Focus processes: fine blanking and thinning deep drawing
What defects occur in thinning deep drawing?
Answer
Where deep drawing defects occur on the part A drawn cup with five fault zones marked: earing on the top edge, wrinkling in the flange and wall, tearing at the bottom radius, thinning in the wall, and draw marks on the wall from tooling wear. 1 2 3 4 5 1 Earing — scalloped top edge from planar anisotropy in the sheet 2 Wrinkling — blank holder force too low, flange unsupported 3 Tearing — draw ratio too high, die radius too tight, friction too high 4 Thinning — wall stretched as it passes the die radius 5 Draw marks — tool wear or lubrication breakdown at the die radius Defect map. Almost every remedy for these is a tooling change rather than a material change — which is why deep drawing tooling is a design problem first and a production problem second. Defect Appearance Usual cause Usual remedy
Sources
- Drawn Sheet Metal & Deep Drawing: Complete Guide | BalfordWhere deep drawing defects occur on the part A drawn cup with five fault zones marked: earing on the top edge, wrinkling in the flange and wall, tearing at the bottom radius, thinning in the wall, and draw marks on the wall from tooling wear. 1 2 3 4 5 1 Earing — scalloped top edge from planar aniso...
- Resources — Case Studies, Stock Parts & Cost CalculatorWhat a complete RFQ contains: drawing and 3D model at the same revision, material grade and temper, volume, finish, critical tolerances and required documentation. Also the five questions to ask about every quotation, the wall thickness measurement position, and the four IMDS high-risk points on sta...
- Resources — Case Studies, Stock Parts & Cost CalculatorWhich process the geometry actually needs, and how much secondary machining drawing can remove. Deep drawing materials Steel, stainless, aluminium, brass and copper — and the formability each one actually offers. Ironing and wall thinning How a thinned wall holds the inside and outside diamete...
- Deep Drawing Defects and Remedies | BalfordDefect Appearance Usual cause Usual remedy Draw marks / scoring Longitudinal scratches on the wall Tooling wear, galling, inadequate lubricant Polish the die radius; re-coat or re-polish tooling; review lubricant Bottom fracture Split across the base Punch radius too small; too little material avail...
- Deep Drawing Defects and Remedies | BalfordHome › Resources › Defects and Remedies Engineering reference Deep Drawing Defects and Remedies Updated September 26, 2026 · Balford Technical Team Direct answer: The eight failures that come up in every deep drawing job, with the cause and the tooling-side remedy. Where it goes wro...
- Deep Drawing Calculation: A Worked Example | BalfordDeep drawing: process, materials and defects Precision deep drawn components Deep draw force calculator Ironing and wall thinning Deep drawing materials guide...
What an engineer still needs from you
- material and material condition (grade, temper)
- material thickness, plus the key diameter, height and wall thickness
- tolerances, burr direction and the visual acceptance standard
- annual volume - it decides whether tooling is single-hit, progressive or transfer
- surface finish, and any secondary machining, annealing or plating
Need a DFM feasibility assessment for your project?
Send the engineering drawing (STEP or PDF) with the material grade, thickness and annual volume. Balford engineers then check it against the process window - draw ratio, wall thickness, tolerances, blank and tooling route - and come back with what is feasible and what is not. An answer on this page cannot replace that review.
Upload a drawing for DFM reviewHow the DFM review worksRelated questions
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This page is an engineering answer, not a quotation and not a dimensional acceptance. It is generated from Balford's published material and held to the verified company fact sheet.