Stump Grinder Teeth, Thumb Nail Shaped Pretinned from Carbide Processors. We only carry pretinned (with braze alloy/silver solder) thumb nail shaped stump grinder teeth. Each one measures 0.633 long by 0.185 thick and 0.531 wide. We have a special grade of carbide for stump grinder teeth that combines both hardness and toughness. If the stump grinder tip is too tough then it wears out too fast. Our tips last much longer and are the most cost effective.