Atlas of Wax Pattern Defects
Positive
Sharp, thin, linear fin of wax perpendicular to the surface.
Varies
Always at parting lines or interface of cavity and features created by slides, or core prints on soluble or ceramic cores or soluble interfaces.
Visual inspections
Wax, under the forces of injection pressure, unintentionally enters thin areas.
| Area | Possible Cause | Potential Correction |
|---|---|---|
| Equipment | Out of calibration |
See Best Practices Section |
| Equipment | High injection pressure |
Decrease injection pressure. Injection pressure can open the 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 the platen plates. |
| Equipment | High injection flow rate |
Reduce injection flow rate |
| Equipment | Excessive acceleration rate (Machines equipped with electronic injection control) |
Reduce acceleration rate. |
| Pattern Die | Die wear or damage |
Correct as required. Inspect for worn inserts or damage due to excessive pressure on die closure. Inspect for worn edges at parting line. Inspect for damage. (e.g. raised impact seams. Review Best Practices to unsure proper techniques. |
| Pattern Die | Die not completely closed |
Remove wax chips or other interference between die faces. |