Hardware

Custom Magnetic Backings for Pins and Badges: Spec Sheet

Why magnetic backings fail in real use

A magnetic backing looks simple until it fails on a real garment. The badge spins on a blazer, slips on a knit polo, or drags the front piece into a tilt because the magnet is strong enough in hand but weak in the actual wear condition. Buyers often ask for a “strong magnet,” but that is too vague to control production. In practice, performance is set by pull force, magnet footprint, front weight, fabric thickness, and the distance between the magnet and the load center.

Magnetic backs are best for lightweight pins, name badges, and promotional pieces where the user wants fast on-off wear and no needle holes. They are a poor fit for heavy cast ornaments, thick outerwear, or designs that must remain perfectly aligned while walking. If you are sourcing from a factory, write the spec as a measurable assembly requirement: dimensions, tolerances, pull targets, test fabric, and acceptable rotation.

The most common failures are predictable: a magnet that is too small for the front weight, a round backing used on a tall rectangular badge, a backing shell with exposed edges, or a good-looking sample that cannot hold through the intended fabric stack. Fixing those issues starts with a tighter RFQ and a defined wear test.

Core dimensions to lock on the RFQ

Treat the front piece and the magnetic backing as one assembly, not two separate parts. At minimum, state the finished width and height, total thickness, front weight, magnet footprint, garment thickness, and whether the badge must stay level or simply remain attached. If the factory does not know the fabric stack, it will usually overbuild the magnet and create unnecessary bulk and cost.

For small lapel-style products, a common finished stack is 4.0 to 7.5 mm total thickness. The decorative front often contributes 2.5 to 4.5 mm, while the magnetic unit is usually 1.5 to 3.0 mm depending on construction. For better control, specify thickness at the center point and define the tolerance separately for the front and the backing. A practical tolerance is ±0.3 mm for simple two-part assemblies and ±0.5 mm for cast fronts, domed resin, or layered constructions. If the profile is curved, say whether the thickness is measured at the crown or the edge.

For diameter, width, and length, use the real working envelope rather than the artwork size alone. A 25 mm round badge with a zinc-alloy front can need a much larger magnet footprint than a 25 mm stamped steel piece. If the piece is long or rectangular, define the center of gravity and ask the factory to place the magnet under the load center, not just at the geometric center.

Spec line	Buyer should state	Typical factory range
Front size	Diameter or W x H in mm	15–40 mm for badges; 20–35 mm for pins
Finished thickness	Assembled thickness in mm	4.0–7.5 mm
Magnet footprint	Disc diameter or bar length x width	8–18 mm
Thickness tolerance	Allowed deviation	±0.3 to ±0.5 mm
Front weight	Grams per piece	4–18 g for most promo items

Magnet type and pull force

For this category, the practical material choices are ferrite and neodymium. Ferrite is lower cost, less brittle, and acceptable for light promotional badges, but it needs more footprint to achieve useful holding power. Neodymium gives stronger pull in a smaller size, which helps when the front part is heavier or when the badge must stay stable on thicker fabric. The trade-off is cost, sharper snap force, and a higher risk of chipping if parts are handled roughly during assembly or packing.

Do not ask only for “strong enough.” Ask for pull force per set, the fabric thickness used in the test, and the direction of the load. For office shirts and light blouses, many buyers target a lower pull range; for wool uniforms and heavier knitwear, the magnet or bar needs to be noticeably stronger. In RFQs, include the garment type, target wear duration, and whether the item must survive walking, bending, and repeated reaching.

A practical starting point is 0.8 to 1.5 kgf tested through 0.5 to 1.0 mm fabric for lightweight badges, and 1.5 to 3.0 kgf for heavier fronts or thicker garments. These are not universal standards, but they are actionable purchase targets. For coats or layered uniforms, a bar-style pair or wider contact plate is often more reliable than a small round disc.

Magnet option	Best use	Typical pull target	Trade-off
Ferrite disc	Low-cost badges, short events	0.8–1.2 kgf	Lower cost, larger size, weaker hold
Neodymium disc	Premium badges, moderate-weight fronts	1.2–2.5 kgf	Higher cost, stronger snap, more brittle
Magnet bar pair	Rectangular or heavier designs	1.8–3.0 kgf	More parts and tighter assembly control

Attachment geometry and anti-rotation

A badge that turns sideways is usually a geometry problem, not just a magnet problem. The contact area between the garment-facing magnet and the front shell controls whether the piece sits flat or pivots under movement. Narrow, tall shapes are hardest to stabilize because the center of gravity sits above the contact point.

For rectangular or long designs, ask for a matching magnet bar instead of a round disc whenever possible. For circular pieces, a centered disc works well only if the front is light and symmetrical. When the design has a dangling charm, raised enamel, or layered relief, specify either a wider back plate or a second contact point so the front does not tilt. If the item will be worn in public events, add an anti-rotation requirement on the target garment type, not just on a lab fixture.

A useful way to brief the factory is to define the expected behavior: stay level while walking, remain centered while seated, and resist visible twist after repeated arm movement. If the badge must align with a uniform pocket or logo line, the magnet layout should be designed around that visual reference point rather than the center of the artwork.

