⚫ Part Retention Features

Plungers, Grippers, and Contact Point Systems
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Overview

Part retention features ensure the workpiece stays securely positioned during welding, machining, or handling. Three key mechanisms:

Feature Type Use Case Status
Spring Ball Plungers Active Flexible contact, easy load/unload IN PROGRESS
Grippers Passive Fixed protrusions for location PARTIAL
Clamp Shelves Custom Gusset-supported platforms for clamps PLANNED

⚫ Plunger Mounting Assembly (New Design)

🆕 Locator Plate System

A robust plunger mounting system using top and bottom locator plates instead of threading directly into the blade. This provides better strength, serviceability, and alignment.

Assembly Overview

Four-view assembly showing the plunger mounting system:

Plunger Mounting Assembly - Four Views

Top-Left: Front view | Top-Right: Isometric view
Bottom-Left: Side view | Bottom-Right: End view

Component Stack (Top to Bottom)

ComponentColorFunction
Plunger Ball Red (top) Spring-loaded ball contacts the workpiece
Top Locator Plate Green Sits in machined recess; prevents vertical movement
Blade Gray Has pocket machined through for assembly
Bottom Locator Plate Orange Stabilizes nut; slightly different shape than top
Nut (captured) Threads onto plunger body; held by bottom plate
Plunger Body Dark Red Threaded cylinder with internal spring

Cross-Section Diagram

PLUNGER MOUNTING ASSEMBLY - CROSS SECTION ═══════════════════════════════════════════ ┌───┐ │ ● │ ◀── Plunger ball (contacts part) └─┬─┘ │ ┌─────────────┼─────────────┐ │ ░░░░░░░░░░░│░░░░░░░░░░░ │ ◀── GREEN: Top Locator Plate │ ░░░░░░░░░░░│░░░░░░░░░░░ │ (sits in blade recess) └─────────────┼─────────────┘ ══════════════════╪══════════════════ ◀── BLADE (gray) ║ ║ ║ with pocket cut through ║ ┌───────────┼───────────┐ ║ ║ │ ▓▓▓▓▓▓▓▓▓│▓▓▓▓▓▓▓▓▓ │ ║ ◀── ORANGE: Bottom Locator ║ │ ▓▓▓▓▓▓▓▓▓│▓▓▓▓▓▓▓▓▓ │ ║ (stabilizes nut) ║ └───────────┼───────────┘ ║ ║ │ ║ ╚═════════════════╪═════════════════╝ │ ┌───┴───┐ │ NUT │ ◀── Captured nut └───┬───┘ │ │ ◀── Plunger threaded body │ ▼ (extends below blade)

Key Design Features

FeatureBenefit
Recessed Top Plate Green plate sits in a shallow step machined into blade top surface - prevents upward movement under load
Captured Nut Nut is held in pocket by orange plate - cannot spin or fall out during adjustment
No Threading into Blade Plunger held mechanically by plates, not by threads in potentially thin blade material
Fully Serviceable Remove top plate → unthread plunger → replace → reassemble
Perpendicular Alignment Locator plates ensure plunger is exactly perpendicular to blade surface

Assembly Sequence

  1. Machine blade pocket - Cut rectangular pocket through blade with top recess
  2. Insert bottom plate - Orange locator plate goes in from bottom
  3. Insert nut - Drop nut into pocket, resting on bottom plate
  4. Thread plunger - Insert plunger from top, thread into nut
  5. Install top plate - Green plate drops into recess, capturing assembly
  6. Secure - Optional: spot weld or adhesive on top plate edges

Dimensional Parameters

ParameterM5M6M8Description
pocketWidth14mm16mm20mmPocket width in blade
pocketLength14mm16mm20mmPocket length in blade
recessDepth2mm2mm3mmTop plate recess depth
topPlateThickness2mm2mm3mmGreen plate thickness
bottomPlateThickness2mm2mm3mmOrange plate thickness
nutHeight4mm5mm6.5mmStandard nut height
plungerDiameter5mm6mm8mmPlunger body OD

⚠️ Blade Thickness Requirement

Minimum blade thickness = recessDepth + topPlateThickness + bottomPlateThickness + nutHeight + clearance

For M6: 2 + 2 + 2 + 5 + 1 = 12mm minimum blade thickness

For thinner blades, use the T-slot mounting system instead (see below).

