Die Tryout Process: Steps, Documentation and First Article Approval

Die tryout is the phase that separates a CAD concept from a production-capable tool. No matter how rigorous the simulation or how experienced the die designer, the stamping process is not validated until metal is actually formed under controlled conditions and measured against the part drawing. Get the tryout wrong — skip documentation steps, accept cosmetically passing parts without checking dimensions, or rush FAI sign-off — and you will pay the price in production with chronic rework, unplanned downtime, and customer rejections.

This guide walks through the complete die tryout process: preparation before the first hit, the structured tryout sequence, measurement and adjustment cycles, full documentation requirements, and what first article inspection (FAI) approval actually demands. The content applies to progressive dies, transfer dies, compound dies, and deep drawing tools across automotive, appliance, and industrial part categories.

---

What Die Tryout Is — and What It Is Not

Die tryout is a systematic engineering process to bring a new or modified stamping die from build completion to production-ready status. It is not a “let’s see what happens” session. Every run, every adjustment, and every measured part is documented because the tryout record becomes the baseline against which future deviations are judged.

Three distinct outcomes must be achieved before a die can be released for production:

1. Dimensional conformance — all features on the part drawing, with their GD&T callouts, fall within tolerance at a statistically valid sample size.
2. Process window documentation — the combination of press parameters (tonnage, stroke rate, lubrication type and volume, feeder settings, die height) that consistently produces conforming parts is recorded and locked.
3. Die condition baseline — witness marks, shim records, spring loads, and sensor calibration values are documented so that any future deviation from this baseline can be detected and corrected.

If any of these three pillars is missing, the die has not passed tryout — regardless of what the parts look like on the surface.

---

Phase 1: Pre-Tryout Preparation

Arriving at the press without preparation wastes hours. Everything below should be completed before the die is loaded.

Drawing and Data Package Review

Pull the current-revision part drawing, the die design drawings, and the CAD/CAM data package. Verify that:

• The part drawing revision matches the die design revision.
• All GD&T datum references (typically A/B/C or three mutually perpendicular planes) are physically established in the die — the same datums must appear in the CMM fixture.
• Material specification, thickness, and coil width tolerance are confirmed with the incoming material certification.
• Any simulation output (AutoForm, PAM-STAMP, or equivalent) is reviewed for predicted problem zones: thinning, wrinkling, springback, and draw depth limitations.

Do not proceed if revision mismatches exist. A single-revision discrepancy is enough to invalidate FAI.

Material Certification Check

For the tryout material, collect the material test report (MTR) and verify:

Property	Typical Requirement	Check Against
Yield strength (Rp0.2)	±15% of nominal	Drawing spec or material standard
Tensile strength (Rm)	Within material grade range	EN 10130, ASTM A1008, JIS G3141
Elongation (A80)	≥ drawing minimum	MTR value
r-value (Lankford)	Specified if drawing critical	Material cert or lab test
n-value (strain hardening exponent)	For deep drawing	Formability requirement
Thickness	t ± tolerance per drawing	Measured at 3+ coil locations

Using off-spec material during tryout contaminates the process window data. If you use material with yield strength 60 MPa above nominal, the springback, blank holder force requirements, and tool wear pattern will all shift in production when standard material is used.

Press Preparation

Confirm the tryout press meets the die design specification:

• Bed size — die must fit with minimum 150 mm clearance on all sides.
• Rated tonnage at the specified tonnage height — this is critical. A 400-ton press may only be rated at 300 tons at 25 mm above BDC; if the die works at 30 mm snap-through, you need the full 400 tons available at that point.
• Shut height (closed height) — press shut height range must accommodate the die’s required closed height with sufficient adjustment range above and below.
• Stroke length — must allow the die to fully open for part and scrap removal without interference.
• Slide parallelism — measure at four corners with a dial indicator. Deviation > 0.05 mm/m indicates a press alignment problem that will corrupt tryout data.

Record all press settings in the tryout log before loading the die.

Safety and Tooling Equipment

• Calibrated tonnage monitoring system installed and zeroed.
• Die protection sensor wiring diagram confirmed.
• Lifting equipment rated for die weight (include die cushion and hardware).
• Tryout log forms, micrometer, caliper, part check fixtures, and marking dye ready at the press.

