Usually I try to cast in one piece but need a refresh on pre-soldering. I recall fits that were not perfect. Using alloy Superior from Jensen....PWS solder and Laservest soldering investment.
Torch, electric, or laser?Usually I try to cast in one piece but need a refresh on pre-soldering. I recall fits that were not perfect. Using alloy Superior from Jensen....PWS solder and Laservest soldering investment.
Maybe some labs do it differently? But it's how I've been doing it for umpteen years. For me, porcelain to metal noble and high noble metal pre-solder, no flux. For gold crowns and NP, yesInteresting. That's how I was taught. Maybe I should read a bit more?
Maybe that's why it's always worked for me, as I always keep the torch on the solder area (no oxidation) right out of the oven with the solder flowing into the joint, introducing the solder from the other side of the flame, drawing the solder into the heat. Sometime I do have to put the torch to the other side, but with the big tip, it's all in the flame, heat zone as I use a multi orifice tip, it keeps a larger area in the flame, heat zone, than just a little solder tip, in which I would have problems with.Just a quick primer on the basics. Flux helps control the formation of oxide on parent alloy. Solder will not flow over oxidized alloy. Parent alloy must be above melting point of solder to accept the solder. If you use the flame to melt solder it will form a ball and rest on the surface. Leave as much parent alloy exposed as possible to allow even heating in the area and to prevent point heat melting. Cover all margins and thin areas of parent alloy to prevent melting of thin portions.