Argen's Argelite 61 (Noble alloy) with ex3, used it for more years than I can count.....Will cost you about $9.00- $11.00 per unit or less, unless you wax extremely thick like Rob...hehe.
You can use just about any non-precious alloy with the noritake. i agree with the others that getting away from the rex 3 wouldn't be a bad idea (if you still use it, like mentioned, wear a good mask and use a good suction unit). they also sell rex 4, the same composition as the rex 3 without the beryllium. zahn sells both of these.
Argen's Argelite 61 (Noble alloy) with ex3, used it for more years than I can count.....Will cost you about $9.00- $11.00 per unit or less, unless you wax extremely thick like Rob...hehe.
I use REX CC which is beryllium free. It works just fine with my Noritake ex-3. When using NP metal put down a layer of the opaque labeled BA, it helps to prevent any greening coming through the porcelain.