Re: Small problem turning brass
As a general rule I try to turn the smaller diameter first both to minimize burring and also to maintain the rigidity of the part. In other words if you were turning the whole thing down to 1/4" (6.35mm) diameter and then went back to reduce the diameter at the end often there isn't enough strength in the 1/4" (6.35mm) portion to hold the part rigidly. It may deflect instead of cut causing tapers, chatter and otherwise poor finish. Also, when you reach the shoulder on the last pass it is good practice to back the tool straight out from the part creating a nice flat and clean surface on the face of the shoulder. One last thing I want to point out is that most carbide insert lathe tools have a 60 deg. angle at the cutting edge and you should usually have it turned so that the cutting face of the insert has a slight angle away from the face you are cutting to thus leaving a small bit of stock on the part to skim off as you back the tool away from the part.
Moldmaker extraordinaire running many machines at B&D Machine, Inc. Tolland, CT.