Metal Stamping Processes: Operations, Die Types and When Each Fits
A stamping die cuts, bends, forms or draws sheet metal in a press stroke. This page covers the operations, the die types that combine them and the volume where each one starts to pay off.
Stamping operations
Every stamped part is a sequence of these. A die combines several of them, one per station.
| Operation | What it does | Watch for |
|---|---|---|
| Blanking | Cuts the outside shape of the part from strip or sheet. | The burr sits on the side away from the punch. The edge has a smooth shear band and a rougher fracture band. |
| Piercing | Punches holes and slots inside the part. | Keep hole diameter at or above material thickness. Stainless and hard tempers need more. |
| Notching and trimming | Removes metal from an edge or cuts the part to final outline. | Trim lines set the burr side and the edge that mates with other parts. |
| Lancing | Cuts and lifts metal without removing a slug. Makes tabs, louvers and clips. | Lanced features can distort the web next to them in thin material. |
| Bending | Folds metal along a straight line with a V, U or wipe die. | Springback and grain direction decide the final angle and the minimum radius. |
| Forming and embossing | Raises ribs, dimples and beads that stiffen a flat area or locate a part. | Local thinning shows up at sharp radii and deep embosses. |
| Coining | Squeezes metal under high force to hold a thickness, flatten an edge or sharpen a detail. | Needs far more tonnage than blanking the same outline. |
| Extruding | Pulls a collar from a pierced hole so a screw gets more thread engagement. | Common for tapped holes in thin sheet. The collar height is limited by thickness. |
| Drawing | Pulls flat metal into a cup, box or shell. | Depth per draw is limited, so deep parts need redraws and sometimes an anneal. |
| Fine blanking | Clamps the sheet and shears with tight clearance to give a fully sheared edge. | Tooling costs more. It suits thick parts such as gears, cams and levers. |
Die types
The die type sets the tooling cost, the piece price and how many parts a shop can make per hour.
Single stage die
One operation per press stroke. Parts move between dies by hand or by robot. Low tooling cost, high labor per piece, so it suits short runs and simple parts.
Compound die
Blanks and pierces in one stroke. Parts come out flat and the hole to outline relationship is tight. Limited to flat parts with few features.
Progressive die
A coil strip advances through a row of stations. Each station does one operation and a finished part drops off at the last. The default for high volume parts that stay on a carrier strip.
Transfer die
Parts are cut from the strip early, then fingers move them station to station. It handles larger and deeper parts than a progressive die and allows operations on every face.
Deep draw die
Pulls flat blanks into cups and shells over several draws. Runs as a single die, a progressive set or a transfer line depending on depth and volume.
Fourslide or multislide
Cam driven slides form wire or strip from several directions. It makes springs, clips and complex bends that a press die handles poorly, with low tooling cost.
Which process fits which volume
Typical ranges collected from how shops usually quote. They are not promises. The shop that quotes your part sets the real numbers.
| Process | Typical part | Typical annual volume | Typical tooling | Typical lead time |
|---|---|---|---|---|
| Single stage die | Simple flat parts and short runs | Under 50,000 | $2k to $20k | 4 to 10 weeks for tooling |
| Compound die | Flat parts that need flatness and hole to outline accuracy | 5,000 and up | $5k to $40k | 6 to 12 weeks for tooling |
| Progressive die | Flat and formed parts with many features | 50,000 and up | $10k to $80k | 10 to 20 weeks for tooling |
| Transfer die | Bigger or deeper parts that leave the strip | 20,000 and up | $20k to $150k | 12 to 24 weeks for tooling |
| Deep draw | Cups, shells, cans and closed enclosures | 25,000 and up | $15k to $100k | 12 to 20 weeks for tooling |
| Fourslide or multislide | Clips, springs, terminals and wire forms | 100,000 and up | $3k to $20k | 6 to 12 weeks for tooling |
| Laser blank plus press brake | Prototypes and low volume brackets | Under 10,000 | Little or none | 1 to 4 weeks |
| Fine blanking | Thick flat parts with a fully sheared edge | 50,000 and up | $40k to $200k | 14 to 26 weeks for tooling |
Typical design limits
Starting points for a first print review, not specifications. The shop confirms them against your material and temper.
