# Adjustable bench inspection fixture — LIGHT review

A proposed manually adjusted fixture for positioning a de-energized sample during bench inspection.

**Kind:** hardware · **Investigation:** Adjustable bench inspection fixture · **Composed:** 2026-10-01T21:14:55.266Z · **Model:** openai gpt-6-sol

## 1. Problem space

**Who:** A person conducting a proposed bench inspection.

**Pain:** A small sample may need positioning and visual access; repeatability and holding performance have not been established.

**Context:** Fictional teaching case. The supplied mechanical parameters are design constraints, not measured geometry or evidence of a working fixture.

Evidence: `fixture-question` Hold the sample for inspection; `fixture-dimensions` Fixed dimensions and interfaces; `fixture-concept` Three modules, twenty proposed parts

## 2. Solution idea

Review the locked multipart fixture as structural supports, manual adjustment interfaces, and assembly with proposed checks. A separate deterministic CAD builder may later construct and measure geometry.

**Differentiators**

- Manual adjustment only
- Explicit review of coordinate conflicts before any claim of usable travel

**Non-goals**

- Manufacturing approval
- Holding-force or repeatability claims
- Motorization or machine control
- Physical testing in this package

## 3. Concept

**User journey**

1. Review interfaces and the proposed motion envelope before assembly planning.
2. Plan the base, supports, guides, jaws and pads without assuming missing passages or attachments.
3. Plan the screw, nut and knob interfaces; defer physical assembly and checks until conflicts are resolved.

**Success criteria**

- The locked parameter contract is reproduced without alteration.
- The 78 mm nominal opening is identified as conditional on inward-facing pads.
- The 60 mm opening-direction conflict and unresolved interfaces are recorded rather than treated as usable motion.

## 4. Data

**Entities**

| Entity | Fields | Source |
| --- | --- | --- |
| ParameterContract | schema, coordinateSystem, parameters, limitations | Supplied mechanicalDesign; locked input, not compiled CAD |
| InterfaceFinding | subassembly, supplied envelope, inferred overlap, unresolved interface, proposed later check | Reasoning from fixture-dimensions and the supplied contract |
| PartProposal | part name, proposed quantity, specified dimensions, allocation uncertainty | fixture-concept and supplied contract; bushing allocation remains inferred |

**Evidence used as data**

| Evidence | Use |
| --- | --- |
| `fixture-question` Hold the sample for inspection | Bound the fictional use case and prohibit performance claims. |
| `fixture-dimensions` Fixed dimensions and interfaces | Identify supplied coordinates and proposed opening, travel and clearance. |
| `fixture-concept` Three modules, twenty proposed parts | Bound modules and the proposed multipart count. |

## 5. Architecture

A mechanical planning package, not an implemented device or CAD assembly. The locked contract governs later deterministic CAD work; this review records conflicts without modifying it.

**Components**

| Component | Responsibility | Technology |
| --- | --- | --- |
| Structural group | Base, feet, supports, rods, jaws, pads and proposed guide interfaces. | Mechanical parts; CAD source deferred |
| Manual adjustment group | Proposed lead screw, nut and hand-knob interfaces. | Manual mechanical mechanism; thread and retention unspecified |
| Review record | Assembly order, interface questions and proposed CAD and bench checks. | Versioned planning text; no deployed software |

**Interfaces**

| From | To | Protocol | Purpose |
| --- | --- | --- | --- |
| Structural group | Manual adjustment group | Physical screw, nut and jaw interface, unresolved | Identify passages, restraint and retention without assuming they exist. |
| Review record | Separate CAD builder | Locked mechanicalDesign JSON | Supply unchanged parameters for later construction and geometric review. |

**Deployment:** None. CAD/source generation, geometric measurements, fabrication and physical checks are separate later operations.

## 6. Modules

| Id | Module | Purpose | Depends on |
| --- | --- | --- | --- |
| m1 | Structural and support parts | Bound the base, supports, feet, guides, jaws, pads and bushing interfaces. | — |
| m2 | Manual jaw adjustment and interfaces | Review screw, nut, knob, opening and travel without asserting operability. | m1 |
| m3 | Assembly and proposed bench checks | Reconcile named parts and plan conditional CAD and non-destructive checks. | m1, m2 |

## 7. Build waves

### Wave 1 · Wave 1 — establish structural interfaces (sequential)

Document supplied envelopes and unresolved support, guide and jaw interfaces.

