Quality Control

Custom Enamel Pin Spec Sheet: Field-by-Field Buyer's Guide

Start with a buildable brief, not a mood board

Most pin orders go wrong before tooling starts because the buyer describes the concept but leaves the factory to infer the build. A usable spec sheet starts with measurable fields: overall size, thickness, base metal, plating, enamel type, backing, packing, and approval standard. If you want quotes you can compare, each field needs a number, a finish name, or a closed option list.

For standard custom enamel pins, event giveaways usually land at 20 to 35 mm, while retail-style artwork is more commonly 30 to 45 mm. Soft enamel lapel pins are usually 1.2 to 1.6 mm thick; hard enamel is commonly 1.5 to 2.0 mm because polishing needs more material above the recessed fill. Typical sample lead time is 7 to 10 days, and mass production is 12 to 18 days after sample approval. FOB pricing for a 25 to 30 mm single-color soft enamel pin often lands around USD 0.40 to 0.95 at 100 pcs, USD 0.22 to 0.55 at 500 pcs, USD 0.18 to 0.42 at 1,000 pcs, and USD 0.12 to 0.30 at 3,000 pcs, depending on metal, plating, and backing hardware.

• State maximum overall dimensions in millimeters, not just the logo size.
• Specify whether the outline is full-cut, cut-out, or a simple closed shape.
• Fix thickness before artwork approval because it changes the side profile and weight.
• Choose soft enamel or hard enamel based on texture, cost, and fill tolerance.
• Call out whether the finish should be glossy, matte, antique, sandblasted, or black nickel.

Lock size, thickness, and tolerance

Size drives cost, durability, and how much detail the tool can hold. A 25 mm pin with simple outlines may look fine in a proof, but the same art at 18 mm can force line consolidation, smaller text, or color deletion. Thin pins look light and clean, but they bend more easily and make back hardware feel oversized; thicker pins feel premium but raise metal weight and plating cost.

For most custom enamel pins, perimeter tolerance should be held around ±0.3 mm, with ±0.2 mm on critical internal cutouts where tooling permits. Readable microtext should be at least 1.2 mm high for bold sans-serif and closer to 1.5 mm if the art uses thin strokes or reversed type. Buyers should also define whether dimensions are measured across the enamel border or the outer metal edge, because factories do not always quote the same way.

A practical buying rule is to keep the thinnest visible metal line at 0.3 mm minimum for soft enamel and 0.4 mm minimum for hard enamel if the design includes small type or multiple color breaks. If the art has an asymmetrical silhouette, ask the factory to confirm the center of gravity so the final pin does not hang crooked on garment fabric.

Spec field	Recommended buyer entry
Overall size	28 mm wide x 32 mm high
Thickness	1.5 mm zinc alloy
Tolerance	±0.3 mm perimeter, ±0.2 mm critical cutouts
Text height	1.2 mm minimum, 1.5 mm preferred for fine detail
Measurement basis	Outer metal edge or enamel edge, stated explicitly

Choose the right metal and plating

Base metal and plating are not cosmetic footnotes; they determine hardness, edge sharpness, and how the pin ages in distribution. Zinc alloy is the common choice for complex shapes and lower tooling risk, while iron is often used for flatter designs where cost matters more than sculpted depth. Brass holds fine detail well and can feel more premium, but it usually carries a higher FOB and is best used when the order justifies the extra metal cost.

Plating should be written as a specific finish, not just “gold” or “silver.” Typical decorative plating thickness in factory quote structures is often about 0.03 to 0.05 microns for bright decorative finishes, though actual build varies by process and bath control. Antique finishes are useful when you want contrast in recessed areas, but they also expose tooling marks more clearly if the die lines are rough or the polish stage is skipped.

For pricing, a simple 25 mm soft enamel pin in zinc alloy with butterfly clutch often quotes around USD 0.40 to 0.75 at 100 pcs, USD 0.24 to 0.48 at 500 pcs, USD 0.18 to 0.36 at 1,000 pcs, and lower at 3,000 pcs or above. Add black nickel, brass, hard enamel, epoxy dome, or custom backing and the unit price usually rises. Buyers should ask for the quote to separate metal cost, plating cost, backing cost, and packaging cost so substitutions are visible.

