SIAM CASTING POWDERS LTD.
HIGH QUALITY INVESTMENT POWDERS
AND CASTING EQUIPMENT

 

Content on this page requires a newer version of Adobe Flash Player.

Get Adobe Flash player

Technical data
Siam Casting Powders Ltd
Jewellery Trouble Shooting
Casting problems
Mould Rubber problems
Wax Pattern problems
Mixing Guide
Burn Out
Casting Temperature Guide
Melting point and specific
gravity of jewellery alloys
Comparative Weights
and Measures
 
    TECHNICAL DATA Technical data
Jewellery Trouble Shooting Mould Rubber Problems  
 

Problem Cause Remedy
Cut mould does not seal
Evenly (warping)         
Rubber used in packing has
begun to vulcanise.
Use new rubber.
Mould under packed.    Ensure the work time is fully used.
Normally 8 minutes.
Mould over packed.       Review mould packing procedure. Lay strips
in same direction.
Voids in mould
(air entrapment)
modle not filled in with rubber. Pack rubber pieces into and around modle.
Platen not at curing temperature. Preheat vulcaniser  to 155 C.
Mould not cured for recommended time.

Tighten vulcaniser ½ turn past first resistance.
Repeat every two minutes until platens are in
contact with frame and handle cannot be
turned without resistance. Allow 15 minutes
at 155 C for every 6 mm. for intricate moulds
allow 20 minutes at 145 C for every 6 mm.

Mould  delaminates  after  curing Surface of strips not clean. Use new strips. Do not contaminate surfaces with hands  and protect  from extraneous
dirt or dust.
Rubber is old. Use new rubber.
Mould not cured long enough. Use correct times and temperatures.
Mould soft and sticky in centre Under  heated. Check  temperature of  platens.
Cure cycle too short. Cure  for 15 minutes for every 6 mm.
Mould has pebbly surface.Mould is sticky and scorched.
Excessive shrinkage.
Lack of flexibility.
Overheated. Check  calibration of  vulcaniser.