Punches for Metal Stamping Dies
A punch does the cutting. Everything else in a stamping die exists to hold it on location, strip the scrap and keep it sharp.
Punch selection comes down to retention style, head type, and whether the die runs standard or metric. Get the retention wrong and the punch will pull out of the retainer under load.
Start with the function
Retention style
BallLock punches lock into the retainer on a ball detent and pull straight out; conventional headed punches seat in a counterbore. Which you run depends on how often the die is set up.
Punch systems
Danly covers the working systems - TuffPunch, Kommercial, VersaPlus and Versatile in inch and metric - with Porter and Unipunch for conventional and unitized tooling.
Sleeves and in-die tapping
Ejector sleeves push thin-wall parts and deep bosses off a core without marking them. In-die tapping cuts threads in the press instead of a second operation.
What to look for
BallLock punches. The punch locates on a ball detent and comes straight out of the retainer, which is the whole point: changeover without stripping the plate stack.
Porter punches. The standard heavy-duty headed punch line for conventional retention - a solid workhorse where changeover speed is not the problem being solved.
Unipunch. Unitized tooling: punch, die and stripper built as one self-contained unit for notching and sheet-metal work away from a full die.
Ejector sleeves. Nitrided hot-work steel with a working surface at 65-74 Rc over a tough core. Thin-wall sleeves for thin-wall parts, D-head sleeves where the sleeve must not rotate, and oversized sleeves for a worn bore or an oversized core. Sleeves are sized by ID (fits the core), OD (fits the plate bore) and overall length - PCS alone stocks over 130 standard sleeves with IDs from 3/32 in. to 3/4 in. and lengths up to 14 in., in inch, metric DIN and metric JIS.
In-die tapping. Threads formed in the press, which removes a secondary operation from the process.