---

Phase 2: Die Loading and Initial Setup

Mounting the Die

Load the die per the standard die change procedure. Set the initial die height 5–10 mm above the theoretical closed height. This safety margin prevents a crash if the die height calculation contains an error.

Check the following after mounting:

• Upper die bolts torqued to specification (record torque value in log).
• Lower die bolts torqued to specification.
• Nitrogen gas spring connections made and pressure verified (if applicable).
• Die cushion pressure set to minimum design value.
• Feeder advance, pilot engagement, and scrap chute clearance confirmed.
• Safety blocks removed from die interior.

Witness Marking

Before the first hit, apply layout dye (Dykem or equivalent) to all punch faces, trimming edges, and forming surfaces. This initial witness mark shows contact pattern and highlights high spots before the die is broken in.

---

Phase 3: First Hit Sequence

Inching to BDC

Use manual inch mode to bring the slide to BDC slowly. Stop every 10–15 mm of slide travel and inspect for interferences. Do not proceed to BDC at speed until a complete inch-through confirms zero interference.

At BDC in inch mode:

1. Measure the actual die closed height with a depth gauge or feeler gauge at four corners of the upper/lower die interface. Record all four values.
2. Compare to theoretical closed height. A variance > 0.3 mm at any corner indicates an assembly problem — do not run.
3. Inspect pilot engagement depth. Pilots must fully seat before the punch contacts the strip.

First Blank Run

Run 3–5 single-stroke hits at the minimum viable tonnage (MV tonnage = 80% of expected forming tonnage based on simulation). Inspect every part for:

• Splits or necking (excessive tension)
• Wrinkles (insufficient blank holder force or incorrect draw radius)
• Rollover on cut edges (incorrect die clearance)
• Part ejection — does the part release cleanly, or does it stick?
• Scrap evacuation — does scrap route to the chute without bridging?

Mark each part with a sequential number and the hit count for traceability.

---

Phase 4: Systematic Die Adjustment

This is the technical core of tryout. Each adjustment must be documented before being made, and parts must be saved before and after each change so the effect can be isolated.

Common Adjustment Sequence

Step 1: Establish die closure and set pressure

Before correcting part geometry, confirm the die closes correctly. Check:

• Die height: adjust in 0.1 mm increments, never more than 0.5 mm per step.
• Blank holder force (BHF): start at the minimum value from simulation, increase in 10% increments.
• Die cushion pressure: verify uniform pressure across cushion pins with a pressure-check plate.

Step 2: Address splits and thinning

If splitting occurs, measure thinning percentage at the failure zone:

$\text{Thinning \%} = \frac{t_0 - t_f}{t_0} \times 100$

Where:

• t₀ = original blank thickness (mm)
• t₁ = measured thinned thickness at failure zone (mm)

Acceptable thinning limit for most materials is 20–25%. At 25–30%, the part is marginal. Above 30%, splitting is almost certain.

Corrective actions for splitting, in order of preference:

1. Reduce blank holder force (reduces radial tension).
2. Increase draw radius (die and/or punch radius, not less than 4t for steel).
3. Increase lubrication at the problem zone.
4. Modify blank shape to reduce blank holddown area in the high-tension region.
5. Reduce punch speed (for servo press) or add a dwell at BDC.

Step 3: Address wrinkling

Wrinkle severity is classified on a 1–4 scale:

• Grade 1: slight surface waviness, typically within surface finish spec
• Grade 2: visible wrinkles that may be flattened by subsequent operations
• Grade 3: wrinkles that cannot be eliminated downstream — part is scrap
• Grade 4: severe wrinkling causing material pile-up and potential tool damage

Corrective actions:

1. Increase blank holder force (in 10% increments).
2. Reduce draw radius at the wrinkle initiation point.
3. Add draw beads or increase draw bead height.
4. Verify material properties — high r-value materials resist thinning but may need higher BHF.

Step 4: Springback correction

Springback in bending follows:

$\frac{R_i}{R_f} = \frac{R_i \cdot \sigma_y}{E \cdot t} \cdot (3 - 2 \cdot \frac{R_f + t/2}{R_i + t/2})$

This simplified relationship (Sachs formula) shows that springback ratio (Rᵢ/R_f) increases with yield strength (σ_y) and bend radius (R_i), and decreases with elastic modulus (E) and material thickness (t).

