ratings and dimensions must not be transferred to an unrelated custom component.
Define the finish beyond its name
If plating is required, identify the covered area, the governing specification and the acceptance requirements. Include any thickness or underlayer requirements already established by the design authority. Ask the manufacturer to flag missing information rather than assume that every mention of tin, nickel or gold represents one universal process. State whether selective coverage is necessary and have its availability confirmed for the project.
Describe how the contact is assembled
Provide the mating surface and termination method, plus any housing features that locate the part. The conditions at a soldered region need not be the same as those at a separable contact interface. If a formed offset controls contact location, identify the dimensional reference and allowed variation. Keep mechanical fit questions visible alongside the surface requirements.
Specify verification in the actual context
Do not obtain a current rating from the size or colour of a sample. Tell the supplier which electrical, thermal or mechanical checks your assembly requires and who is responsible for them. Test arrangements and acceptance criteria must be agreed. A drawing review, a material document and a functional test answer different questions; one should not silently stand in for the others.
Keep the sample approval traceable
Record the drawing revision, material specification, finish specification and sample identification together. Where a mating assembly is used for approval, record that configuration as well. If the material or finish changes after sampling, review whether the earlier approval still covers the order. Avoid using an old sample as the only reference when its own specifications are unknown.
Include handling and packaging
Ask how the parts will be separated and protected, especially where tails can bend or critical surfaces can rub together. Specify any cleanliness or orientation requirement rather than assuming it from the product name. Packaging should support the agreed inspection and assembly process, not merely keep the pieces inside a box.
Write the request as a set of decisions
A clear enquiry identifies what is fixed, what is proposed and what still needs review. For example: the housing interface is fixed; the alloy is proposed; plating coverage awaits confirmation. This is more useful than asking for the 'best coating' without an application. It also makes it easier to compare quotations on the same technical scope.
Technical reference: TE Connectivity: Dynamic 3000 contact specification fields. Referenced product specifications are examples, not SHANGERS product ratings.
