Neogrid Openscad

NeoGrid OpenSCAD Code Generation

Generates OpenSCAD code for 3D-printed connectors that join store-bought divider materials (MDF, plywood, acrylic) into custom drawer organization layouts.

Required Reading Before Generating Code

CRITICAL: NeoGrid is a HYBRID system:

• 3D-print: Connectors only (~50g filament per piece)
• Buy/cut: Divider material (MDF, plywood, acrylic, uPVC) from hardware store

Official NeoGrid 2.0 implementation:

• QuackWorks GitHub: https://github.com/AndyLevesque/QuackWorks/tree/main/NeoGrid
• Local clone: /Users/aaron/workspace/infra/neat-little-package/.tmp/QuackWorks/NeoGrid/
• Main files: Neogrid.scad (connectors), DrawerLabelsAndHandles.scad (labels)
• License: CC BY-NC-SA 4.0

System references:

• home-organization/neogrid-reference.md - System overview and material selection
• Fetch QuackWorks repo for current parameter syntax

Core Understanding (Critical Architecture)

What Makes NeoGrid Different: Hybrid Economics

NOT a fully 3D-printed system. NeoGrid separates components by manufacturing efficiency:

3D-print the connectors:

• Junctions (X, T, L, I, End pieces)
• ~50g filament per connector
• Print time: 1-3 hours depending on connector type
• Functional geometry (channels, retention, base mounting)

Buy the dividers:

• 8.5mm uPVC utility board (UK standard)
• 6.35mm (1/4") plywood (US standard)
• 3mm-9mm+ MDF, acrylic, foam board
• Cost: ~$10-20 for entire drawer system vs hundreds in filament
• Faster: Cut to length vs 50+ hours printing sheets

Why this works:

• Connectors require precision geometry (print it)
• Dividers are simple rectangles (buy it cheap)
• Material cost: 90% savings vs fully printed
• Assembly time: Cut dividers once, reuse connectors anywhere

Critical Parameter: Material Thickness

Most important parameter in entire system:

Material_Thickness = 8.5;  // MEASURE YOUR ACTUAL MATERIAL!

Why it's critical:

• Even 0.2mm variation affects friction fit
• Tolerance: ±0.15mm for proper grip
• Too loose: Dividers wobble, layout collapses
• Too tight: Dividers won't insert, connectors crack

Process:

1. Buy material from hardware store
2. Measure with calipers (NOT ruler)
3. If painted: Measure AFTER painting (adds thickness)
4. Print ONE test connector
5. Verify fit before batch printing
6. Adjust parameter by 0.1-0.2mm if needed

Common materials and actual measurements:

Base System Integration

Connectors attach to drawer bottom via one of four base types:

Gridfinity (42mm grid):

• Snaps onto Gridfinity baseplate
• Allows repositioning without re-taping
• Grid alignment ensures straight layouts
• Use for drawers with existing Gridfinity setup

OpenGrid (25mm grid):

• Vertical wall mounting option
• Less common for drawer use
• Two variants: Full (6.8mm) or Lite (3.4mm)
• Optional directional snaps for vertical strength

Flat (30mm grid or custom):

• No snap features, just flat base
• Use adhesive/tape to secure
• Flexible grid sizing
• Simple, universal option

None (no base):

• For non-drawer applications
• Dividers rest on surface directly
• Minimal filament usage

Connector Type Navigation

NeoGrid has 6 connector types (plus drawer label holders). Each has dedicated subpage:

Drawer labels (bonus accessory):

• Label holders that mount to drawer fronts
• Hook mount (standard) or adhesive tape
• Not part of divider system, but commonly paired
• Read: ./drawer-labels.md

Material Selection Guide

Choose divider material based on budget, availability, and drawer use:

Detailed material comparison: ./hybrid-approach.md

Quick reference:

Critical reminder: Measure actual material thickness before printing. Nominal ≠ actual.

Base Selection Guide

Choose base system based on drawer setup:

Detailed base options: ./base-options.md

Quick decision framework:

Do you have Gridfinity baseplate in drawer?
├─ Yes → Use Gridfinity base (42mm)
└─ No
   ├─ Want to add Gridfinity later? → Use Gridfinity base (future-proof)
   └─ No Gridfinity needed
      ├─ Want easy repositioning? → Use Flat base + adhesive (30mm)
      └─ Permanent install → Use None (minimal filament)

Multi-tile support (Gridfinity only):

grid_x = 2;  // 2 tiles wide (84mm)
grid_y = 3;  // 3 tiles deep (126mm)

Only X Intersection connectors support multi-tile bases currently.