  • ✓ Design concept finalized
  • ○ Pocket profile generation macro
  • ○ Top/bottom plate DXF generation
  • ○ JSON schema integration
  • ○ Automatic placement algorithm

📦 Deliverables

fxPlungerPocket.ovm - Pocket and recess generation

fxLocatorPlates.ovm - Plate profile generation

plunger_top_plate_M6.dxf - Laser cut files

plunger_bottom_plate_M6.dxf - Laser cut files

⚫ Plunger Clip System (Alternate Design)

🆕 Snap-Fit Clip Retention

An alternate mounting approach using U-shaped snap clips that wrap around the plunger body. Provides quick assembly and disassembly with positive retention.

Assembly Overview

Isometric view showing the clip-based plunger mounting system:

Plunger Clip System - Isometric View

Isometric view: Clip system with U-shaped retainers wrapping around plunger body

Component Stack (Top to Bottom)

ComponentColorFunction
Plunger Ball Silver Spring-loaded ball contacts the workpiece
Plunger Body Orange Threaded cylinder with internal spring mechanism
Retention Clips Dark Red U-shaped clips wrap around plunger; legs pass through blade slots
Blade Gray (transparent) Has slots cut for clip legs to pass through
Bottom Locator Green Positions plunger body in pocket below blade

Cross-Section Diagram

PLUNGER CLIP SYSTEM - CROSS SECTION ═══════════════════════════════════════════ ┌───┐ │ ● │ ◀── Ball (silver) └─┬─┘ │ ╔══╧══╗ ║ ║ ◀── Plunger body (orange) ║ ║ ┌──────────╫─────╫──────────┐ │ ████ ║ ║ ████ │ ◀── DARK RED: Clips │ █ █ ║ ║ █ █ │ (U-shape wraps body) │ █ █ ║ ║ █ █ │ └──█──█────╫─────╫────█──█──┘ █ █ ║ ║ █ █ ═══════╩══╩════╬═════╬════╩══╩═══════ ◀── BLADE (gray) │ │ ║ ║ │ │ with slots for clip legs └──┘ ║ ║ └──┘ ║ ║ ┌────╬─────╬────┐ │ ░░░░░░░░░░░ │ ◀── GREEN: Bottom Locator └──────────────┘ ║ ║ ╚═════╝ ◀── Plunger extends below

Key Design Features

FeatureBenefit
U-Shaped Clips Wrap around plunger body; snap into position
Slot-Through Legs Clip legs pass through slots in blade; provide positive lock
Tool-Free Assembly Clips can be installed/removed by hand or with simple pry
Spring Action Clip material provides spring force to grip plunger
Bottom Locator Green plate positions plunger body at correct height

Assembly Sequence

  1. Cut blade slots - Laser/waterjet slots for clip legs
  2. Install bottom locator - Green plate goes in pocket below blade
  3. Insert plunger - Drop plunger body through from top
  4. Snap clips - Press U-clips over plunger body; legs go through slots
  5. Verify engagement - Clips should sit flush with blade surface

Dimensional Parameters

ParameterM5M6M8Description
clipWidth12mm14mm18mmOverall clip width
clipLegWidth3mm3mm4mmWidth of each leg
clipThickness1.5mm2mm2.5mmMaterial thickness
slotWidth3.5mm3.5mm4.5mmBlade slot width
slotLength8mm10mm12mmBlade slot length
locatorDiameter10mm12mm16mmBottom locator OD
  • ✓ Design concept finalized
  • ○ Clip profile DXF generation
  • ○ Blade slot generation macro
  • ○ Bottom locator profile
  • ○ JSON schema integration

📦 Deliverables

fxPlungerClip.ovm - Clip profile generation

fxPlungerSlots.ovm - Blade slot generation

plunger_clip_M6.dxf - Laser cut clip file

🔄 Mounting System Comparison

Which System to Use?

