Ken There are many grades of carbide, each designed for a specific purpose. Who knows what grade the cheapos are? Could be anything the vendors picked up cheaply because it is not a particularly popular grade for the professionals. Regards Dave Saudi-Arabia-On-Sea --- KJones9154@xxxxxxx wrote: > The tips are very sensitive to intermittent shocks such as when turning a > round from an irregular shaped blank. > Out of a set of 5 tools, each with a 3 sided replaceable tip, almost all of > the cutting edges have chipped off and I can no longer use them. ___________________________________________________________ To help you stay safe and secure online, we've developed the all new Yahoo! Security Centre. http://uk.security.yahoo.com MODEL ENGINEERING DISCUSSION LIST. To UNSUBSCRIBE from this list, send a blank email to, modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject line.