📉 Sidewall Thinning
Causes, Solutions & Prevention in Thermoforming
Excessive thinning on vertical sidewalls. Reduces structural strength. Critical for load-bearing parts.
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⚠️Root Causes by Category
⚙️ Process
- Sheet too hot — excessive sag
- No pre-stretch before forming
🔲 Mold / Tooling
- Deep draw without plug assist
🧪 Sheet / Material
- Sheet thickness insufficient for depth
📐 Design
- Draw ratio too high (>4:1)
✅Solutions & Corrective Actions
Step 1
- Use plug-assist with heated syntactic foam
Step 2
- Pre-stretch to pre-distribute material
Step 3
- Increase sheet gauge
Step 4
- Reduce forming temperature to minimize sag
🛠️Step-by-Step Troubleshooting
1
Step 1
Use plug-assist with heated syntactic foam
2
Step 2
Pre-stretch to pre-distribute material
3
Step 3
Increase sheet gauge
4
Step 4
Reduce forming temperature to minimize sag
❓Frequently Asked Questions
What causes sidewall thinning?
Sheet too hot — excessive sag; No pre-stretch before forming; Deep draw without plug assist
How to fix sidewall thinning?
Use plug-assist with heated syntactic foam
How to prevent sidewall thinning?
Prevention requires systematic process control: verify sheet temperature, maintain mold vents, ensure proper material drying, and document optimal parameters.
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