In practice, springback angles are measured from the tryout part and compensated by:

• Overbending: tool angle reduced by the measured springback angle (e.g., if 2° springback observed, bend to 88° for a 90° feature).
• Bottoming / coining: apply high local pressure at BDC to eliminate elastic recovery in critical zones.
• Sidewall curl correction: adjust punch and die radii asymmetrically.

Document the springback measurement method, the measurement points, and the compensation values applied to the die.

Step 5: Trimming and piercing quality

Check cut edge quality:

• Burnish zone depth = 30–50% of stock thickness (normal)
• Fracture zone = remaining material (rough but acceptable)
• Rollover depth < 10% of stock thickness
• Burr height < 0.15 mm for general stamping; < 0.05 mm for assembly-critical edges

If burr height is excessive, check:

• Punch-to-die clearance (too large → excessive burr; too small → chipping)
• Punch sharpness — regrind if radius > 0.05 mm
• Die clearance non-uniformity — check concentricity with an optical comparator or CMM

Adjustment Documentation Table

For every adjustment made, record in the tryout log:

Hit #	Adjustment Made	Parameter Before	Parameter After	Parts Saved	Observed Result
12	BHF increase	80 kN	95 kN	#10–12	Wrinkle reduced to Grade 1
18	Draw radius polish	R6 rough	R6 polished, Ra 0.4	#15–18	No change to split
24	Die height decrease	285.2 mm	284.8 mm	#20–24	Burnish depth improved to 40%

This table is a legal record. Do not skip it “because you remember what you did.”

---

Phase 5: Dimensional Measurement and CMM Correlation

Once the part is visually and functionally acceptable, every dimension on the drawing must be measured. This is not optional.

CMM Fixturing Requirements

The CMM fixture must constrain the part in the same datum scheme defined on the drawing. For sheet metal parts, this typically means:

• Primary datum (A): three-point contact on the major surface, constraining Z-translation and X/Y rotation.
• Secondary datum (B): two-point contact on a precision surface or locating pin, constraining one translation and one rotation.
• Tertiary datum (C): one-point or surface contact, constraining the final degree of freedom.

A poorly designed fixture that allows the part to deform under clamping loads will produce false CMM data. Clamping forces must be defined and documented.

Measurement Sample Size

For tryout sign-off:

• Minimum 5 consecutive parts measured at all critical dimensions.
• All parts must be within drawing tolerance.
• For FAI, AIAG/VDA PPAP Level 3 typically requires 30 consecutive parts from a short production run.

Do not cherry-pick measured parts. Consecutively numbered parts from a stable process run — no sorting, no re-hits.

Dimensional Report Format

Organize the dimensional report by balloon number from the drawing:

Balloon	Feature Description	Nominal	Tolerance	Measured (Avg of 5)	Deviation	Pass/Fail
1	Overall length	285.0 mm	±0.3	285.05 mm	+0.05	PASS
7	Hole Ø12 position X	145.0 mm	±0.2	145.18 mm	+0.18	PASS
12	Flange angle	90°	±0.5°	91.2°	+1.2°	FAIL
18	Edge-to-edge distance	62.5 mm	±0.15	62.51 mm	+0.01	PASS

Any FAIL triggers a documented corrective action and a re-measurement cycle.

---

Phase 6: Process Window Documentation

A conforming part from a single process setting is not enough. The process window defines the range of parameter variation that still produces conforming parts.

Minimum Parameters to Document

Press parameters:

• Slide shut height (mm) — record actual, not nominal
• Stroke rate (SPM) at production speed
• Press tonnage at BDC (from tonnage monitor — max allowable = 80% of press rated tonnage)
• Die cushion pressure (bar or kN per pin)

Die parameters:

• Die height (closed height, mm, four-corner values)
• Nitrogen spring pre-load (if applicable) — pressure at open and at closed height
• Draw bead engagement depth (if adjustable)
• Shim stack records (all shims by location, material, and thickness)

Material parameters:

• Material grade, thickness, and heat number used during sign-off run
• Coil width (actual measured value)
• Lubrication type, concentration, and application rate (g/m² or L/hr)
• Strip tension in feeder (if measurable)

Environmental:

• Ambient temperature at time of sign-off (affects lubricant viscosity)

---

First Article Inspection (FAI): Requirements and Documentation

FAI is the formal quality event that transfers the die from the tryout team to production. It is a customer-facing document package, not an internal memo.

