Deep draw, stretch forming and compound forming tools for complex geometries that need tight tolerance control.
Forming is where sheet metal stops behaving predictably. Springback, thinning at the draw radius and wrinkling at the flange are all decided by the punch and die radii, the blank holder force and the draw ratio — not by the press.
We build draw dies, restrike tools and compound forming tools designed around the material behaviour, and we say up front where a component will need more than one draw stage.
What we build
Specification
| Draw punch and die | D2 / HCHCr, hardened and polished on drawing surfaces |
|---|---|
| Draw radii | Sized against thickness and grade to control thinning |
| Blank holder | Spring or nitrogen cylinder, force set against draw ratio |
| Surface finish | Drawing faces polished — a ground finish alone will score |
| Springback | Compensated in the tool, confirmed at tryout |
| Stage count | Calculated from draw ratio, not assumed |
Process
Questions
Usually the draw ratio is too aggressive for a single stage, the punch radius is too tight, or blank holder force is too high and the material cannot feed in. It is a tool and process question, not a material defect — send us the part and the tool details and we will tell you which it is.
It can be compensated for, not eliminated. We overbend or overform in the tool and correct against measured first-off samples at tryout. Springback also shifts with material batch, so a restrike stage is sometimes the more stable answer.
That comes out of the draw ratio between blank diameter and punch diameter, and the material. We calculate it at the feasibility stage rather than discovering it during tryout.
More from the tool room
Blanking, piercing, forming, bending, compound and progressive dies engineered for precision sheet-metal work at production volume.
View capability →Custom machining, welding, assembly and inspection fixtures built for repeatability across automotive and industrial production.
View capability →Injection mould tooling for plastic components, designed for dimensional accuracy and long production life.
View capability →Inspection gauges, go/no-go gauges, checking fixtures and special-purpose machines built to your quality-control requirements.
View capability →Custom precision machining, component development and prototype manufacturing for one-off and low-volume engineering requirements.
View capability →A real engineer reads it — not an autoresponder. We will tell you whether the tool can be built as drawn, and what we would change to bring the cost down.