Preci Roto InstructionsPREAT Corporation
- Versatile system for accurate and simple spruing, investing, and casting with plastic or metal rings
- Produces consistent, accurate, and predictable castings
- Facilitates controlled thermal expansion
- Eliminates suck-back and contraction tearing
- Produces very dense and homogeneous precision fit castings
Roto Casting Wheels
Wax casting wheels (with release canal) may be easily placed onto the crucible former. Observe a safe distance between the casting units and the ring former wall. Never place the objects in the thermal center of the ring former.
50 wax pieces (29mm Ø), Large
If the investment material is cold, the plastic investment ring can be removed by placing a flat round disk on the top of the invested cylinder and pushing it out.
A two-stage burn-out is highly recommended. Place the investment mold into a cold furnace and go to 800F and hold for 30-40 minutes. Then proceed to normal burnout temperature and soak. This will prevent investment fracture.
Reserve 8 grams (0.3 oz) of metal for the small cylinders and 12 grams (0.4 oz) for the large ones.
Note: When using metal rings and liners, you should proceed according to the instructions provided by the investment manufacturer.