FAI Package Contents (PPAP Level 3 Basis)

1. Design records — current revision drawing, math data (3D model), and engineering change history.
2. Engineering change documentation — all deviations from original design, with customer approval reference numbers.
3. Customer engineering approval — signed or emailed written approval for any interim deviations.
4. Design FMEA (if customer-designed) or Process FMEA — current revision, with all actions closed.
5. Process flow diagram — sequence from blank to finished stamped part.
6. Control plan — preliminary (for tryout) and production control plan, with inspection frequency, methods, and reaction plans.
7. Measurement system analysis (MSA) — Gage R&R study for all critical measurement methods. Acceptable threshold: %R&R < 10% (excellent), 10–30% (conditionally acceptable with customer approval).
8. Dimensional results — 30-piece report (balloon-numbered, all dimensions, all within tolerance or with approved deviation).
9. Material/performance test results — material MTR, any performance tests (corrosion, plating adhesion, hardness).
10. Initial process capability study — preliminary Cpk (minimum Ppk ≥ 1.33 for all critical characteristics; Ppk ≥ 1.67 for safety or functional critical).
11. Sample production parts — number and labeling per customer requirement (typically 3–5 labeled samples).
12. Records of compliance — regulatory and safety compliance documentation.
13. Part submission warrant (PSW) — signed by authorized supplier representative.

Cpk / Ppk Calculation

For each critical characteristic, calculate:

$P_{pk} = \min\left(\frac{USL - \bar{X}}{3s}, \frac{\bar{X} - LSL}{3s}\right)$

Where:

• USL = upper specification limit
• LSL = lower specification limit
• X̄ = sample mean (30 parts)
• s = sample standard deviation

A Ppk of 1.33 means the process mean is at minimum 4 standard deviations away from the nearest specification limit. For new processes, 1.67 is the target.

If Ppk < 1.33, the part cannot receive unconditional FAI approval. Options:

• Identify and eliminate the assignable cause of variation.
• Apply 100% inspection at production with a documented deviation until Cpk improves.
• Request a temporary deviation from the customer with a corrective action plan and timeline.

---

Common Tryout Failure Modes

The following are the most frequent reasons die tryouts fail or take significantly longer than planned:

1. Inadequate blank size or shape The blank development in simulation used incorrect material properties. The actual blank either draws in too fast (creating wrinkles) or runs out of material too early (causing splits). Correction: re-develop blank using actual r-value from MTR and re-simulate.

2. Revision mismatch between die and drawing The die was built to revision B; the drawing is now at revision D. Three weeks of tryout produces parts to the wrong geometry. Prevention: formal revision control gate before tryout approval.

3. Press not matched to die requirements Die requires 350-ton force at 30 mm above BDC; the tryout press is rated at 350 tons at 6 mm above BDC. The actual available tonnage is insufficient, causing incomplete forming. Always plot the die’s force-displacement curve against the press’s available tonnage curve.

4. CMM fixture not qualified Fixture allows part to sag or deform under clamping. CMM results show multiple PASS results that are actually FAIL — discovered only when the customer measures with their own fixture. Prevention: validate the fixture with a reference artifact before the measurement run.

5. Springback not stabilized before measurement Sheet metal springback can change over 24–72 hours after forming due to stress relaxation, particularly in AHSS and stainless grades. Measure parts at least 4 hours post-forming; for AHSS grades, 24 hours is recommended.

6. Tryout material properties outside nominal Tryout run on soft (low yield) material passes; production material at nominal yield fails springback spec. Always document the MTR properties and flag if tryout material is outside ±10% of nominal yield strength.

7. Missing shim or spring records The die is signed off with undocumented shims under the blank holder. When the die returns from maintenance (after regrind or repair), the shims are not restored correctly. Parts are immediately out of specification. Prevention: mandatory shim map as part of sign-off documentation.

8. Process window too narrow to be practical The die only makes conforming parts within a 3-bar range of die cushion pressure. Practical production requires a ±5-bar range minimum. Tryout must verify robust process window, not just a single-point conforming run.

