Design Choices to Reduce Thermoforming Costs

In thermoforming, draft angles are essential for efficient part release, tooling life, and overall production cost. Poor or insufficient draft leads to sticking, deformation, trimming issues, and increased cycle time.

At HIPLEX Technologies, we engineer optimal draft angles to ensure smooth demolding, consistent part quality, and reduced operational cost.

INCORPORATING PROPER DRAFT ANGLES

WHAT IS A DRAFT ANGLE?

A draft angle is the slight taper applied to vertical walls of a thermoformed part to facilitate easy removal from the mold.
Effective geometry and radii design enhances draft performance and smooth part release.

• Measured in degrees (°)

• Applied to all vertical surfaces

• Critical for deep-draw and complex geometries
  Proper draft reduces sticking and contributes to reducing secondary operations like manual part removal.
  In multi-cavity tooling, consistent draft angles ensure uniform release across all cavities.

WHY DRAFT ANGLES MATTER

1. Easy Part Release

• Reduces friction between mold and part

• Prevents sticking and deformation

2. Reduced Cycle Time

• Faster ejection = faster production

• Minimizes downtime and manual intervention

3. Tool Life Improvement

• Less wear and tear on molds

• Lower maintenance cost

4. Improved Product Quality

• Eliminates stress marks and distortion

• Maintains structural integrity

COMMON DESIGN MISTAKES

Zero Draft (Vertical Walls)

• Causes part sticking

• Leads to rejection and damage

Inconsistent Draft

• Uneven release behavior

• Distorted shapes

Excessive Draft

• Alters product dimensions

• Reduces usable volume

HIPLEX ENGINEERING APPROACH

Optimized Draft Range

• Typically 3° to 7° depending on:

  • Material (PET, PP, etc.)

  • Depth of draw

  • Surface finish

Material-Aware Design

• PET requires controlled draft for clarity + release

• Adjust based on:

  • Heat zones

  • Stretch behavior

Functional Draft Integration
Maintain:

• Stackability

• Aesthetic appeal

• Structural strength

TECHNICAL DESIGN PRINCIPLES

Draft Angle Guidelines:

Application Type Recommended Draft

Shallow trays ----------------------------------- 2° – 3°

Medium depth parts -------------------------- 3° – 5°

Deep draw containers ------------------------- 5° – 7°+

Surface Finish Impact

• Glossy surfaces → need higher draft

• Textured surfaces → require more release angle

Plug Assist Influence

• Helps maintain wall distribution

• Reduces excessive thinning
  Correct draft application support wall thickness optimization by reducing material stretching in critical areas.

BENEFITS OF PROPER DRAFT DESIGN

✔ Faster Production Cycles

Smooth release reduces cycle time

✔ Reduced Tool Maintenance

Lower friction = longer mold life

✔ Higher Product Consistency

Uniform shape and finish

✔ Lower Rejection Rates

No sticking or deformation issues

INDUSTRY APPLICATIONS

• Food packaging trays

• PET cups and containers

• Blister packaging

• Industrial thermoformed components

HIPLEX VALUE PROPOSITION

At HIPLEX, we don’t just design products—we engineer manufacturing efficiency.

With optimized draft angles, we deliver:

• Smooth production flow

• Reduced operational cost

• Premium product quality

CONCLUSION

Draft angles are not optional—they are fundamental to efficient thermoforming.

• A well-designed draft:

  • Enhances performance

  • Reduces cost

  • Improves scalability

Explore Complete Design Guidelines

Explore our complete Thermoforming Design Guidelines to understand how geometry, tooling, and process optimization work together to deliver consistent, high-quality production.