Modules: m1

### Wave 2 · Wave 2 — adjustment, then checks (sequential)

Review M2 before M3; stop at conflicts and do not infer a working assembly.

Modules: m2, m3

## 8. PRDs

### m1

**S1 · Map base, feet and end supports**

- Record supplied envelopes and coordinate origin; mark attachment and foot placement interfaces unspecified.

**S2 · Map rods, jaws, pads and bushings**

- Record rod axes through jaw envelopes; mark passages, bushing allocation, seating and retention unresolved.

### m2

**S3 · Review screw, nut and knob**

- Record screw-envelope crossings and missing passages, thread, nut restraint, axial retention and knob coupling.

**S4 · Review opening and travel**

- Show conditional 78 mm pad opening and both proposed 60 mm endpoints; flag the 8 mm opening-end support overlap.

### m3

**S5 · Reconcile parts and assembly order**

- List only named parts; label four bushings an inferred allocation and do not invent fastening hardware.

**S6 · Plan conditional checks**

- Separate later CAD interference review from unperformed, non-destructive visual access and unloaded manual checks.

## 9. Bill of materials

| Part | Qty | Specification | Est. cost | Supplier hint |
| --- | --- | --- | --- | --- |
| Base | 1 | 240 × 180 × 10 mm | Not estimated | Material and fabrication unspecified |
| Guide rod | 2 | Ø10 × 200 mm; proposed axes Y45/135, Z32 | Not estimated | Material and sourcing unspecified |
| End support | 2 | 16 × 140 × 32 mm | Not estimated | Passages and attachment unspecified |
| Jaw | 2 | Fixed and moving; each 18 × 120 × 43 mm | Not estimated | Guidance and attachments unspecified |
| Pad | 2 | Each 3 × 100 × 30 mm; inward placement assumed for stated opening | Not estimated | Material and attachment unspecified |
| Bushing | 4 | Inferred quantity, not locked; Ø16 OD, Ø10.4 bore, 18 mm length | Not estimated | Allocation, fit and retention unresolved |
| Lead screw | 1 | Ø8 nominal × 220 mm; thread unspecified | Not estimated | Bearing and axial retention unresolved |
| Nut | 1 | Ø18 OD, Ø8.4 nominal bore, 14 mm length; thread unspecified | Not estimated | Engagement and anti-rotation unresolved |
| Hand knob | 1 | Ø32 × 10 mm | Not estimated | Screw coupling unresolved |
| Foot | 4 | Ø22 × 12 mm | Not estimated | Attachment and vertical placement unresolved |

## 10. Geometry

Each part below gets parametric source, STEP/STL exports and dimensioned drawings in `cad/<part>/` once its geometry is generated; the runner checks the measured envelope and mass against these values.

| Id | Part | Kind | Envelope (mm) | Material | Mass (g) | Tool | Module | BOM part |
| --- | --- | --- | --- | --- | --- | --- | --- | --- |
| p1 | Base | mechanical | 240 × 180 × 10 | Unspecified |  | auto | m1 | Base |
| p2 | Guide rod | mechanical | 200 × 10 × 10 | Unspecified |  | auto | m1 | Guide rod |
| p3 | End support | mechanical | 16 × 140 × 32 | Unspecified |  | auto | m1 | End support |
| p4 | Fixed jaw | mechanical | 18 × 120 × 43 | Unspecified |  | auto | m1 | Jaw |
| p5 | Moving jaw | mechanical | 18 × 120 × 43 | Unspecified |  | auto | m1 | Jaw |
| p6 | Pad | mechanical | 3 × 100 × 30 | Unspecified |  | auto | m1 | Pad |
| p7 | Bushing | mechanical | 18 × 16 × 16 | Unspecified |  | auto | m1 | Bushing |
| p8 | Lead screw | mechanical | 220 × 8 × 8 | Unspecified |  | auto | m2 | Lead screw |
| p9 | Nut | mechanical | 14 × 18 × 18 | Unspecified |  | auto | m2 | Nut |
| p10 | Hand knob | mechanical | 10 × 32 × 32 | Unspecified |  | auto | m2 | Hand knob |
| p11 | Foot | mechanical | 22 × 22 × 12 | Unspecified |  | auto | m1 | Foot |

## Design system

- Label constraints, inferences and unknowns separately.
- Show interference before assembly or motion claims.

**Tone:** Specific, conditional and non-certifying. · **Colors:** _unspecified_ · **Typography:** Plain labels and millimetre dimensions.

## Agent concurrency

Up to 1 builder(s) in parallel.

