Dispensing
This is the comprehensive "Epoxy & Enameling Workshop Masterplan".
For Badges, Zipper Pulls, and Metal Tags, the "Dripping" process (Domed Label / Epoxy Potting) creates that luxury 3D crystal effect.
The Challenge: Dust, Bubbles, and Yellowing over time.
The Solution: Proper material selection (PU vs. Epoxy) and strict environmental control.
Here is the plan using the [QLQ System] for High-End European Standards.
💧 Professional Epoxy Dispensing & Enameling Workshop (QLQ System)
Target Products: Metal Badges, Soft Zipper Pulls, Logo Tags.
Goal: Crystal Clear Transparency, Zero Bubbles, No Yellowing (5 Years).
Environment: Class 10,000 Clean Room (Mandatory). Humidity < 50%.
Part I: Material Selection Guide (The Chemistry)
You cannot use one glue for everything. Zipper pulls bend; Badges do not.
1. For Zipper Pulls (Soft PU Resin)
Requirement: Must be flexible. If you use Hard Epoxy, it will crack when the user pulls the zipper.
Formula:
[QLQ Product] Soft Crystal PU Resin (A): 100g.
[QLQ Product] PU Hardener (B): 100g (Usually 1:1 Ratio).
Characteristics: Self-healing surface, UV Resistant (No Yellowing), Flexible.
2. For Metal Badges / Nameplates (Hard Epoxy)
Requirement: Rigid protection, high dome profile.
Formula:
[QLQ Product] Hard Epoxy Resin (A): 300g.
[QLQ Product] Epoxy Hardener (B): 100g (Usually 3:1 Ratio).
Characteristics: Very hard (D Shore 80), High Gloss, cheaper than PU.
Warning: Standard Epoxy yellows in sunlight after 6-12 months. Use [QLQ] UV-Resistant Grade for outdoor badges.
3. For "Cold Enamel" (Colored Infill)
Requirement: Colored liquid to fill recessed logos (replacing traditional hard enamel).
Formula: Clear Epoxy + [QLQ] Color Pastes.
Part II: Equipment Configuration
| Equipment Name | Function | Specification |
| Vacuum Degassing Machine | Removing Bubbles | Rotary Vane Pump. Vacuum > -0.098 Mpa. |
| Auto-Dispensing Robot | Dispensing | 3-Axis (XYZ) Robot. Precision: ±2%. |
| Vacuum Oven | Curing | Temp up to 100°C. Must be level! |
| Flame Polishing Torch | Surface Finishing | Propane/Hydrogen flame to pop surface bubbles. |
| Dehumidifier | Environment Control | Industrial Grade. Must maintain RH < 50%. |
Part III: The Process Workflow (SOP)
Step 1: Pre-Treatment (Clean Base)
Issue: If the metal badge has oil (fingerprints) or mold release agent, the epoxy will separate from the edge ("Fish Eyes").
Action: Ultrasonic Degreasing $\rightarrow$ Bake Dry.
Test: Surface energy > 38 dyne/cm.
Step 2: Mixing & Degassing (The Bubble Killer)
Weighing: Use a digital scale. (Volume ratio is inaccurate due to density differences).
Mixing: Stir slowly in one direction to avoid whipping air into the mix.
Vacuum: Place the mixing cup in the Vacuum Chamber.
Action: Pull vacuum for 3-5 mins until the foam rises and collapses. This removes microscopic air bubbles.
Step 3: Dispensing (The "Dome" Technique)
Method: Needle placement.
Technique:
Start in the center of the logo.
Dispense 80% of the volume.
Allow the resin to flow to the edges naturally (Surface Tension).
Dispense the final 20% to build the "High Dome" (Meniscus).
Note: For sharp corners (Square badges), use a fine needle to guide the resin to the corner without overflowing.
Step 4: Flame Polishing (Debubbling)
Action: Within 5-10 mins of dispensing, pass a Blue Flame quickly over the surface.
Physics: Heat lowers surface tension instantly, causing trapped surface bubbles to pop.
Warning: Do not linger! Burning the epoxy creates smoke/soot.
Step 5: Curing (The Ramp)
Leveling: Parts must sit on a Perfectly Level Table for 30 mins to flatten out.
Baking:
Soft PU: 60°C for 2 Hours $\rightarrow$ 80°C for 2 Hours.
Hard Epoxy: 40°C for 1 Hour $\rightarrow$ 80°C for 3 Hours.
Why Ramp? Heating too fast causes "Boiling" (Bubbles).
Part IV: Troubleshooting (Master's Fixes)
| Problem | Symptom | Root Cause | The Master's Solution |
| Sticky Surface | Resin remains tacky after oven. | 1. Wrong Mix Ratio. 2. High Humidity (>60%). | 1. Use a Scale, not a cup. 2. Turn on Dehumidifier immediately. Moisture kills the Hardener. |
| "Fish Eyes" | Resin pulls away from the edge or logo. | Oil contamination on the metal. | Clean metal with [QLQ] Solvent Cleaner before dispensing. |
| Cloudiness / Haze | Epoxy looks milky white. | Moisture absorption or Cold Resin. | 1. Pre-heat Part A and Part B to 40°C before mixing. 2. Fix Room Humidity. |
| Yellowing | Clear turns urine-yellow. | UV damage or Oxidation. | Switch to [QLQ] Aliphatic PU Resin (10-Year UV Stability). |
| Overflow | Glue runs over the edge. | 1. Too much glue. 2. Edge radius too rounded. | 1. Reduce volume by 5%. 2. Check metal stamping; edges must be sharp to hold the liquid. |
Part V: Daily Routine for the Technician
08:00 | The Environment Check
Check Dehumidifier. Is Room Humidity < 50%? If not, STOP. Do not open glue containers.
Turn on Air Cleaner (HEPA Filter) to remove dust.
09:00 | Machine Calibration
Purge the mixing nozzle of the Auto-Dispenser.
Calibrate the "Shot Size" (Weight per dispensing cycle).
Every 2 Hours | Viscosity Monitoring
Mixed Epoxy thickens over time (Pot Life).
Rule: Mix small batches (e.g., 200g). Use within 30 mins. Discard old mix.
End of Shift | Cleaning
Flush the machine lines with [Purchase Locally] Methylene Chloride or Acetone.
Vacuum Pump: Check oil level. Water/Solvent in the oil ruins the vacuum pressure.
🌟 Featured Album: The "Crystal Dome" Series
Description for the Blog/Guide Album:
💎 The "Crystal Dome" Album: The Art of Perfect Epoxy Potting
Creating a glass-like dome on a metal badge elevates it from "Cheap" to "Luxury." But one bubble ruins the illusion. This series teaches you the clean-room discipline required for perfection.
What you will master:
☁️ The "Humidity" War: Why rainy days are the enemy of Epoxy, and how to use [QLQ Moisture Blockers] to keep production running.
🔥 Flame Polishing 101: A video guide on the exact speed and height to pass the torch to pop bubbles without burning the resin.
🧪 Soft vs. Hard: The definitive guide to choosing between [QLQ PU] for flexible zippers and [QLQ Epoxy] for rigid badges.
📏 The "Meniscus" Secret: How to calculate the exact gram weight needed to create a high dome that stops exactly at the edge without overflowing.
👉 Create flawless, bubble-free badges every time. Unlock the Crystal Dome Album now!
