Enamel Mug

1. Material Selection:
  - Carbon Steel Sheets: High-quality, low-carbon steel sheets are selected for their durability and formability.
  - Enamel Frit: A powdered glass mixture (silica, feldspar, borax) with metal oxides for color and adhesion.
2. Blanking and Cutting:
  - Steel sheets are cut into circular blanks using hydraulic presses or laser cutting machines.
3. Stamping/Pressing:
  - Blanks are pressed into mug shapes using deep-drawing dies.
  - Handle Formation:
    - Integrated handles: Stamped as part of the mug body.
    - Separate handles: Cut, shaped, and welded/riveted to the mug body pre-enameling.
4. Surface Preparation:
  - Degreasing: Remove oils and contaminants via alkaline baths.
  - Pickling: Immersion in acid (e.g., sulfuric or hydrochloric) to eliminate rust and scale.
  - Neutralization: Rinsed to remove acid residues.
5. Base Enamel Application:
  - Wet Process: Mug is dipped or sprayed with a slurry of enamel frit and water.
  - Dry Process: Electrostatic powder coating for even distribution.
6. Firing:
  - Mugs are fired in a kiln at 800–900°C to melt and fuse the enamel into a smooth, glassy layer.
  - Double Firing: Some processes apply a second enamel coat for durability.
7. Decoration:
  - Screen Printing: Designs are applied using heat-resistant pigments through mesh stencils.
  - Decals: Pre-printed designs transferred onto the mug and fired to bond with the enamel.
  - Hand-Painting: Artisan techniques for custom designs (rare in mass production).
8. Final Firing:
  - Decorated mugs are fired again at 700–800°C to set the colors and ensure adhesion.
9. Edge Finishing:
  - The rim is rolled or ground to eliminate sharp edges.
  - Optional silicone or rubber grip added to the handle base.
10. Quality Control:
  - Visual Inspection: Check for bubbles, cracks, or uneven coatings.
  - Adhesion Test: Tap test to detect delamination.
  - Leak Test: Ensure structural integrity (for lidded mugs).
11. Packaging:
  - Mugs are wrapped in protective materials (bubble wrap, cardboard sleeves).
  - Bulk packaging for wholesale or retail display.
Key Considerations:
- Durability: Enamel thickness (~0.1–0.3 mm) balances chip resistance and flexibility.
- Sustainability: Steel is recyclable, though enamel coating complicates the process.
- Safety: Lead-free pigments and proper ventilation during firing.
Variations:
- Campfire Mugs: Thicker enamel for heat resistance.
- Vintage Styles: Distressed finishes achieved through controlled oxidation.