Silver soldering band saw blades

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So I bought some silver solder and flux and set out to make my own band saw blades. It really worked well, till I went and turned on the band saw today. The blade I made yesterday had snapped. When I made it, I cut a heck of alot of steel and left it in-tact. I was very surprised when it was snapped today. It snapped about an eighth inch from the solder. I ground it back and re-soldered, made some cuts and as I was walking out of the shop I heard it snap again. I was under the impression that soldering the blade doesn't require annealing but it seems as if I do since the are next to the solder is snapping. Does this sound correct? I have only been heating the blade till the solder melts but the blade does get to a dull red. Am I missing something? Thanks for any advise.
Reply:i have never heard of soldering a blade usually they are spot welded
Reply:Never tryed to solder , have welded together a lot of band saw blades for wood together. Was pretty easy. Never had any problems. used wire feed and then sanded weld smooth with sanding pad.
Reply:I can't imagine a blade being soldered, maybe brazed.  50N silver brazing alloy is commonly used to affix carbide inserts to cutting tools.  But, with almost any brazing process on steel, if the material is glowing red it is probably too hot.  There are some tricks to reading the temperature of steel.  Take a bright shiny piece of steel and heat it with a torch.  Watch it turn straw gold in color, then blue, then a purplish color, then it will turn silver again like it was before it is heated.  This transision occurs right around 1200 degree F which is just below the temp for most brazing processes.  Now, when you go to add filler, you have to heat  and melt the filler with the torch.  Don't use the heat in the part to melt it like you would solder or you will end up overheating the part.  You've got the right temperature if you can maintain a very slightly butter mixture of solid and liquid braze material while still maintaining a proper wetting out.
Reply:Originally Posted by gimpyrobbSo I bought some silver solder and flux and set out to make my own band saw blades . . . I have only been heating the blade till the solder melts but the blade does get to a dull red. Am I missing something? Thanks for any advise.
Reply:I have done tons of silver soldering of all sorts of things, including band saw bands, and frequently use a small propane torch for the work if the part isn't too large for the limited heat output.Due to the lower flame temperature and smaller flame, it's harder to overheat small parts like the blades using propane and easier to allow them to cool down slowly by manipulating and reducing the flame size.