Mold TexturingTrevor Thorwart

Andrew Meier

Josh Hoover

Introduction

• Mold Texturing– Flexibility– Pleasing Look– Aesthetic feel

Types of Mold Texturing

• Mechanical– Computer Numerical Control (CNC)

– Abrasive Blasting

• Electrical– Electrical Discharge Machining (EDM)

• Chemical Engraving

CNC Engraved

• Areas of use– Logos and Patterns

CNC Engraved

• Basic Milling Operation• Work-piece clamped

down• Tool path computer

generated • Drill follows and cuts

path

Abrasive Blasting Method

• Abrasive particles etch tool– Commonly sand

– High Velocity

• Matte, decorative, and textured finish

Abrasive Blasting

• Advantages– Cheap

– Quick

• Disadvantages– Good for matte surface textures

– Inconsistent surface finish

Abrasive Blasting

Electrical Discharge Machining (EDM)

• Created using electrodes– Shaped tool or wire graphite

• Plasma Etched in CNC pattern

EDM Procedure

• Placed in dielectric fluid• Discharge created• Plasma erodes surface

– Follows CNC path

• Dielectric fluid washes debris away

EDM

• Advantages– Complex and simple surfaces

– Dimensional Accuracy (+/- .0005 in)

– High Range of Materials• Soft and Hard Mold Steels

– Can be fully automated

EDM

• Disadvantages– Low production volume

• Slow cutting

– EDM scale• Must be post-polished

– Blind holes• Difficult Debris Removal

EDM

Chemical Engraving

• Patterning Process using a acid bath

Chemical Engraving Procedure

• Stencil• Mold Masked• Acid Bath• Tooling Dissolves

Chemically Textured Surface

Details Masked

Chemical Engraving

• Advantages– Dimensional– Cost– Tooling

• Disadvantages– Surface Types– Secondary cleaning

operation– Masking

Mold Texturing Areas of Use

• Injection Molding

• Blow Molding

• Compression Molding

• Thermoforming

• Rotational Molding

Other Issues

• Guidelines– Mold Preparation

• Costs– Surface– Tooling– Mold material

• Mold Repair

Conclusion