---

Industry Applications: Die Tryout Across Sectors

Automotive Body Panels

Panel dies (door outers, hoods, trunk lids) are among the most complex tryout programs. A typical outer panel die:

• Requires 6–12 weeks of tryout
• Involves 500–2,000+ total hits before sign-off
• Includes Class A surface inspection (oil-stone check, reflection check) in addition to dimensional CMM
• Springback compensation may require 3–5 geometry iterations with customer design sign-off at each step

The industry standard for automotive FAI is the AIAG PPAP manual (4th edition). PPAP Level 3 is the default unless otherwise specified by the OEM.

Home Appliance Components

Appliance stampings (washing machine tubs, refrigerator liners, compressor shells) prioritize:

• Tightness of tolerances on hole patterns for assembly
• Surface appearance (visible or semi-visible parts)
• High-volume process stability (Cpk targets often ≥ 1.67 for critical features)

Tryout programs are typically 2–4 weeks, with 30-piece FAI at rated production speed (not reduced-speed tryout hits).

Industrial and Structural Brackets

Structural stampings allow more aggressive tryout — dimensional tolerances are wider (often ±0.5 mm on non-critical features), and surface appearance is secondary. However, functional features (hole locations for fasteners, mating surfaces) carry tight tolerances and must be validated against assembly fixtures, not just the part drawing.

Electrical Contact Stampings

Fine-blanked or precision-stamped contacts require:

• Cut edge quality inspection at 20x magnification
• Functional electrical testing of contact resistance
• Plating adhesion tests on post-production samples

FAI for contacts often includes Gage R&R on the precision measurement systems (optical comparators, vision systems) as well as the physical parts.

---

Frequently Asked Questions About Die Tryout

Q: How many hits should a die tryout take? There is no universal answer. Simple progressive die for a flat bracket: 50–200 hits. Complex automotive deep draw die: 1,000–5,000 hits over multiple weeks with geometry modifications. The tryout is done when the dimensional report passes and the process window is documented — not based on hit count.

Q: Can tryout and production be run on different presses? Yes, but only if both presses have identical or very similar specifications (rated tonnage, shut height, slide dynamics). Process parameters are press-specific. If the production press is different from the tryout press, a re-validation run at the production press is required before FAI sign-off.

Q: What is the difference between die tryout and die prove-out? The terms are often used interchangeably, but in formal production programs, “tryout” refers to the iterative development phase (making adjustments), while “prove-out” or “run-at-rate” refers to a final production-speed run to demonstrate process stability before FAI sign-off. Both are required for a complete PPAP submission.

Q: Who signs off on FAI — the die maker or the part producer? The Part Submission Warrant (PSW) is signed by the production supplier (the company that will manufacture the part in production). The die maker may have a separate completion report, but the PSW is always the production supplier’s responsibility.

Q: What happens if FAI is submitted with a dimensional FAIL? A deviation request (or engineering change request) must be submitted to the customer with the specific out-of-tolerance condition identified, a root cause analysis, a proposed correction plan, and a target date. The customer either approves a temporary deviation (allowing limited production while the die is corrected) or holds the program until the die conforms.

Q: Is it acceptable to submit FAI on tryout parts, not production-speed parts? No. FAI parts must be taken from a minimum 300-piece production run at production tooling, conditions, and rated speed. Using slow-speed tryout hits is a documentation fraud that will be discovered when production parts do not match FAI samples.

Q: How should tryout be handled for a modified (repaired or reground) die? Any change that affects part geometry — regrinding punch faces, modifying radii, replacing inserts — requires a re-tryout at the affected features and a new dimensional report. If the change is minor (cosmetic polishing, shim adjustment not affecting closed height), a deviation-based update to the existing tryout record is acceptable with engineering sign-off.