• Name the base metal: zinc alloy, iron, brass, or copper.
• Name the finish: shiny gold, shiny nickel, black nickel, antique brass, antique silver, or matte black.
• Ask whether plating covers all exposed edges, including back and side walls.
• State whether the finish can have intentional dark recesses or must be fully bright.
• Request a sample photo under neutral light before approving the finish standard.

Specify enamel type and color control

Soft enamel and hard enamel behave differently, so the specification needs to say which visual outcome matters more: texture or flatness. Soft enamel leaves recessed color areas below the metal border, which adds tactile separation and usually lowers cost. Hard enamel is polished flat after filling, so it feels smoother and looks more jewelry-like, but it is less forgiving if the art has too many narrow islands or stacked color boundaries.

For color control, define the exact number of colors, the Pantone references, and whether black or white outlines are part of the approved design. If the artwork uses gradients, gradients should be disallowed unless the factory confirms a printed-inlay or UV-print process, because standard enamel filling cannot hold smooth blends. Glitter, translucent enamel, glow-in-the-dark pigment, and pearl powder should each be treated as separate options and priced separately.

As a production rule, soft enamel recess depth is commonly about 0.3 to 0.5 mm below the raised metal line. Hard enamel is typically polished flush to within about 0.1 mm of the metal surface after multiple fill and bake cycles. If a buyer wants a specific color match, the RFQ should say whether Pantone match tolerance is acceptable within a visual delta of roughly one shade step or whether a physical lab-dipped chip is required.

Color spec	What to write	Risk if omitted
Pantone	Pantone 186 C for red	Shade drift between samples
Outline	Black metal line, no printed outline	Unclear separation between colors
Effect	No glitter, no transparency	Supplier substitutes easier effect
Finish level	Soft enamel recessed 0.3 to 0.5 mm	Incorrect visual depth

Set attachment, back hardware, and safety rules

A pin can pass artwork approval and still fail in the field if the attachment is wrong for the garment or event type. Butterfly clutches work for light to medium pins, but heavier pins or badges worn on jackets may need rubber clutches, deluxe clutches, or magnetic backing depending on fabric damage risk. If the buyer does not specify the back, factories often default to the cheapest hardware that technically fits, which is not always the right choice for retention or user comfort.

For most lapel pins under 30 mm and under about 8 g, one post is often enough if the shape is balanced; above that, two posts reduce rotation and sagging. Post diameter is commonly 1.0 mm for standard pins and 1.2 mm for stronger retention, with post length usually around 6 to 8 mm depending on plating build and clutch style. If the design will go on delicate fabric, add a note that no sharp rear edges, exposed solder points, or loose hardware are acceptable.

If the product will be worn at conferences, concerts, or by retail staff, ask for a simple pull-test standard on the pre-production sample. A practical acceptance target is no post failure under a 2 to 3 kgf light pull on the sample and no visible wobble after clutch engagement. For security-sensitive wear, magnetic backs reduce fabric damage but lower retention, so they should be specified only when that tradeoff is acceptable.

• Specify one post or two posts based on size and center of gravity.
• Name the clutch type: butterfly, rubber, deluxe, or magnetic.
• State any fabric sensitivity requirement.
• Ask for anti-rotation placement if the shape is asymmetrical.
• Request pull-test confirmation on the production sample if the pin is heavy.

Control line art, cutouts, and edge finish

The most common rework trigger is not color; it is geometry. Narrow bridges, sharp internal corners, and tiny openwork features can break in polishing, plating, or packing, especially on zinc alloy pieces with thin cross-sections. If the design has cutouts, the spec should say whether the opening is functional, decorative, or both, because that changes how aggressively the factory can simplify the shape.

