Saw Blade Tip Loss
These tips had been plated to make them wet and braze well. The plating did wet and braze well but the plating did not stick to the tungsten carbide saw tip at all well.
This is entirely the fault of the manufacturer of the carbide saw tips and in no way reflects on the user.
Here are two pictures of representative notches in the steel saw body where the tips failed. Two features are significant here. At the left of either picture you can see where a small bit of carbide did adhere. On the rest of the notch you can see a sort of textured gray layer. This is the underside of the plating applied to the tungsten carbide. The braze alloy stuck to the steel and the plating stuck to the braze alloy and not to the tungsten carbide.
I took a small box knife and scratched one of the notches on the steel saw body. The plating came off readily exposing the gold layer of braze alloy underneath it.
You can see the same thing in the four pictures below. The top two pictures show two notches from the saw blade. You can see the gray layer the plating as well as little gold specks which is the braze alloy. The braze alloy held to the tungsten carbide wherever you see the gold spec. This may be as much is 1% of the total surface area but it appears to be much less.
The Carbide failed in several places. In one instance that I saw the carbide actually snapped instead of having the surface plating peel off. The braze alloy was lifted off the tungsten carbide surface. If these tips had been properly prepared you would’ve seen nothing but ruptured carbide as in the four pictures above. This is a perfect example of manufacturer error that could have been prevented.
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