---

JSON-LD FAQ Schema

{
  "@context": "https://schema.org",
  "@type": "FAQPage",
  "mainEntity": [
    {
      "@type": "Question",
      "name": "How many hits should a die tryout take?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "There is no universal answer. Simple progressive dies may need 50–200 hits; complex automotive deep draw dies may require 1,000–5,000 hits over multiple weeks with geometry modifications. Tryout ends when the dimensional report passes and the process window is documented."
      }
    },
    {
      "@type": "Question",
      "name": "Can tryout and production be run on different presses?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Yes, but only on presses with identical specifications. Process parameters are press-specific. If the production press differs from the tryout press, a re-validation run at the production press is required before FAI sign-off."
      }
    },
    {
      "@type": "Question",
      "name": "What is the difference between die tryout and die prove-out?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Tryout refers to the iterative development phase where adjustments are made. Prove-out or run-at-rate is the final production-speed run demonstrating process stability before FAI sign-off. Both are required for PPAP."
      }
    },
    {
      "@type": "Question",
      "name": "Who signs off on first article inspection (FAI)?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "The Part Submission Warrant (PSW) is always signed by the production supplier — the company that will manufacture the part in production — not the die maker."
      }
    },
    {
      "@type": "Question",
      "name": "What happens if FAI is submitted with a dimensional failure?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "A deviation request must be submitted to the customer identifying the out-of-tolerance condition, root cause, correction plan, and target date. The customer either approves a temporary deviation or holds the program."
      }
    },
    {
      "@type": "Question",
      "name": "Is it acceptable to submit FAI on tryout parts rather than production-speed parts?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "No. FAI parts must come from a minimum 300-piece production run at production tooling, conditions, and rated speed. Using slow-speed tryout hits is a documentation error that violates PPAP requirements."
      }
    }
  ]
}

---

Conclusion

Die tryout is engineering work, not guesswork. The difference between a four-week tryout and a sixteen-week tryout is almost always the quality of preparation, the rigor of documentation during adjustments, and the discipline to not skip measurement steps when a part “looks good.”

Key takeaways:

• Pre-tryout preparation — press verification, drawing review, material certification — eliminates the most common causes of lost time.
• Every hit, every adjustment, and every measured part gets logged. No exceptions.
• Springback measurement must occur at the correct time-after-forming interval for the material grade.
• FAI sign-off requires 30 conforming consecutive parts at production speed, a complete PPAP package, and Ppk ≥ 1.33 on all critical characteristics.
• Process window documentation (not just a single conforming hit) is what makes a die production-ready.

A well-executed die tryout produces a tool that runs predictably from the first production shift. Shortcuts in tryout are always more expensive than the time they appear to save.

---

How Demirezen Engineering Can Help

At Demirezen Engineering, we manage die tryout programs from initial press selection through FAI submission. Our experience covers progressive dies, deep draw tooling, transfer dies, and compound dies across automotive, appliance, and industrial sectors.

If you need technical support for a difficult tryout — persistent splits, springback beyond compensation range, dimensional instability, or a stalled PPAP — contact us directly:

• WhatsApp: +90 543 341 6183
• Website: demirezenengineering.com

We respond within one business day.

---

Internal Link Suggestions

• Transfer Die vs Progressive Die: Decision Framework for High-Volume Stamping
• Blanking Die Clearance Calculation by Material Type and Thickness
• Springback in Sheet Metal Forming: Causes, Measurement and Compensation Methods
• Progressive Die Strip Layout: Step Calculation, Pilots and Carrier Design
• Forming Limit Diagram (FLD): How to Read, Generate and Apply in Production

---

External Reference Suggestions

• AIAG PPAP Manual, 4th Edition — Production Part Approval Process, Automotive Industry Action Group (aiag.org)
• ISO 9001:2015 — Quality Management Systems Requirements, International Organization for Standardization (iso.org)
• SME (Society of Manufacturing Engineers) — Die Design Fundamentals — Reference text for die construction and validation, available via sme.org

---

Suggested Images and Diagrams

1. Die tryout phase flowchart — Swim-lane diagram showing Pre-Tryout → Die Loading → First Hit → Adjustment Cycle → Dimensional Measurement → FAI. ALT text: “Die tryout process flow chart from preparation to first article approval”

2. Tonnage-displacement curve overlay — Graph showing press available tonnage curve vs. die required force curve at each millimeter of stroke. ALT text: “Press tonnage curve vs die required tonnage plotted against stroke position”

3. Thinning measurement map — Top-down view of a drawn part with color-coded thinning percentage zones overlaid on the blank shape. ALT text: “Sheet metal thinning percentage map from die tryout measurements”

4. CMM fixture setup photo or diagram — Showing three-datum constraint scheme with the part located and clamped per drawing datum reference frame. ALT text: “CMM fixture for stamped sheet metal part showing ABC datum constraint”

5. Tryout adjustment log excerpt — Sample page from a completed tryout log showing hit numbers, adjustments, and observed results. ALT text: “Die tryout adjustment log documenting parameter changes and results”