Connector Selection Framework (Decision Layer)

When User Describes Drawer Layout

Use this decision tree to select connector types:

Ask these questions:

1. How many dividers meet at junction?

   • Four (cross pattern) → X Intersection
   • Three (T pattern) → T Intersection
   • Two (corner) → L Intersection
   • Two (straight line) → I Junction
   • One (end of divider) → Straight End

2. Where is junction located?

   • Interior grid point → X Intersection (most versatile)
   • Edge with perpendicular divider → T Intersection
   • Corner → L Intersection
   • Drawer opening edge → Vertical Trim

3. What's the layout pattern?

   • Regular grid → Mostly X Intersections + edges (T, L, End)
   • Asymmetric compartments → Mix of all types as needed

Example layout analysis:

User: "3×3 grid in my drawer"

Analysis:
- Interior: 4 X Intersections (where grid lines cross)
- Edges: 8 T Intersections (where dividers meet drawer edge)
- Corners: 4 L Intersections (drawer corners)
- Total: 4 X + 8 T + 4 L = 16 connectors + 16 top pieces

Start with X Intersections: Most versatile, works for testing material fit.

Code Generation Best Practices

Parameter Organization

Always declare these parameters at top of file:

// CRITICAL: Material measurement
Material_Thickness = 8.5;      // MEASURE actual material with calipers!
Channel_Depth = 20;            // How deep material sits in connector
Wall_Thickness = 4;            // Connector wall thickness

// Base system selection
Selected_Base = "Gridfinity";  // Gridfinity | openGrid | Flat | None
grid_size = 42;                // Auto-set based on Selected_Base
grid_x = 1;                    // Tiles horizontally (Gridfinity only)
grid_y = 1;                    // Tiles vertically (Gridfinity only)

// Gridfinity-specific
Added_Base_Thickness = 1;      // Extra base height beyond profile

// OpenGrid-specific
openGrid_Full_or_Lite = "Lite";                     // Full | Lite
openGrid_Directional_Snap = false;                   // Vertical mounting
openGrid_Directional_Snap_Orientation = 1;           // 1-4 rotation

// Flat base
Flat_Base_Thickness = 1.4;     // Base thickness in mm

// Material retention
Retention_Spike = false;       // Add spikes for MDF (soft materials)
Spike_Scale = 1;               // Scale spike size

// Part selection
Select_Part = "X Intersection"; // See connector type options
Top_or_Bottom = "Both";        // Top | Bottom | Both

// Top chamfers
Top_Chamfers = true;           // Ease material insertion

Why this order: Critical material parameter first, base system second, optional features last.

Two-Piece System (Base + Top)

All connectors use two-piece design (except Vertical Trim):

// Bottom piece (has base attachment - Gridfinity/openGrid/Flat)
NeoGrid_X_Intersection_Base(
    Material_Thickness,
    Channel_Depth = Channel_Depth,
    Wall_Thickness = Wall_Thickness,
    grid_size = grid_size
);

// Top piece (caps the junction, no base)
NeoGrid_X_Intersection_Top(
    Material_Thickness,
    Channel_Depth = Channel_Depth,
    Wall_Thickness = Wall_Thickness,
    grid_size = grid_size
);

Why two pieces:

• Base provides stability and positioning
• Top locks dividers in place vertically
• Allows swapping divider materials without reprinting bases
• Separate prints = less support material

Assembly: Insert dividers into base channels → Place top piece over junction.

Material Thickness Workflow

When user says "I need connectors for X dividers":

1. Ask about material type and measurement:

   • "What material? (MDF, plywood, acrylic, uPVC)"
   • "Have you measured thickness with calipers?"
   • "If painted, measure after painting"

2. Set Material_Thickness parameter:

   Material_Thickness = 8.5;  // User's measured value
   

3. Recommend test print:

   • "Print ONE X Intersection (base + top) to verify fit"
   • "Divider should friction-fit securely without forcing"
   • "Adjust parameter by ±0.1-0.2mm if needed"

4. Batch printing guidance:

   • "After fit verified, print remaining connectors"
   • "All connectors use same Material_Thickness"
   • "Orientation: Parts print upright as displayed in QuackWorks"

Connector Module Integration

Read the QuackWorks source, don't reinvent:

// DON'T write connector geometry from scratch
// DO fetch current modules from QuackWorks repo

// Option 1: Direct include (if user has BOSL2)
include <BOSL2/std.scad>
include <BOSL2/rounding.scad>
include <path/to/Neogrid.scad>

NeoGrid_X_Intersection_Base(...);

// Option 2: Paste relevant module from QuackWorks
// (if user wants standalone file)
module NeoGrid_X_Intersection_Base(...) {
    // [copied from Neogrid.scad]
}

When to use each connector type: See connector-types/*.md for detailed geometry and use cases.

Common Pitfalls

Pitfall #1: Hardcoding Material Thickness Instead of Measuring

Problem: User says "I have 1/4 inch plywood", code uses Material_Thickness = 6.35, connectors don't fit.

Why it fails: Nominal thickness ≠ actual thickness. 1/4" plywood can be 6.0-6.5mm depending on manufacturer.

Better approach:

// DON'T assume nominal:
Material_Thickness = 6.35;  // "It's 1/4 inch"

// DO ask user to measure:
echo("CRITICAL: Measure actual material with calipers!");
echo("Even 0.2mm variation affects fit.");
Material_Thickness = 6.4;  // User's measured value

Pitfall #2: Skipping Test Print

Problem: User prints 20 connectors, discovers material doesn't fit, wastes filament.

