Carbide is an industrial steel applied to blades, bits and other tools used to cut hardwood. Carbide, also known as tungsten carbide, has a formula consisting of half tungsten and half carbide and is three times stiffer than the steel commonly used on other types of wood-cutting tools. Woodcutting tools tipped with carbide have distinct advantages over standard woodworking tools.
Carbide remains sharper longer than plain steel, which makes makes a carbide cutting tool more efficient. Carbide enables blades to cut faster without binding, which reduces load on woodworking machines. Normal-steel cutting tools dull fast. When blades get dull, they burn the wood, cause chipping, shatter the grain and cause grain blow-out. Sharp, carbide-tipped tools are far more efficient, cutting faster and needing sharpening less often than common steel blades.
Carbide tools make the cleanest, straightest cuts of any of the woodworking tools, and cause little or no grain damage. When cuts are clean and straight, woodworking joints fit better and glue bonds are tighter. A carbide tool’s clean cut reduces the incidence of kickback, a major cause of woodworking accidents.
Some hardwoods contain small particles of silica or minerals that can dull normal steel. Particleboard and other composite wood products may contain sand, small rocks or other kinds of debris in their cores that can damage or even ruin a common steel blade instantly. Carbide tools are tough enough to cut through most debris without causing any damage to the blade or its tip. Bullets, nails and screws are commonly found inside rough, re-purposed lumber. If you hit one of these things with a normal blade, it’s finished. A carbide-tipped tool may cut through them and you won’t even notice.
Carbide tips can be replaced when they wear out or break, and most tool-sharpening shops can weld new tips onto a cutting tool. The initial cost of a carbide-tipped tool is more, but the tips are replaceable, making the tool more affordable in the long run. Carbide-tipped tools last almost indefinitely if the blade body or router-bit shaft remains in good shape. It’s not uncommon for carbide-tipped woodworking tools to last 20 years or more if they are taken care of and the tips are replaced regularly.