Spring Generator

Spring Generator

File: Shape_Generation_Scripts/Spring_Generator.py
Version: 1.0
Document Type: Part

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Description

Generates a parametric helical compression spring solid directly in CATIA from user-defined parameters. The spring geometry is built using a GSD helix as the sweep path and a Part Design Rib as the solid. A circular wire cross-section is swept along the helix to produce a fully solid spring body. Settings are saved between sessions.

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Requirements

Requirement	Value
Python	>= 3.10
pycatia	>= 0.8.3
wxPython	Required
Open document	Part
Hybrid Design Mode	Should be off (script handles this automatically)

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Usage

1. Open a CATPart document
2. Run the script
3. The parameter dialog appears — enter your spring parameters
4. Click OK — a progress bar shows while the geometry is being created
5. The spring solid is added as a new body in the part

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Parameters

Parameter	Description
Wire Diameter (mm)	Diameter of the wire cross-section
Coil Diameter (mm)	Mean coil diameter (centre of wire to centre of wire)
Free Length (mm)	Overall uncompressed length of the spring
Number of Coils	Total number of active coils
Clockwise	Winding direction — ticked = right-hand (clockwise), unticked = left-hand

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Validation

The script validates inputs before generating and exits with an error if:

• Wire diameter is zero or negative
• Coil diameter is zero or negative
• Free length is zero or negative
• Number of coils is zero or negative
• Pitch (free length ÷ coils) is less than or equal to wire diameter (coils would overlap)
• Wire diameter is greater than or equal to the coil radius (physically impossible geometry)

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Settings Persistence

Parameters are saved automatically to:

%APPDATA%\pycatia_scripts\Spring_Generator\user_presets.json

The next time the script runs, your last-used values are pre-filled in the dialog.

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Notes

• The spring axis is aligned with the Z-axis, with the base at the origin
• The body is placed in a new body in the part named Spring
• Hybrid Design Mode is temporarily disabled during generation if it is on, and restored afterwards
• The helix, axis line, profile plane, and sketch are left as construction geometry in the part tree; only the Rib solid is the final output