Atlas of Wax Pattern Defects
Positive
Sharp, thin fin of wax along soluble or core surface.
Varies
Always at parting lines or interface of cavity and features created by slides.
Visual inspection
Wax, under the forces of injection pressure, enters thin gaps around core or soluble print.
| Area | Possible Cause | Potential Correction |
|---|---|---|
| Equipment | Out of calibration |
See Best Practices Section |
| Equipment | High injection pressure |
Decrease injection pressure. Injection pressure can open die by overcoming the available clamping pressure. |
| Equipment | Low clamp pressure |
Increase clamp pressure. |
| Equipment | High wax temperature |
Decrease wax temperature |
| Equipment | Unequal clamping of die |
Clamp die evenly. Balancing blocks may be required. Die may flash if it extends beyond platen |
| Equipment | High injection flow rate |
Reduce injection flow rate. |
| Equipment | Excessive acceleration rate (Machines equipped with electronic injection control). |
Reduce acceleration rate. If available, recommend using volume-based flow vs. time-based flow. |
| Pattern Die | Die wear or damage |
Correct as required. Note: Inspect for worn inserts or damage due to excessive pressure on die closure. Inspect for worn edges at parting line. Inspect for damage on closing die (e.g. raised impact seams). |
| Pattern Die | Undersize soluble wax |
Examine for correct size/adjust print area |
| Pattern Die | Die not completely closed |
Remove wax chips or other interference between die faces |