U-Joint Rebuild Prompts

Note: These prompts are for when you have access to the reference SolidWorks sample models and want to match them exactly. For learning and from-scratch builds, start with the U-Joint Assembly Tutorial instead.

Reference models location:

C:\Users\Public\Documents\SOLIDWORKS\SOLIDWORKS 2026\samples\learn\U-Joint\

Reference Model Analysis

Before using these prompts, inspect the reference assembly to understand the geometry:

• bracket.sldprt — Mounting base
• Yoke_male.sldprt — Primary yoke arm
• Yoke_female.sldprt — Secondary yoke arm
• Spider.sldprt — Cross hub connecting yokes
• Pin.sldprt — Shaft pin (qty 4 in assembly)
• Crank_shaft.sldprt — Drive shaft
• Crank_arm.sldprt — Actuation lever
• Crank_knob.sldprt — Grip handle
• UJoint.SLDASM — Complete assembly

Prompt 1: Bracket (Exact Parity)

Use this prompt if you want to match the reference bracket exactly and keep the same feature-tree shape.

Create Bracket_v1.SLDPRT from scratch to match the reference model exactly.

Use mm units and do not add extra features.

Required feature tree:
1. Sketch1
2. Base-Extrude-Thin
3. Sketch2
4. Cut-Extrude1

Build steps (exact dimensions):
1. On Front Plane, create Sketch1 using these connected line segments:
   - (0.00, 0.00) to (0.00, 82.55)
   - (0.00, 82.55) to (-57.15, 82.55)
   - (-57.15, 82.55) to (-77.216, 27.494)
   - (-77.216, 27.494) to (-44.45, 0.00)

   Add dimensions to ALL lines, ensure all sketches are fully defined before moving on. 
   Ensure the first and last points are NOT connected, it's an open u-bracket design.

2. Create Base-Extrude-Thin:
   - Mid-plane depth: 38.10
   - Thin wall thickness: 6.35
   - Auto-fillet corners ON
   - Corner radius: 3.175

3. Create Sketch2 on the top planar face (offset plane from Top Plane at 88.90 if needed).

4. In Sketch2:
   - Add centerline from (0.00, 0.00) to (-57.15, 0.00)
   - Add circle centered at (-44.45, 0.00) with diameter 12.70

5. Create Cut-Extrude1:
   - Blind cut depth: 10.00

Validation requirements:
- Report final feature tree names in order.
- Export isometric PNG as bracket_isometric.png.
- Compare against reference bracket isometric and report mismatch status.

Save the part as Bracket_v1.SLDPRT.

Verification snapshot from this run:

Prompt 2: All Yoke Parts (Exact Parity)

Create Yoke_male.SLDPRT and Yoke_female.SLDPRT from scratch to match the reference models exactly.

Reference models:
- C:\Users\Public\Documents\SOLIDWORKS\SOLIDWORKS 2026\samples\learn\U-Joint\Yoke_male.sldprt
- C:\Users\Public\Documents\SOLIDWORKS\SOLIDWORKS 2026\samples\learn\U-Joint\Yoke_female.sldprt

Steps:
1. Inspect the reference yoke parts and extract geometry, dimensions, and feature sequence
2. Build Yoke_male.SLDPRT with exact feature tree and dimensions
3. Build Yoke_female.SLDPRT (may be identical or slightly different)
4. Replicate appearance and material properties
5. Validate: Report feature tree for each yoke and confirm they match reference models

Export isometric PNG for each: Yoke_male_isometric.png and Yoke_female_isometric.png

Prompt 3: Spider and Pin

Create Spider.SLDPRT and Pin.SLDPRT from scratch to match the reference models exactly.

Reference models:
- C:\Users\Public\Documents\SOLIDWORKS\SOLIDWORKS 2026\samples\learn\U-Joint\Spider.sldprt
- C:\Users\Public\Documents\SOLIDWORKS\SOLIDWORKS 2026\samples\learn\U-Joint\Pin.sldprt

Steps:
1. Inspect reference parts and extract exact dimensions and feature sequences
2. Build Spider.SLDPRT: cross-shaped hub with four radial bores for pins
3. Build Pin.SLDPRT: cylindrical shaft with head flange
4. Match all critical dimensions and tolerances
5. Validate: Report feature tree for each part

Export isometric PNG for each: Spider_isometric.png and Pin_isometric.png

Prompt 4: Crank Parts (Shaft, Arm, Knob)

Create Crank_shaft.SLDPRT, Crank_arm.SLDPRT, and Crank_knob.SLDPRT from scratch to match reference models exactly.

Reference models:
- C:\Users\Public\Documents\SOLIDWORKS\SOLIDWORKS 2026\samples\learn\U-Joint\Crank_shaft.sldprt
- C:\Users\Public\Documents\SOLIDWORKS\SOLIDWORKS 2026\samples\learn\U-Joint\Crank_arm.sldprt
- C:\Users\Public\Documents\SOLIDWORKS\SOLIDWORKS 2026\samples\learn\U-Joint\Crank_knob.sldprt

Steps:
1. Inspect all three crank parts and extract geometry
2. Build Crank_shaft.SLDPRT with drive flange and mounting holes
3. Build Crank_arm.SLDPRT with connection bore and grip section
4. Build Crank_knob.SLDPRT with sphere body and connection post
5. Match all critical dimensions
6. Validate: Report feature tree for each part

Export isometric PNG: Crank_shaft_isometric.png, Crank_arm_isometric.png, Crank_knob_isometric.png

Prompt 5: Assembly Build (Exact Parity)

Create UJoint.SLDASM from scratch to match the reference assembly exactly.

Reference assembly: C:\Users\Public\Documents\SOLIDWORKS\SOLIDWORKS 2026\samples\learn\U-Joint\UJoint.SLDASM

Steps:
1. Inspect reference assembly: component tree, mate list, DOF constraints
2. Insert all 8 parts (or required qty) with exact mate sequence
3. Replicate every mate (coincident, concentric, distance, angle, etc.)
4. Validate final assembly:
   - All parts present in correct locations
   - All mates fully defined (no under-constraint)
   - No over-constraint
   - No interference between parts
   - Mechanism articulates smoothly (if applicable)
5. Report:
   - Total mate count and types
   - Interference analysis
   - Motion summary (free DOF, constrained DOF)

Export isometric PNG of final assembly.

Prompt 6: Final QA and Parity Check

Perform final parity check between your generated parts/assembly and the reference UJoint.SLDASM.

Checklist:
- [ ] All 8 parts exist and are correctly named
- [ ] Each part feature tree matches reference model
- [ ] Assembly has all required mates
- [ ] Assembly is fully defined
- [ ] No interference detected
- [ ] Crank shaft and driven components articulate correctly
- [ ] All dimensions within ±0.5% of reference models
- [ ] Material properties match (if specified)
- [ ] Appearance/color matches reference (if specified)

For any mismatches:
- Identify which part or mate differs
- Report the specific deviation
- Provide corrective action (re-build part, adjust mate, etc.)
- Re-validate after correction

Generate final pass/fail report with images (isometric view from 3 angles).

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When to Use These Prompts

Use these prompts if:

• You want to match the exact SolidWorks reference sample
• You're validating MCP tool accuracy against known geometry
• You need a precise baseline for comparative testing

Use the U-Joint Assembly Tutorial if:

• You're learning MCP and the Prefab UI workflow
• You want to build from scratch without reference constraints
• You want to modify dimensions for your application
• You're designing a custom U-joint variant

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Related

• U-Joint Assembly Tutorial (From Scratch)
• Prefab UI Dashboard
• Tool Catalog