I find that locking my carriage is an essential step to take in order to maximize rigidity. Keep in mind that parting off is a fairly demanding operation on any lathe. Notice there is a lot of positive back rake on the tool as well as plenty of side relief. This was on a 1/4″ blank and it probably took me a good 15 to 20 minutes of grinding to get it right. You have to remove more material to make a parting tool than most any of the other blade types. A thinner parting tool would have been better. It is about 1/8″ wide, which is pretty wide. I ground one parting tool from HSS-Cobalt, which is shown above. These parting tools are generally thin blades of HSS, but there are also carbide insert parting tools available for the task or you can grind a cutoff tool out of HSS. Parting or cutoff is the operation of cutting a piece off by slicing a groove all the way through it with a special parting tool or cut off tool. Lathe Parting Tool & Cut Off Tool: Tips & Techniques
