What is the difference between carbide and high speed steel tools?
The two materials from which most cutting tools are made are carbide and high speed steel (HSS). While there are a vast number of classifications and metallurgical variations within each material, the most common grades used for rotary cutting tools such as engraving cutters are C-2 micrograin carbide and M2 HSS.
Carbide is an extremely hard and abrasion resistant material and is recommended for most typical engraving applications. While it is slightly more expensive than HSS, it can out last it by a factor of 5-10 times depending upon the application. It can be used very effectively on both plastic and metal and is the most cost-effective choice of engraving tools.
While HSS doesn't have the wear and life characteristics of carbide, it does tend to be more resilient and less brittle and is the best choice for deep cuts with small tip sizes in harder materials. Engraving seal dies which are typically done to a depth of .035"-.040" with a .007"-.010" tip is a good example.
One consideration in selecting which type of tool to use is whether or not you do your own sharpening. Carbide tools last a long time before becoming dull, but are more considerably more difficult to resharpen. Achieving a perfect cutting edge requires the use of a properly dressed and trued diamond grinding wheel of between 400 and 600 grit.
HSS tools do not last nearly as long as carbide ones, however they are much easier to sharpen for the average user. They are generally sharpened using aluminum oxide grinding wheels in the 80 to 100 grit range. Since these wheels are relatively soft, they can be easily trued and dressed with the diamond dressing attachment which is an integral part of most cutter grinders.
If you do not do your own sharpening, carbide tools are by far the best choice for the majority of typical engraving applications.
