I need to specify metal temper when requesting a precision shim quotation | INNOETCH

Temper should be treated as a required material detail when requesting a precision shim quotation, especially for parts that control preload, alignment, contact force, sealing pressure, wear compensation, or spring return. For simple low-stress spacing shims, a clearly noted soft or annealed condition may be sufficient, but for stainless steel, copper, nickel, aluminum, molybdenum, or alloy shims used in electronics, semiconductor, optical, medical device, and precision mechanical assemblies, leaving temper open can push the supplier into assumptions that do not match the real application.

Why temper changes both manufacturability and shim performance

A precision shim is often treated as a flat thickness-controlled part, but its function is not always limited to spacing. Those behaviors depend on the incoming metal condition, not on the etching process itself. Photochemical etching produces burr-free edges, fine slots, smooth openings, and consistent thin features without hard tooling, but it does not create the base hardness, yield strength, or residual stress state of the material. Those properties are established by the mill and by the rolled condition supplied to the manufacturer.

The same nominal alloy can be available in annealed, quarter-hard, half-hard, hard, full-hard, or spring-like conditions depending on material family and supply form. These conditions differ in bendability, stiffness, edge response, stress relief behavior, and resistance to distortion during cleaning, etching, stripping, inspection, and packing. For thin etched shims with narrow tabs, small holes, teeth, notches, or complex patterns, material stiffness can also affect how easily parts are handled without bending or damage before packaging.

When temper can be simplified and when it must be explicit

Not every shim inquiry requires a highly specific metallurgical temper designation at the first contact, but the level of detail should match the functional risk. The risk rises quickly when the shim performs any mechanical or contact-related function. In those cases, temper should be defined together with material grade, nominal thickness, dimensions, tolerances, and quantity.

• Static spacing shims:temper can often be simplified if the part is not bent, not loaded dynamically, and not required to control force or spring return.
• Adjustment and alignment shims:hardness and stress state matter because flatness during mounting and repeatable fit affect assembly accuracy.
• Sealing or compression shims:material condition affects how the shim responds to clamping pressure and whether it maintains intended contact over time.
• Formed or laminated shims:temper must be reviewed early because bendability, springback, cracking risk, and post-etch handling depend on material condition.

If the exact temper name is not yet known, it is better to describe the operating requirement than to write “standard material.” A hardness range, such as a requested HV band, is often more useful than a vague note because “standard” can vary by supplier, region, and stock availability.

How temper information prevents misleading quotations and avoidable revision loops

When temper is omitted from an RFQ, two suppliers may appear to quote the same shim while actually pricing different material conditions. One may assume a lower-cost soft temper suitable for simple spacing, while another selects a harder or more controlled condition to support flatness, spring function, or cleaner handling. The resulting prices are not directly comparable, and the lower quotation may not represent a usable part for the intended assembly.

Early temper disclosure also reduces engineering rework after quotation. If a harder or stress-relieved condition is identified later as necessary, material availability, process controls, inspection focus, handling methods, and feasibility review may all need to be updated. For custom etched metal components, INNOETCH supports engineering review from prototype development through production, and that review becomes more accurate when material, thickness, geometry, function, and material condition are aligned from the start. This is especially relevant for precision shims and elastic elements, where small differences in hardness or residual stress can affect flatness, assembly repeatability, and long-term dimensional stability.

What to include before requesting samples or formal pricing

A practical shim quotation package should give the supplier enough information to evaluate process fit, material suitability, and inspection requirements without forcing unnecessary assumptions. Before sending drawings or samples, it helps to confirm the items below.

Information item	What to specify	Why it matters
Material grade	Alloy family and grade, such as stainless steel, copper, nickel, aluminum, or molybdenum	Grade alone does not define mechanical behavior, but it sets the available temper options and etching characteristics
Thickness	Nominal thickness and any thickness tolerance requirement	Shim function often depends on thickness control as much as outline geometry
Temper or hardness	Named temper, hardness range, or stated functional requirement	This affects flatness, stiffness, formability, handling, and assembly performance
Part function	Static gap, spring contact, alignment, sealing, electrical contact, heat path, or wear compensation	Functional context helps engineering select a suitable material condition when the exact temper is not yet fixed
Critical features	Slots, holes, tabs, notches, edge contact zones, flatness needs, and surface or cleanliness requirements	Feature geometry and quality expectations influence process controls and inspection planning
Quantity by stage	Prototype, pilot, and production volumes if available	Stage-based quantity supports a realistic review of sample needs and production controls

For project review, drawings, material specifications, dimensions, tolerances, quantity and application requirements can be sent to nico@innoetch.com. If temper is still under selection, describe whether the shim is static or dynamic, whether it will be bent or formed, whether it must resist compression set, whether it needs spring return, whether it requires wear resistance, and whether it must remain flat after etching and packaging. That functional description allows engineering to recommend a workable direction instead of quoting against an unsuitable default.

What to verify before sample approval and production release

For precision shims, the approved sample should reflect the material condition that will be used in production, because a shim made in the wrong temper can pass a quick visual check while failing in assembly. Before approval, confirm that the sample matches the quoted material grade and thickness, review edge quality and feature definition, check flatness in the expected mounting condition, and assess whether the part handles forming, clamping, or spring contact as intended. If hardness or stiffness is critical, include that verification in the sample approval record so production is not released against an ambiguous material description.

Frequently Asked Questions

Can a shim be quoted if I do not know the exact temper name?

Yes, but the quotation will be more reliable if you provide the shim’s function, hardness expectation, assembly loads, forming steps, and whether the part must spring back or remain static. A clear functional requirement is more useful than leaving temper blank.

Is temper less important for very thin shims?

No. Thin shims can be more sensitive to material condition because stiffness, handling distortion, flatness, and response to clamping or flexing are often more noticeable in very thin metals.

Why do two shim quotations differ when both say stainless steel?

The quotes may be based on different tempers, thickness tolerances, inspection levels, or material supply conditions. Temper should be confirmed in writing before comparing prices or approving a supplier.

Should temper be confirmed again before production after prototype approval?

Yes. If the prototype was used to validate function, the approved material grade, thickness, and temper or hardness range should be carried into the production specification to avoid unintended material changes. In actual projects, Innoetch can help review materials, drawings, samples and application conditions for a more suitable manufacturing and application approach. For project-specific review, customers can provide drawings, samples, material specifications, dimensions, tolerances, quantity, application conditions and delivery requirements to Innoetch.