• Use a wider magnet footprint for tall or narrow badges.
• Match rectangular fronts with bar-style magnets where possible.
• State the garment type used for the wear test.
• Reject designs that rock because the magnet sits too shallow.
• Specify whether the piece must stay level during movement or only during static wear.

Material stack-up and surface protection

The front shell is usually zinc alloy, iron, brass, or stainless steel. Zinc alloy supports deeper relief and cast detail, iron is economical for stamped shapes, brass gives a more premium appearance, and stainless helps with corrosion resistance. The right choice depends on finish, weight, and target FOB price, not just appearance.

The back side needs equal attention. Exposed metal edges can mark fabric, so ask for a recessed magnet pocket or a capped backing where the design allows it. If the backing uses a steel washer or plate, define the plating as well as the substrate. For common commercial work, nickel or black nickel plating is often specified around 0.08 to 0.12 microns on decorative outer layers; more durable retail builds may call for a thicker protective stack or a clear coat over the finish. The critical point is consistency across the lot, not just a good-looking sample.

If the badge will be packed individually, also define whether the magnetic back is separated from the front during packing or pre-assembled. Pre-assembly saves time for the buyer, but it raises the risk of scuffing, magnet snap damage, and finish transfer if the product is not protected properly with tissue, film, or a tray cavity.

Layer	Recommended spec	Why it matters
Front metal	Zinc alloy, iron, brass, or stainless	Controls detail, cost, and weight
Backing shell	Recessed pocket or capped back	Prevents snagging and fabric damage
Plating	Match front finish and define thickness	Reduces wear and color mismatch
Edge finish	Deburred, smooth, no sharp burrs	Lowers return risk and garment snagging

Test methods buyers should request

A sample that feels strong in hand can still fail in wear. Build the test plan into the RFQ or PO so the factory knows what pass means. At minimum, request pull-force testing, rotation or tilt testing, fabric slip testing, and surface inspection after repeated attachment cycles. If the buyer cannot measure it, the supplier will usually interpret it loosely.

For incoming or pre-shipment QC, use AQL 2.5 for general appearance and AQL 4.0 for minor functional items on promotional orders. For premium retail items, tighten the appearance standard and require a wear test on the real target fabric. For most orders, ask for at least 10 attach-detach cycles on each sampled unit and confirm that the front and backing do not loosen, chip, or separate.

A practical test set is simple: hold through fabric for 10 seconds, walk and twist the garment, inspect for edge contact, then repeat the attach-detach cycle. The factory should document the fabric type, pull method, sample count, and any measured slip so the result can be repeated on the next order. If you need a more exact standard, specify the allowable slip distance in millimeters or the maximum degree of rotation after movement.

Test	What to check	Suggested acceptance
Pull test	Magnet holds through target fabric	No detachment under normal wear
Rotation test	Badge stays level	No visible twist after movement
Surface test	No scratches or burrs	No damage to fabric or finish
Cycle test	Repeated attach/detach	No loosening, cracking, or separation

MOQ, lead time, and FOB price bands

The economics depend on whether the factory is using stock magnet sizes or building a custom assembly. If the job uses standard discs, standard stampings, and simple plating, the MOQ can stay relatively low. Once the design needs custom die-cut parts, special bar magnets, or mixed finishes, the MOQ rises quickly because setup, assembly, and QC become more complex.

For planning, a practical MOQ is 300 to 500 pieces for standard magnetic badge builds, 1,000 pieces for custom-shaped fronts or plated assemblies, and 3,000 pieces if you need special packaging, paired components, or mixed-color sets. Typical lead time is 12 to 18 days after sample approval for standard builds, and 18 to 25 days for custom magnet geometry, multiple plating finishes, or special retail packing. Rush orders may be possible, but they usually compress QC and increase scrap risk.

FOB pricing commonly falls around USD 0.75 to 1.60 per piece for simple badge-style magnetic backs, USD 1.60 to 3.20 for heavier or more decorative builds, and USD 3.20 to 5.50 for cast fronts with premium plating or individual retail packaging. Prices vary with metal type, magnet grade, plating complexity, and whether assembly is fully manual or semi-automated. If you need a precise quote, send the front drawing, garment type, target pull force, and packing method in one package.

Keeping front metal, plating, and assembly under one process chain usually lowers handoff risk and shortens sampling time. That matters more than the lowest quoted unit price if you are trying to avoid rework on a repeat order.

What to do next

Write the RFQ as an assembly spec: front size, front weight, total thickness, magnet type, pull target, garment thickness, finish, edge safety, test method, MOQ, and packing format. Ask for one pre-production sample made against the exact fabric type the end user will wear, because a magnet that works on a thin cotton shirt may fail on a wool blazer or knit polo.

If you already have artwork, lock the front dimensions and weight before choosing the magnet size. If you do not, start with the wearer, garment type, and performance requirement: stay flat, stay level, or simply avoid needle holes. Those three decisions usually determine the right magnetic build faster than style discussions do.

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