Die Maintenance Tracking: Hit Counters, Fields and Triggers

Key takeaways

• Track hits per die, not per press. A die moves between presses, and its wear travels with it.
• Every die needs three counters: lifetime hits, hits since last sharpen and hits since last PM.
• Use four maintenance triggers together: hit-based sharpening, hit-based PM, condition-based after a quality issue and calendar-based for idle dies.
• A die has a clear status lifecycle, from in press to quarantined. If nobody can see the status, the press shop finds out at the next die change.
• Record every repair in structured fields (defect code, station, amount ground, shim added, hours, parts) so you can measure hits between failures and repair hours per 100k hits.

What is die maintenance tracking?

Die maintenance tracking is the record of what every stamping die has done, what was done to it, and what it needs next.

It covers progressive, transfer and line dies, and it answers one practical question: can this die run the next order without a surprise?

A die wears with every stroke, gets sharpened, shimmed and repaired, and moves between presses and storage. So it needs its own record, not a note on the press.

The die record: fields every die needs

The master record describes the die itself and rarely changes. Values come from your die drawings and tryout sheets.

Two of these fields cause most planning errors when they are wrong: parts per hit and current shut height.

Parts per hit turns hits into parts, so a 2-out die with the field set to 1 doubles every forecast of the hits an order needs. Current shut height changes after every sharpening and shim, and the setter needs it at the next die change.

Hit and stroke counters: the data that drives everything

One press stroke with a die in it is one hit on that die. Each hit wears the cutting edges, the forming surfaces and the guiding parts a little.

Track three counters on every die.

Keep the counters on the die record. A counter that lives only on the press display is gone the moment the die comes out.

How hits are captured

There are two common sources, and most press shops use both.

• Press stroke counter via the PLC. The press control already counts strokes, usually from a crank angle or top dead centre signal. Reading that signal gives an exact count with no typing.
• Manual entry at die change. The setter reads the press counter when the die goes in and when it comes out, and writes the difference against the die ID.

The PLC count is accurate, but it counts press strokes. It only becomes die hits when you know which die was in the press between two die changes.

So the die change itself is the key event. Log the die ID, the press, the time and the counter reading at every change, whether you scan a label or type it in.

Why hits per die matter, not hits per press

A press counter tells you how hard the press worked. It says nothing about which die took those strokes.

Imagine a die that ran 40,000 hits on press 3 last week and 25,000 on press 5 this week. Each press shows a normal number, but the die has taken 65,000 hits and is past a 60,000 hit sharpening interval.

Maintenance triggers: four ways a die gets pulled

Use all four triggers, and record which one opened each work order.

Typical condition signals are burr height out of spec, a dimension drifting on the part check, slug pulling, a misfeed sensor stopping the press, or a crack on a formed flange.

The calendar trigger exists for dies that run rarely. A die that made 5,000 hits in a year never reaches its hit interval, but its springs, guides and surfaces still age in storage.

Set a warning level before each hit interval, for example at 80%, so the planner can schedule the pull. See also condition-based maintenance.

Die status lifecycle

At any moment, every die should be in exactly one status. The press shop and the toolroom should see the same one.

The rule that matters most: a die leaves "Awaiting tryout" only with an approved first-off part. A die that goes straight from the bench to production turns the first shift into the tryout.

Use "Quarantined" for anything unresolved, such as a suspected crack or a crash.

The repair and reconditioning record

Every visit to the toolroom gets a work order with structured fields. Free text alone ("sharpened die, fixed station") cannot be counted or compared.

The sharpening amount removed is the field most shops skip and later regret. Added up, it tells you how much grind stock is left on each section and when the section needs replacing.

Parts used should come out of the spare parts stock, so the stock level drops when a punch goes into a die. Our guide to spare parts inventory management covers min and max levels for die components.

Die repair priority matrix

The toolroom rarely has one die waiting. Rank the queue by two questions: when is the die needed, and how bad is the problem.

"Needed within 48 h" should come from the production schedule, not from whoever shouts loudest at the toolroom door.

If most of the queue is P1, the triggers are too late. Look at your maintenance backlog by die and by trigger to see why.

Worked example: planning the next sharpening

These numbers are an illustrative example, not a norm. Real sharpening intervals vary widely with the strip material, its thickness, the die steel, the clearance and the lubrication.

1. Hits per day

30 strokes per minute × 60 minutes = 1,800 hits per hour.

1,800 × 10 hours = 18,000 hits per day, which is 36,000 parts at 2 parts per hit.

2. Days between sharpenings

60,000 ÷ 18,000 = 3.3 production days between sharpenings.