**Shared files (serialize edits)**

- mechanicalDesign JSON contract

**Rules**

- One builder; two sequential waves.
- Do not edit the locked contract.
- Stop rather than invent passages, fasteners, tolerances or a travel remedy.

## Controls and tests

| Area | Check | Method |
| --- | --- | --- |
| Contract integrity | Compare the later builder input with the supplied JSON. | Exact structural JSON comparison; no dimension edits. |
| Opening | Review pad orientation and nominal gap. | Calculate 142 − (40 + 18) − 2 × 3 = 78 mm, conditional on inward pads. |
| Travel | Review both endpoints against supports and rods. | Compare X82..100 and X202..220 with support X212..228 and rod end X220. |
| Interfaces | Review passages, fits, thread and retention. | Mark each absent definition unresolved; defer CAD geometry review. |
| Future bench checks | Propose visual access and unloaded slow adjustment only after conflicts are resolved. | Planning only; stop at suspected interference; record no physical result. |

## Dependencies

| Dependency | Kind | Reason |
| --- | --- | --- |
| Supplied mechanicalDesign JSON | data | Locked parameter input for a separate deterministic CAD builder. |
| Separate deterministic CAD builder | service | Later source generation and geometric measurements; not executed in this review. |

## Risks

| Risk | Mitigation |
| --- | --- |
| Opening-direction travel intersects the right end support. | Flag the 8 mm envelope overlap; do not call 60 mm usable or change coordinates. |
| Rod and screw crossings lack specified passages and retention. | Keep interfaces unresolved pending separate CAD review and design decisions. |
| Twenty named instances may conceal unspecified attachment hardware. | Treat four bushings as inferred and the count as provisional, not a complete assembly specification. |

## Open questions

- Which jaw faces carry the pads, and how are pads attached?
- How many bushings are intended, where are they seated, and how are they retained?
- What passages, attachments, screw thrust support, nut restraint and knob coupling are intended?
- What thread, fit, friction, allowable load and motion protection would be specified?
- How is the foot-to-base interface located relative to the stated origin?
- How will later CAD review address the opening-end overlap without silently changing this contract?
- What electrical integration, if any, is intended? None is specified or implemented.
- What physical prototype and non-destructive validation would be needed before any performance claim?

## Evidence

- `fixture-question` Hold the sample for inspection
- `fixture-dimensions` Fixed dimensions and interfaces
- `fixture-concept` Three modules, twenty proposed parts

## Recorded investigation basis

**Frozen scope:** my canvas revision 1

No linked decision is inferred; review the retained records before treating this draft as a commitment.

### Selected concept

_No selected named concept was present in the frozen package scope._

### Human decision records

_No selected human concept decision record._

### Exact selected material

- `fixture-question` Hold the sample for inspection (content 1)
- `fixture-dimensions` Fixed dimensions and interfaces (content 1)
- `fixture-concept` Three modules, twenty proposed parts (content 1)

## Frozen specification

**Export state:** Needs review · **Specification revision:** 1

**Specification digest:** `484940da9d063d9e464725c080373a09824f12502de03db3496321491c07c0e7`

No human approval for handoff is recorded for this exact specification revision. Downloading or copying this export does not approve it.

### R1 · revision 1 · Needs review

Preserve the supplied mechanicalDesign as a locked, proposed parameter contract.

**Acceptance**

- Reproduce its schema, coordinate system, parameters and limitations exactly; make no silent dimension changes or added parts. Describe CAD generation and measured geometry validation as separate later operations.

**Decision records**

_No exact human decision record._

**Evidence versions**

- canvas=my, nodeId=fixture-dimensions, contentRevision=1

**Assumptions**

_None._

**Unresolved**

- No compiled CAD or measured geometry is supplied.

### R2 · revision 1 · Needs review

Document conditional opening and the proposed travel conflict.

**Acceptance**

- Jaw inner-face gap is 84 mm; inward-facing 3 mm pads on both faces imply 78 mm. From moving-jaw X142..160, closing by 60 mm gives X82..100; opening by 60 mm gives X202..220. The latter overlaps right-support X212..228 by 8 mm and reaches the rod endpoint X220. Do not infer usable travel, rod engagement or a remedy.

**Decision records**

_No exact human decision record._

**Evidence versions**

- canvas=my, nodeId=fixture-dimensions, contentRevision=1

**Assumptions**

- Pads face inward; positive X opens the moving jaw.

