Smithy Midas 1220 LTD - Manual (Page 41)

Chapter 9
Setting Up Lathe Tools
After selecting a cutter, insert it in the toolholder. Allow the cutter bit to project just
enough to provide the necessary clearance for the cutting point. The closer the cutter is
to the toolpost, the more rigid the cutting edge. Allen-head capscrews hold the tool in the
toolpost. To assure maximum rigidity, don't let the tool extend too far beyond the end of
the toolpost turret.
Cutting Tool Height
After inserting the cutting tool into the toolpost, adjust the height of the cutting edge in
relation to the lathe center. Insert a center in the tailstock. Then run the tool and center
together.
The cutting edge on the tool should meet the point on the center. It may be necessary
to use shims, which can be of various thicknesses and materials (Figure 9.1). Many
seasoned cutting-tool height machinists use pieces of old hacksaw blades as shims. If the
toolbit is too high, shim the back of the toolbit. If it's too low, shim the entire tool.
Figure 9.1 Placing shims under the tool can correct cutting too height.
Turning Tools
For general turning operations, set the point of the cutter bit slightly above the
centerline of the work. In steel, the harder the material, the less above center (Figure
9.2, left).
Exceptions are soft brass, aluminum, and materials that tend to pull or tear. When
machining these materials, set the cutter on dead center (Figure 9.2, right).
9-1 Or Visit www.smithy.com