sprue cutter

[kokomokid]

Anyone have a good method of sharpening the sprue cutter? Most of my alloy has a little antimony and even with a 15-20 second cool down they pull a little chunk when I cut. Looks like a thinner/sharper cutting area will fix the problem?

[Lead pot]

Take a sheet of 600 grid wet sand paper on plate glass and figure 8 it this will sharpen it. It wont do you much good if the hole is to large it will still pull the sprue unless you let the bullet cool.