|Possible Fault Cause||Solution|
|Incorrect Water or Powder Ratio||Ensure Correct Ratio P:W|
Conventional Mix 40:100
Vacuum Mix 38:100
|Incorrect Burnout Cycle||Follow recommended burnout cycle.|
Ensure furnace ramp does NOT exceed 250°C/Hr.
Ensure first stage burnout temperature is kept in the range 220°C - 250°C and is held for 4.5 hours minimum. If problem still occurs increase hold time.
|Excessive Casting Forces||Centrifugal casting: Lower torque and RPM settings.|
Vacuum casting: Reduce over pressure.
|Disturbed Flask during setting||After investing bench set and do NOT move flask, strip base or remove tape for a minimum of 90 minutes.|
|Over working investment||Ensure all flasks are poured and removed from vacuum tank and put on bench to set by max. 9 minutes from starting mixing.|
|Waxes too close||Waxes too close together creating a very thin wall of investment. Waxes too close to side or top of flask; ensure min. 5mm gap to top and sides of flask.|
|Slurry too hot or cold||Adjust slurry temperature to 21°C +/- 1°C by increasing or decreasing water temperature.|
|Moulds dried out before burnout||If flasks are left on bench for more than 4 hours before burnout place a damp towel over the tops of the flasks to stop them drying out. Do NOT leave flasks in furnace overnight before burnout.|
|Flask base leak during investing||Ensure good seal between wax sprue and base. It is suggested that it be sealed with molten wax.|