A. Yes, we cast directly from most RP models and do not require a rubber molding step.
Q. What is the shrinkage rate that I should apply to CAD/CAM models?
A. Milled waxes should be treated as any other wax with respect to shrinkage. However, photopolymer models (Invision, Viper, envisionTEC Perfactory) will generally “grow” in the casting process and produce a piece in metal that is larger than the model. This growth rate will vary somewhat from design to design. Below are some basic guidelines to observe for photopolymers:
Setting Hole: From model to metal 5 to 7% smaller diameter will result.
Ring Size: From model to metal 1 to 2% smaller diameter will result.
Q. How do I calculate the estimated metal weight from my RP Pattern?
You can use the volume calculator in your CAD program.
Q. Is burnout a problem when using RP models?
A. Thermoplastics (Solidscape, Sanders) will burn out cleanly in the same manner as wax. Photopolymers are more difficult to burn out and may require special processing including a mold washing step in order to achieve clean burn out.
Q. What is your turnaround time?
A. Our basic process requires 3 business days, with shipment to you on the 4th business day. However, some RP models (specifically those containing photopolymer resin) may require an extra day as we use a stronger investment material to assure quality.