As a practical buying rule, keep minimum metal bridge width above 0.3 mm for simple shapes and above 0.4 to 0.5 mm when the design includes cutouts, moving elements, or heavy plating contrast. Internal corners should be relaxed where possible because sharp inside radii increase tool wear and can leave uneven enamel edges. A polished edge should be defined as burr-free and finger-safe, not merely shiny.

If the artwork includes very small negative space, ask the supplier to flag any area below the factory’s normal tool limit before sampling. That usually catches the thin bridge that would snap during polishing or the tiny island that would fill poorly and create a trapped void. For mixed-detail designs, the best RFQ language is not “keep all details,” but “retain all legible details above the agreed minimum line width.”

Geometry item	Buyer spec	Typical factory issue
Minimum bridge	0.4 mm minimum	Breakage during polishing
Internal corner	Rounded where possible	Tool wear and uneven fill
Cutout wall	No burrs, no flash	Sharp edges in final pack
Edge finish	Finger-safe, smooth	Returned as rough or sharp

Define packaging and carton requirements

Packing is part of the spec sheet because it affects scratch rate, presentation, and unit cost. A pin packed loose in a polybag ships cheaper, but plated surfaces can rub against each other in transit, especially on antique or mirror finishes. Backing cards, OPP bags, and individual pouches should be treated as separate line items so the quote reflects the real presentation standard.

For distributor programs, backing cards are often the simplest upgrade because they protect the pin and give you a branding surface without changing the metal build. If the order is retail-facing, ask the factory to state carton quantity, inner box size, and master carton limits so you can avoid damage from overpacked cartons. A common packing ladder is loose bulk packing for lowest cost, single OPP bag for basic protection, card and bag for retail presentation, and gift box for premium sets.

Packaging also affects lead time. Loose packed orders may stay within the standard 12 to 18 day production window, while printed backing cards or custom gift boxes often add 3 to 7 days. For FOB comparison, buyers should ask for a separate price on each packing option so the quote does not hide the cost of presentation behind a low unit number.

If you need sharper logistics control, specify carton targets such as 500 to 1,000 pcs per master carton, no more than 15 to 18 kg gross weight, and individual bagging for all plated surfaces. That keeps freight handling predictable and reduces the chance of carton crush or surface rub marks.

• Write packing as a mandatory field, not an afterthought.
• State whether each pin is loose, bagged, carded, or boxed.
• Define carton quantity and maximum carton weight.
• Ask for scratch protection between plated pieces.
• Confirm whether spare clutches are included or packed separately.

Build an RFQ factories can answer cleanly

Turn your next RFQ into a line-by-line spec sheet before you ask for price. Start with size, thickness, base metal, plating, enamel type, attachment, and packing, then lock the tolerances and approval rules so the supplier is quoting the same product you are buying. That single step usually removes most quote noise and makes sample approval faster.

If you are comparing factories, send the same spec sheet to each one and prohibit substitutions unless they are marked clearly in writing. For mixed programs, keep one master format across pins, coins, badges, and keychains so future reorders do not drift on thickness, color, or backing hardware. A good buyer sheet should also include target quantity tiers, requested FOB Incoterm, sample charge, sample lead time, production lead time in days, and any packaging surcharge so every factory answers the same commercial question.

A simple checklist before release is enough to catch most errors before tooling starts:

• Confirm exact size in millimeters and measurement basis.
• Lock base metal, plating, enamel type, and backing.
• Set tolerance, readable text minimums, and cutout limits.
• State packaging, carton rules, and whether a card is required.
• Request sample photo approval and a golden sample for mass production.
• Ask for price breaks at 100, 300, 500, 1,000, and 3,000 pcs.
• Require all substitutions to be called out before PO acceptance.

A clean spec sheet usually produces cleaner quotes. It also makes it easier to compare a USD 0.32 pin against a USD 0.46 pin because you can see whether the difference comes from brass instead of zinc, hard enamel instead of soft, or better packaging instead of hidden compromises.

Have a project? Send your artwork and target quantity and we’ll reply with a detailed quotation within 12 working hours.