Why it fails: Material variation, printer tolerance, measurement errors compound.

Better approach:

// Workflow guidance:
// 1. Print ONE X Intersection (base + top)
// 2. Test material fit
// 3. Adjust Material_Thickness ±0.1-0.2mm if needed
// 4. THEN batch print remaining connectors

Include in code comments: Remind user to test before batch printing.

Pitfall #3: Wrong Base System for User's Drawer

Problem: User has no Gridfinity baseplate, code generates Gridfinity base, connectors don't sit flat.

Why it fails: Didn't ask about existing drawer setup.

Better approach:

// Ask before generating:
// "Do you have Gridfinity baseplate in this drawer?"
// ├─ Yes → Selected_Base = "Gridfinity"
// └─ No → Selected_Base = "Flat"  // Use adhesive to secure

Pitfall #4: Forgetting Retention Spikes for Soft Materials

Problem: User has MDF dividers, connectors don't grip firmly, layout sags.

Why it fails: MDF is soft, benefits from retention spikes for friction.

Better approach:

// Check material type:
// "What divider material?"
// ├─ MDF → Retention_Spike = true;
// ├─ Plywood → Retention_Spike = false; (optional)
// └─ Acrylic → Retention_Spike = false; (never)

Pitfall #5: Multi-Tile Grid Without Gridfinity Base

Problem: User wants 2×3 connector grid, code sets grid_x=2, grid_y=3 with Selected_Base="Flat", parameters ignored.

Why it fails: Multi-tile support is Gridfinity-only (currently).

Better approach:

// Warn user:
if (grid_x > 1 || grid_y > 1) {
    echo("WARNING: Multi-tile (grid_x/grid_y) only supported with Gridfinity base");
    echo("For Flat/None base, use grid_x=1, grid_y=1");
}

Quality Checklist

Before delivering OpenSCAD code:

Required elements:

• ✓ Material_Thickness parameter clearly documented with measurement reminder
• ✓ Base system selected based on user's drawer setup
• ✓ Appropriate connector type(s) for layout described
• ✓ Top_or_Bottom set correctly (usually "Both")
• ✓ Retention_Spike evaluated based on material type
• ✓ Test print workflow mentioned in comments

Parameter validation:

• ✓ Material_Thickness: User measured actual material (not assumed nominal)
• ✓ Channel_Depth: Default 20mm (adequate for most drawers)
• ✓ Wall_Thickness: Default 4mm (adequate strength)
• ✓ grid_size: Auto-set based on Selected_Base (don't override unless custom)

Base system compliance:

• ✓ Selected_Base matches user's drawer setup
• ✓ If Gridfinity: grid_x/grid_y set for multi-tile (if needed)
• ✓ If openGrid: Full/Lite and directional snap configured
• ✓ If Flat: Flat_Base_Thickness set
• ✓ If None: User understands no base attachment

Code quality:

• ✓ Parameterized (uses Material_Thickness variable, not hardcoded values)
• ✓ Clear variable names
• ✓ Comments explain hybrid system approach
• ✓ Module calls use QuackWorks functions (don't reinvent)
• ✓ BOSL2 library referenced (required dependency)

User communication:

• ✓ Explained hybrid approach (print connectors, buy dividers)
• ✓ Material measurement workflow emphasized
• ✓ Test print recommended before batch
• ✓ Assembly instructions (base → dividers → top)
• ✓ Connector count calculated if layout specified

Assembly Workflow

Standard NeoGrid assembly process:

1. Design layout: Measure drawer, plan divider pattern
2. Measure material: Use calipers on actual divider material
3. Test print: ONE connector type (X Intersection recommended)
4. Verify fit: Material should friction-fit with slight resistance
5. Adjust if needed: ±0.1-0.2mm on Material_Thickness parameter
6. Cut dividers: Standard length 160mm (or 42mm × N - Material_Thickness)
7. Batch print: All connectors for layout
8. Assemble: Place bases → insert dividers → add tops
9. Install: Place in drawer (on baseplate or with adhesive)

Documentation References

NeoGrid Ecosystem:

• NeoGrid 2.0: Hybrid drawer organization system
• Created by Hands on Katie (Katie)
• Licensed CC BY-NC-SA 4.0
• This skill focuses on CODE GENERATION for connectors

Related skills:

• home-organization/neogrid-reference.md - System overview, material selection, use cases
• For system selection guidance, defer to that skill
• This skill is only for "generate OpenSCAD code for NeoGrid connectors"

Official resources:

• https://handsonkatie.com/neogrid-organise-your-big-items-with-this-free-and-open-source-system/
• https://github.com/AndyLevesque/QuackWorks/tree/main/NeoGrid (authoritative code)
• https://makerworld.com/en/models/1501061-neogrid-2-0-drawer-management-system