The Buyer's Guide to Purchasing Magnets

Reading the line item

A magnet spec is a short stack of codes, and each one moves price, lead time, or both. Decode before you quote:

Quotes you can actually compare

Magnet quotes diverge because suppliers quietly quote different things. Force a common basis in the RFQ — the RFQ preparation guide has the full checklist; the buyer's short version:

• Same commercial terms: Incoterms, currency, payment terms, and validity period stated — a 30-day-valid FOB China price and a landed U.S. stock price are different products.
• Landed cost, not unit price. Duty (including current Section 301 exposure on Chinese magnets), freight, brokerage, and inventory carrying cost belong in the comparison — the arithmetic is in the landed cost guide.
• Tooling separated from piece price. Amortized tooling hides in unit prices and makes the high-MOQ quote look cheaper than it is. Line-item it.
• The same magnetization state, coating spec, and acceptance criteria. If one quote excludes magnetizing or assumes a thinner plating spec, it isn't lower — it's incomplete.
• Documentation included. CoC with lot traceability and material certs should be in the price; a supplier who charges extra for proof is telling you something.

MOQs, lead times & expedites

The floors are physical, not commercial — press setups, furnace loads, plating batches — so pushing on them works differently than with machined parts. The MOQ & lead-time guide covers the anatomy; the working rules:

• Custom sintered parts run in weeks-to-months, with new tooling adding more up front. The calendar you can compress is mostly freight, which is why the air-vs-ocean call gets made late and expensively.
• Stock sizes ship in days. Before accepting a custom lead time on a routine part, check whether a catalog size covers it — the fastest expedite is not needing one. U.S. stock exists for exactly this.
• Expedite the process honestly: partial shipments from the first plating batch, air freight on a split lot, or paying for a priority furnace slot are real options; “just make it faster” is not.
• Reorder point beats expedite. For repeat parts, set the reorder trigger to consume the real quoted lead time plus policy buffer — then the expedite conversation mostly disappears.

The clean PO

The PO is where quotes become enforceable. Beyond part number, price, and date, the magnet-specific lines that prevent the classic disputes:

Receiving without disputes

• Check the paper before the parts: CoC lot numbers present and matching the cartons, material cert attached for the melt lot. That's a two-minute check that catches the most consequential failures.
• Pull the sample per the plan on the PO — dimensions on the toleranced features, and the magnetic acceptance property if you have the fixture. If you don't have a fixture, that's an engineering conversation (section 07), not a skipped check.
• Handle like the brittle, snapping-together product it is. Receiving damage — chipped edges from parts jumping onto steel tables — gets billed as supplier quality if nobody watches the unboxing. Non-magnetic tools and spacers at the inspection bench.
• Quarantine, don't return, on a suspected failure. Re-measure with a second operator, cross-check against the retained reference samples, then raise it with data. Fixture drift causes a real share of “failures,” and a supplier will engage far faster with numbers than with a rejection slip.

The reorder traps

The first order gets everyone's attention; the trouble arrives on reorder five. The patterns:

• “Same as last time” drift. Reorders placed by email description instead of drawing revision accumulate small divergences — always reference the controlled revision, even for the twentieth reorder.
• Lot spread showing up as a “change.” ±3–5% part-to-part and lot-to-lot magnetic variation is normal and conforming. A line that suddenly can't tolerate it has a design margin problem, not a supplier problem — but it lands on the buyer's desk first.
• The silent resource. Same trader, different factory, no notification — the qualification file no longer describes your part. This is why the site-change clause from the qualification guide belongs on the PO.
• Price creep against a falling index. Rare earth pass-through should move both directions. Track your price against the index trend from the price volatility guide and ask about the gap.
• Tooling ownership fog. If you paid for tooling, the PO should say you own it and that it's released on request — discovered at the worst possible moment otherwise, as the second-sourcing guide details.

When to pull in engineering

Buyers get pressured to make calls that are actually design decisions. Escalate — quickly and without guilt — when:

• A supplier proposes an “equivalent” grade or temperature class. Sometimes it's fine; only the load line and thermal profile say so.
• A quote comes back with tolerance or coating exceptions to the drawing. Cost-saving relaxations are great — when engineering accepts them on the record.
• The acceptance criteria on the drawing aren't measurable as written (“fully magnetized,” “4,500 gauss”). Get them converted to enforceable form before the PO, not during the dispute.
• A repeat part's rejections trace to lot spread rather than nonconformance — the fix is design margin or a sorted-supply agreement, both engineering calls.

Related: RFQ preparation guide · quality documentation guide · MOQs, lead times & tooling