Good morning everyone!! I was going through some posts and noticed this thread. For any technical support with Argen / Captek products, please never hesitate to contact me or my fellow techincal team. we are very happy to assist you!!
regarding the Noblecrown NF, one must follow the procedures in the letter we ship out with the product. Short cuts cannot be taken or there will be problems. As some of you have noticed, the Noblecrown NF alloy does not pool as most all noble alloys do, so special considerations must be taken. degas from 650-1010°C (1200-1850°F),hold 0 min, (vacuum); Remove oxide with non-recycled 50 micron aluminum oxide. Do not exceed a blast pressure of 4bars or 60 psi. Clean in distilled water in an ultrasonic cleaner for 10 minutes. we recommend running the first coat / wash opaque application 10°c higher than normal to get a better integration with the oxide then followed with regular opaque coats. The oxide color will be different when finishing with a stone vs. a carbide bur. For best results, grind the metal surfaces for porcelain application with cross-cut carbide bur in one direction. When casting if you take the torch off the alloy when melting it an oxide will form. It’s good to purge at least once a month just to make sure porcelain ovens are clean, we recommend using purge-all and purge-all + since those two seem to work best.
Again, we are very happy to assist you in any way possible. You can reach me directly or you can contact Argen technical support directly at 1-800-255-5095