布拉沃! 特殊钻头: 沉头钻头
Using a countersink drill bit effectively prevents tearing, reduces the possibility of wood splitting, and allows screws to make better contact with the wood. 此外, it makes DIY projects look more professional. Countersink bits have two purposes: 第一的, they drill a pilot hole in the workpiece. A pilot hole is a small hole in …