Focus processes: fine blanking and thinning deep drawing
What is thinning deep drawing (ironing)?
Answer
Ironing in deep drawing: how wall thinning holds both the inside and the outside diameter Ironing - also called wall thinning or wall ironing - is the operation that turns an ordinary deep drawn cup into a precision housing. A drawn cup usually has a wall that thickens toward the rim and a surface that carries the marks of the draw. Ironing pushes that cup through a ring die whose bore is slightly smaller than the cup's outside diameter, so the wall is squeezed thinner between a polished punch on the inside and a polished die on the outside. The consequence is the reason engineers specify it: the die sets the outside diameter, the punch sets the inside diameter, and both surfaces are burnished in the same pass.
Sources
- Ironing in Deep Drawing: Hold Both ID and OD | BalfordIroning in deep drawing: how wall thinning holds both the inside and the outside diameter Ironing - also called wall thinning or wall ironing - is the operation that turns an ordinary deep drawn cup into a precision housing. A drawn cup usually has a wall that thickens toward the rim and a surface t...
- 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...
- Drawn Sheet Metal & Deep Drawing: Complete Guide | BalfordComplex deep drawing and precision stamping Ironing (wall thinning) Ironing in deep drawn stamping Ironing instead of machining Ironing tolerances and surface finish Ironing for solenoid valve housings Ironing vs forging and casting Process comparisons Deep drawing vs press forming Deep drawn vs pro...
- Best Deep Drawn Metal Parts Suppliers in 2026: The Buyer's Shortlist | BalfordPresses up to 1,700 t, draw depths up to 16 in, plus welding and 5-axis laser cutting in the same plant Steel only, and neither diameter nor tooling lead time is published Millions of small parts per year, tolerance-critical Stueken Purpose-built for very high volume precision deep drawing Low-volum...
- 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...
- Drawn Sheet Metal & Deep Drawing: Complete Guide | Balforddesign decision made while the die is still on the drawing board, not after tryout. 5. Ironing: when you want the wall thinner on purpose Ironing is a deliberate thinning operation. The part is pushed through a die whose clearance is less than the wall thickness, so the wall is squeezed thinner as i...
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
- What is fine blanking?
- Fine blanking vs conventional blanking: which should I specify?
- What edge quality does fine blanking achieve?
- Which materials and thicknesses suit fine blanking?
- What tooling does fine blanking need and what drives its cost?
- Fine blanking vs laser cutting vs machining for a flat functional part?
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.