**Unresolved**

- Pad placement, endpoint clearance and rod engagement.

### R3 · revision 1 · Needs review

Keep guidance and screw interfaces explicitly unresolved.

**Acceptance**

- Identify guide axes Y45/135 at Z32 and screw axis Y90 at Z32 crossing stated part envelopes. Nominal Ø10/Ø10.4 and Ø16/Ø16.2 diameters do not validate sliding or retention. Do not assume passages, housing locations, thread engagement, nut anti-rotation, screw thrust support or knob coupling. Jaw minimum Z11 above base top Z10 implies only a nominal 1 mm gap.

**Decision records**

_No exact human decision record._

**Evidence versions**

- canvas=my, nodeId=fixture-dimensions, contentRevision=1

**Assumptions**

- The displayed base clearance refers to the jaw-to-base gap.

**Unresolved**

- Fits, loads, friction, passages, retention and protection against overtravel.

### R4 · revision 1 · Needs review

Reconcile the named-part BOM without treating the count as proof of completeness.

**Acceptance**

- Count base 1, rods 2, supports 2, jaws 2, pads 2, screw 1, nut 1, knob 1 and feet 4: 16 instances. Four bushings would make 20, but their quantity and allocation are inferred, not locked. Do not add fastening hardware or claim that 20 parts establish usefulness, retention or manufacturing readiness.

**Decision records**

_No exact human decision record._

**Evidence versions**

- canvas=my, nodeId=fixture-concept, contentRevision=1

**Assumptions**

- Four bushings are a candidate allocation solely for count reconciliation.

**Unresolved**

- Bushing allocation and all unspecified attachments.

### R5 · revision 1 · Needs review

Sequence review and proposed checks without implying execution.

**Acceptance**

- Review interfaces and travel first; then plan base/feet/supports, guides/jaws/pads, and screw/nut/knob. Defer geometry measurement to separate CAD work. Only after conflicts and interfaces are resolved, propose visual access and unloaded, slow manual adjustment with a stop at suspected interference. Report no fabricated prototype, sample-damage test, repeatability, holding force or successful inspection.

**Decision records**

_No exact human decision record._

**Evidence versions**

- canvas=my, nodeId=fixture-question, contentRevision=1
- canvas=my, nodeId=fixture-concept, contentRevision=1

**Assumptions**

_None._

**Unresolved**

- Prototype validation and any electrical integration are outside this review.

### Exact reference availability

- canvas=my, nodeId=fixture-dimensions, contentRevision=1 — **current**
- canvas=my, nodeId=fixture-concept, contentRevision=1 — **current**
- canvas=my, nodeId=fixture-question, contentRevision=1 — **current**

### Honest unresolved context

**Contradictions, risks and missing evidence**

- Opening-direction travel intersects the right end support. — Flag the 8 mm envelope overlap; do not call 60 mm usable or change coordinates.
- Rod and screw crossings lack specified passages and retention. — Keep interfaces unresolved pending separate CAD review and design decisions.
- Twenty named instances may conceal unspecified attachment hardware. — Treat four bushings as inferred and the count as provisional, not a complete assembly specification.

**Risks accepted for this exact handoff**

_None. This revision has no handoff approval._

**Unanswered questions**

- Which jaw faces carry the pads, and how are pads attached?
- How many bushings are intended, where are they seated, and how are they retained?
- What passages, attachments, screw thrust support, nut restraint and knob coupling are intended?
- What thread, fit, friction, allowable load and motion protection would be specified?
- How is the foot-to-base interface located relative to the stated origin?
- How will later CAD review address the opening-end overlap without silently changing this contract?
- What electrical integration, if any, is intended? None is specified or implemented.
- What physical prototype and non-destructive validation would be needed before any performance claim?
- No compiled CAD or measured geometry is supplied.
- Pad placement, endpoint clearance and rod engagement.
- Fits, loads, friction, passages, retention and protection against overtravel.
- Bushing allocation and all unspecified attachments.
- Prototype validation and any electrical integration are outside this review.

**Assumptions**

- Pads face inward; positive X opens the moving jaw.
- The displayed base clearance refers to the jaw-to-base gap.
- Four bushings are a candidate allocation solely for count reconciliation.

**Requirements without an exact decision record**

- R1
- R2
- R3
- R4
- R5

**Pending claims / requirements awaiting human review**

- R1
- R2
- R3
- R4
- R5

Some retained historical material is unavailable. Its frozen identifiers remain visible, but this export does not restore or disclose the unavailable private content.