The warning level arrives after 48,000 ÷ 18,000 = 2.7 days, which leaves only 12,000 hits (about 6.7 stroking hours, less than one shift) to plan the pull. On a die this fast, set the warning one production day early instead: 60,000 minus 18,000 = 42,000 hits.

3. When is this die due?

Remaining hits on Monday morning: 60,000 minus 21,000 = 39,000.

After Monday, 21,000 remain. After Tuesday, 3,000 remain, which is only 3,000 ÷ 1,800 = 1.7 hours of running on Wednesday.

4. Plan the maintenance window

The best window is the end of Tuesday's second shift. The die comes out at a planned change instead of stopping the press mid-shift on Wednesday.

If the toolroom needs 4 hours to sharpen, shim and reset the die, plus 1 hour of tryout, it can be back in "In storage, ready" before Wednesday's first shift ends.

5. Check the order against the interval

Suppose the open order is 90,000 parts. At 2 parts per hit that is 45,000 hits.

If this die sat in storage with 21,000 hits since its last sharpening, running the whole order would take it to 66,000, past the interval. Sharpen first, or split the run at a planned window.

6. Estimate remaining die life

Say the toolroom removes 0.10 mm per sharpening and a punch section has 2.0 mm of usable grind stock left (again, illustrative).

2.0 ÷ 0.10 = 20 more sharpenings, and 20 × 60,000 = 1.2 million hits before the section needs replacing. That only works if the amount removed is recorded every time.

KPIs for die maintenance

Measure die performance in hits, not calendar time.

Example for one die over a quarter: 1,200,000 hits, which at a 60,000 hit interval means 20 planned sharpenings plus 4 unplanned repairs. The toolroom booked 116 hours: 80 for sharpening at 4 hours each and 36 for the repairs.

Hits between failures = 1,200,000 ÷ 4 = 300,000. Repair hours per 100k hits = 116 ÷ 1,200,000 × 100,000 = 9.7 hours, of which 3.0 are unplanned.

If 22 of the 24 toolroom visits passed first-off on the first tryout, the first-off pass rate is 22 ÷ 24 = 91.7%.

Hits between failures is the die version of mean time between failures. Die-related downtime shows up in the press's availability, which is why OEE for stamping presses and die tracking belong together.

Common mistakes in die maintenance tracking

1. Counting per press

The press counter goes up, but no one knows which die took the hits. Log every die change.

2. Resetting the wrong counter

A setter resets "hits since last sharpen" after a PM visit where nothing was ground.

Reset each counter only when the matching work order is closed, and reset both when one visit covers sharpening and PM.

3. Skipping setup and tryout strokes

Tryout hits, inching and scrap strokes all wear the die. Leave them out and the die reaches its real interval before the counter does.

4. Free-text repair notes

"Fixed station 4" cannot be counted, sorted or compared.

Use defect codes, station IDs and numeric fields for amount ground and shim added.

5. Calendar-only PM on busy dies

A monthly PM on a die that runs 18,000 hits a day is far too late, and on a die that runs twice a year it is far too often.

Use hit-based triggers for running dies and calendar triggers only for idle ones.

6. Running without tryout approval

Under schedule pressure, a setter mounts a repaired die before quality has seen a part. Block the change to "In storage, ready" until the first-off part is signed, and log who released it.

Tryout takes press time, so fast die changes help: see our guides to quick die change and SMED.

How to set up die tracking in five steps

1. Register every die as its own asset with the fields above and a QR label on the die.
2. Define the counters and the starting values from your best current knowledge.
3. Connect the press stroke count or start manual counter readings at every die change.
4. Set the triggers: sharpening and PM intervals in hits, warning levels, calendar checks for idle dies.
5. Review monthly: hits between failures, repair hours per 100k hits and the dies with the most downtime.

Start with the ten dies that cause the most downtime. For choosing a system, see tool and die maintenance software and our comparison of the best maintenance software for stamping dies.

How Fabrico helps

Fabrico is an OEE platform with a full CMMS built in.

It connects to the press through PLC connectivity, so it can count strokes and calculate OEE per press in real time, including downtime and short stops.

You can register each die as its own asset with a QR code, so a toolmaker scans the die to open its history, documents and open work orders on the mobile app or the web.

Your team builds preventive plans from recurring templates and conditional tasks, and plans each sharpening from the hits it logs at every die change. The work orders record the spare parts consumed, with min and max stock levels for punches, springs and inserts.

Fabrico does not assign press strokes to a die on its own, and it does not open work orders when a counter reaches its interval. Those steps stay with your team.

The AI assistant answers questions about a press or a die's repair history in plain language.

Want to see die and press data in one place? Book a 30 minute demo with a Fabrico consultant, no commitment, or contact us with your questions.