CriteriaLocator PlateClip SystemT-Slot
Min Blade Thickness 12mm 6mm 3mm
Assembly Speed Medium Fast (snap-fit) Medium
Load Capacity High Medium Medium
Serviceability Good Excellent Good
Parts Count 4 (plates, nut, plunger) 3 (clips, locator, plunger) 2 (clip, plunger)
Best For Heavy loads, thick blades Quick-change, medium loads Thin blades, edge mounting

💡 Selection Guide

  • Thick blade (≥12mm) + heavy part → Locator Plate system
  • Medium blade (6-12mm) + frequent changes → Clip System
  • Thin blade (≤6mm) or edge-mounted → T-Slot system

⚫ T-Slot Mount (Thin Blades)

For blades too thin for the locator plate system, use the T-slot mounting approach:

🔧 T-Slot Mounting System

Captive nut system for thin blades - quick plunger installation without welding or threading.

T-SLOT CROSS-SECTION (Front View) Plunger ball ○ │ ┌────────┼────────┐ │ ○ │ ○ │ ◀── Clip holes (~2mm offset) │ ┌────┴────┐ │ │ │ NUT │ │ ◀── Nut slides in from side │ └─────────┘ │ │ ┬ │ │ │ │ ◀── T-slot vertical stem └────────┴────────┘ BLADE EDGE RETENTION CLIP (Sheet metal): ┌─────────────────────────┐ │ ○ ○ │ ◀── Tabs snap into holes │ \ / │ │ \_________________/ │ ◀── Spring profile hugs nut └─────────────────────────┘

📏 T-Slot Dimensions

ThreadNut WidthT-StemT-PocketHole Offset
M58mm8.5mm12mm2mm
M610mm10.5mm15mm2mm
M813mm13.5mm18mm2.5mm

🔘 Grippers

Small passive protrusions for part location. Integral to blade profile - cut as part of the blade geometry.

Current Implementation

ParameterDefaultDescription
interval50mmSpacing along edge
radius2mmProtrusion radius
height1mmHeight into pocket

Gripper Profile

GRIPPER DETAIL (Top View) Part sits here ↓ ═══════════╦═══════════════╦═══════════ ║ ║ BLADE ┌──╨──┐ ┌──╨──┐ BLADE │ ● │ │ ● │ │ │ gripper │ │ └─────┘ └─────┘ ↑ ↑ radius=2mm height=1mm

Placement Zones

ZoneDescription
"bottom"Gravity-facing edges only
"sides"Lateral edges only
"both"All edges (default)
"specific"Specified edge IDs
  • ✓ Interval-based placement
  • ✓ Configurable radius/height
  • ○ Placement zone selection
  • ○ Variable shapes (bump, V-notch, etc.)

🔷 Clamp Shelves

Clamp shelves are platforms that extend perpendicular to blade edges, supported by gussets. They provide mounting surfaces for toggle clamps, sensors, or other fixtures.

Shelf Geometry

CLAMP SHELF WITH GUSSETS (Side View) CLAMP ▼ ┌─────────────────────────┐ ◀── Shelf surface │ │ │ ╱ ╲ │ │ ╱ ╲ │ │ ╱ GUSSETS ╲ │ │ ╱ ╲ │ ├─┴─────────────────────┴─┤ │ │ │ BLADE EDGE │ │ │
  • ○ Shelf profile generation
  • ○ Gusset angle calculation
  • ○ Auto-populate mode

📐 Edge Identification System

Hybrid Approach

Three complementary methods for specifying edge locations:

EDGE IDENTIFICATION 1. SEMANTIC: "left", "right", "top", "bottom" 2. NUMERIC (clockwise from bottom-left): ┌─────────────────┐ │ ←4───────3← │ │ ↓ ↑ │ │ 5 2 │ │ →1───────→ │ └─────────────────┘ 3. COORDINATE: {"nearPoint": {"x": 150, "y": 200}}

Related Topics

🔗 Blade Retention

Blade-to-blade interlocking mechanisms

📡 JSON API

Complete plunger configuration schema

🗂️ Zone Management

Apply retention features per zone

🔧 Edge Features

Face detection for feature placement