Metal Stamping Burr Direction: How to Specify Edge Quality in an RFQ
Burr direction can affect handling, fit, coating, sealing, and electrical contact. This RFQ guide helps buyers define the edge condition instead of relying on a vague deburring note.
Die design decisions influence the cut edge; review how progressive die clearance affects burrs and tool wear.
How stamping creates a burr
Shearing separates sheet or strip material through punch and die clearance. The cut edge may include rollover, a burnished zone, fracture, and a burr. Burr height and shape are influenced by material, thickness, tooling condition, clearance, and process setup.
A burr is not automatically a defect in every application. Its significance depends on where it faces, whether it interferes with assembly, and whether the edge is accessible to operators or adjacent components.
Why burr direction matters
A burr directed toward a mating surface may prevent seating, scratch a coating, or create a local gap. In electrical assemblies, the edge may affect contact or insulation clearance. On handled parts, an exposed sharp edge can create a safety concern.
Design and process review
Confirm the functional interface, critical features, production quantity, and inspection method before tooling or machining approval.
Purchasing and quality alignment
Document material, revision, acceptance requirements, sample approval, packaging, and delivery expectations in the RFQ.
Show the preferred burr direction on the drawing or identify the side that must remain free of burrs. For parts with multiple formed features, clarify direction relative to the final formed geometry, not only the flat blank.
Define a measurable edge requirement
If edge quality is critical, specify a maximum burr height or another measurable acceptance criterion tied to function. Identify critical edges and distinguish them from edges with no special requirement.
A blanket “deburr all edges” can add cost and may alter small features. Call out only the edges that affect safety, fit, sealing, electrical contact, or coating performance, and agree how they will be inspected.
Coordinate burr direction with part design and tooling
Review blank orientation, forming sequence, die access, part nesting, and the direction of mating components. The best orientation may depend on whether the feature is punched before or after forming and whether a secondary operation is required.
A DFM review can identify where burr control conflicts with tool access or material flow. For a new program, include assembly context and indicate which faces are cosmetic or functional.
Tie inspection to the application
Visual checks can identify obvious sharp edges, but dimensional burr limits may require a defined gauge or measurement method. Agree sampling frequency, report format, and treatment of edges that are difficult to access.
For coated parts, clarify whether burr height is checked before or after finishing and how coating coverage at cut edges is evaluated. This avoids disagreement between the stamped component and final assembly requirements.
RFQ checklist
Attach the 2D drawing, 3D model or flat pattern, material and thickness, quantity, critical edge map, preferred burr direction, finish, inspection requirements, and destination. Include sample or assembly context when edge orientation is not obvious.
Review custom metal stamping capability and share your requirements through request a manufacturing quote.
Discuss Your Manufacturing RFQ
Share your current CAD, drawing revision, material, target quantity, critical-to-function requirements, inspection expectations, and delivery destination. The engineering team can review manufacturability before quotation.