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I searched the archives and only found one old thread but wondered if anyone had any luck with re-welding a new band that has cracked at the weld?
I realize Im being a tight wad here but occasionally I get a new blade that on its first round on the mill will come off with a slight crack at the weld. Its rare and my blade supplier always replaces them without question but I keep the old ones. These blades will only have a 3-4 hundred feet on them usually so they are basically new and undamaged. Its not worth the shipping to return them. We do our own resharpening and recently got to wondering about just running a bead down the crack (mig) and grinding it. Either that or I was going to see if I had enough travel in the tension to cut one tooth out but Im not sure Ill have an extra inch or two of travel.
Of course they are free so just tossing them in the scrap pile is fine but with blade prices where they are I got to thinking...
i also have bands that have broken -though not at the weld-that i also would like to find an answer on how to reweld ,silver solder,braze or whatever would work?
Hey Mark, I did a little welding after VoTec in the industry. Never certified Tungsten Inert Gas (TIG) But passed that test in school. For such an intricate weld as on a saw blade, I would think TIG welding would be the way to go. Walk the rod... walk the rod.
Do you get a lot more footage / spin hours on your other blades? Or is it just a few more?
Ken Cook from Cooks' saw wrote a nice article about grinding gullets, and his conclusion is that it does not help at all. I went to school for Engineering and agree that it can't help. Cracks in the gullet are the result fatigue that results in stress cracks. Grinding out material will not help that, and in fact will accelerate it, since there's less material to resist the stress.
Welding on the other hand would seem like it could help, but you'd want to fill the entire crack with material, then grind it flat again, to avoid "thumps" as the band goes around the bandwheels. Basically just like welding up a new blade. This would make sense on a relatively new blade, but not on one that has been through several saw - resharpen cycles, since there will be many fatigue cracks that developed in many of the gullets.
What size bandwheels does your mill have, and have you checked to be sure they are "co-planer"? I had a real problem with band life until I took some time to align my bandwheels and make sure they were both perfectly in line and in the same plane. I wrote up how to do it somewhere here, so just search a bit to find that.
Best of luck.