Tungsten carbide is a very hard but brittle material used for cutting tips in metalworking. It is now used in woodturning too. I first made some tungsten carbide woodturning tools many years ago. They had a use, but I had to use them fairly forcefully to make them cut. I could not make them sharp enough to cut wood at the lathe, even though carbide has long been used for saw teeth. Recently there has been a lot of publicity given to tungsten carbide woodturning tools. They normally have replaceable carbide tips. They are supposedly formulated to be sharper. However, they are apparently less robust than other grades.
Several companies are now selling tipped tools, and users report very favourably. The tools are expensive, and without information about the carbide grade, you have to take the quality on trust. I would like to make some tipped tools with this woodturning grade carbide. I’ve bought some tips from various sources but the ones I have tried so far don’t keep their edge very long when cutting MDF. MDF is very abrasive and hard on sharp edges. A long-lasting edge is the main reason for using carbide. After a bit of use, the carbide edge feels rough to the touch, and like a sawblade when tried with a fingernail,
Yesterday, I bought a micrograin carbide tip from Robert Sorby. I fitted it to one of my homemade tools to try. First impressions are not good. It didn’t do well on MDF, which I turn a lot. Very likely it would work well on ordinary wood though. And at least the tip has a very generous thickness to allow sharpening with a diamond hone.