- Pierced hole diameterAt least 1 times material thickness in mild steel. Use 1.5 to 2 times in stainless and spring tempers.
- Hole to edgeAt least 1.5 to 2 times thickness, or the edge bulges.
- Hole to bend lineAt least 2 times thickness plus the bend radius, or the hole stretches into an oval.
- Inside bend radiusAt least 1 times thickness for ductile steel. Larger for aluminum 6061 and hard tempers.
- Bend reliefA notch at least as wide as the material is thick, so the metal does not tear at the corner.
- Flange lengthAt least 2.5 times thickness plus the bend radius, so the flange stays in the die while it bends.
- First drawA blank to cup diameter ratio of about 1.8 to 2 in mild steel. Anything deeper needs redraws at about 1.2 to 1.4.
Burr height limits and tolerances that cost extra cover the two callouts that move price most.
How a stamped part gets made
From print to shipment. Tooling comes first, so the schedule is set by the die and not by the press.
Review the print
The shop checks material, thickness, tolerances and features, then flags what raises tooling cost. Most price changes come from this step.
Design and build the die
The tool room lays out the strip, designs the stations and builds the die with wire EDM, milling and grinding. Typical tooling time is 6 to 24 weeks.
Tryout and first article
The die runs in the press, samples are measured against the print and the buyer approves them before production starts.
Run from coil
Coil feeds the press at a set stroke rate. Sensors watch for misfeeds and short feeds while the operator checks parts on a schedule.
Secondary operations
Parts that need more than the die can do go on to deburring, tapping, welding, plating or assembly.
Inspect and ship
The shop samples against the control plan, packs against rust and damage and ships against the release schedule.
Secondary operations
Work done after the press when the die cannot do it or when it costs less outside the die. Each one adds handling, and often an outside vendor and a transit leg, so list them on the RFQ.
- Deburring, tumbling and vibratory finishing
- Tapping and thread forming
- Spot, projection and laser welding
- Zinc, nickel and tin plating
- Passivation for stainless steel
- E-coat, powder coat and paint
- Heat treat for spring steel and stress relief
- Riveting and self-clinching fasteners
- Assembly and kitting
- Marking, cleaning and packaging
Frequently asked questions
How do I know which stamping process fits my part?
Four things decide it: annual volume, part size, draw depth and the number of features. High volume parts with many features usually fit a progressive die. Deep cups fit draw dies. Large parts that cannot stay on a strip fit transfer dies. Below a few thousand pieces a year, laser blanking and press brake forming often cost less than any die.
Can one part use more than one process?
Yes. A part can be blanked and formed in a progressive die, then tapped, welded and plated outside the press. Ask each quote to list every operation and who performs it.
Is stamping cheaper than CNC machining?
Per piece, yes at volume, because a die makes a part in one press stroke. The die has to be paid for first, so machining or laser cutting usually wins at low volume. The crossover is often between a few thousand and a few tens of thousands of pieces a year, depending on the part.
Keep reading
- Progressive Die vs Transfer Die vs Deep Draw: Which Process Fits Your Part
- Fourslide and Multislide Stamping: Which Parts It Makes Cheaper Than a Progressive Die
- Fine Blanking vs Conventional Blanking: When the Cleaner Edge Is Worth the Price
- Secondary Operations After Stamping: What to Specify and What It Costs
- Deep Drawn Parts: Design Rules That Keep Tooling Cost Down
- Stamping, CNC Machining or Laser Cutting: Which One Actually Fits Your Part
- Stamping press types and tonnage ranges
- Stamping materials and formability
Have a print ready? Get matched.
Send the print with material, thickness and annual volume. We match you with up to 3 stamping shops and reply within 24 business hours.