1. Toolholders and Toolholding for the Lathe
MACH 118: Lathe & Mill I
Thaddeus Stevens College of Technology

2. Introduction TOOLHOLDERS/TOOLHOLDING FOR THE LATHE
For lathe work, cutting tools must be supported and fastened securely in the proper position to machine the workpiece.
There are many different types of toolholders available to satisfy this need.
Anyone working with a lathe should be able to select the best toolholding device for the operation performed.
Created by R. Schwartz 10/04/08

3. OBJECTIVES OBJECTIVES:
Identify standard, quick-change, and turret-type toolholders.
Identify toolholding for the lathe tailstock.
Created by R. Schwartz 10/04/08

4. Toolholding for the Lathe Carriage
TOOLHOLDERS/TOOLHOLDING FOR THE LATHE
Toolholding for the Lathe Carriage
An important aspect of lathe toolholding is rigidity.
If tool bits or inserts are not well supported or overhang is too great, vibration & tool chatter will often be the result.
Tool posts are mounted on the compound rest and held securely by a T-bolt.
The most commonly used are the quick-change types, more versatile than the standard post.
Fig. I-48 Quick-change tool post, dovetail type.
Created by R. Schwartz 10/04/08

5. Toolholding for the Lathe Carriage
TOOLHOLDERS/TOOLHOLDING FOR THE LATHE
Toolholding for the Lathe Carriage
The tool post shown here uses double vees to locate the toolholders, which are clamped and released from the post by turning the top lever.
Fig. I-49 Quick-change tool post.
Created by R. Schwartz 10/04/08

6. Toolholding for the Lathe Carriage
TOOLHOLDERS/TOOLHOLDING FOR THE LATHE
Toolholding for the Lathe Carriage
The quick change tool post (Aloris) has replaced
the now obsolete “rocker” type tool post.
Created by R. Schwartz 10/04/08

7. Toolholding for the Lathe Carriage
TOOLHOLDERS/TOOLHOLDING FOR THE LATHE
Toolholding for the Lathe Carriage
Toolholders for the quick- change tool posts are made in many different varieties to accommodate various machining ops.
Created by R. Schwartz 10/04/08

8. Toolholding for the Lathe Carriage
TOOLHOLDERS/TOOLHOLDING FOR THE LATHE
Toolholding for the Lathe Carriage
A boring bar toolholder in use; the boring bar is rigidly supported.
Fig. I-54 Boring toolholder. This setup provides good boring bar rigidity (Aloris Tool Technology)
Created by R. Schwartz 10/04/08

9. Toolholding for the Lathe Carriage
TOOLHOLDERS/TOOLHOLDING FOR THE LATHE
Toolholding for the Lathe Carriage
A cutoff tool mounted in a toolholder.
Created by R. Schwartz 10/04/08

10. Toolholding for the Lathe Tailstock
TOOLHOLDERS/TOOLHOLDING FOR THE LATHE
Toolholding for the Lathe Tailstock
A tailstock spindle used to hold Morse taper shank tools
Fig. I-62 Taper shank drill with sleeve ready to insert in tailstock spindle.
Created by R. Schwartz 10/04/08

11. Toolholding for the Lathe Tailstock
TOOLHOLDERS/TOOLHOLDING FOR THE LATHE
Toolholding for the Lathe Tailstock
One of the most common toolholding devices used on a tailstock is the drill chuck
Used for holding straight shank drilling tools.
Fig. I-63 Drill chuck with Morse taper shank
Created by R. Schwartz 10/04/08

12. Toolholding for the Lathe Tailstock
TOOLHOLDERS/TOOLHOLDING FOR THE LATHE
Toolholding for the Lathe Tailstock
When a series of operations must be performed and repeated on several workpieces, a tailstock turret can be used.
The tailstock turret shown has six tool positions.
One is used as a workstop.
The other positions are for center drilling, drilling, reaming, counterboring, and tapping.
Fig. I-64 Tailstock turret.
Created by R. Schwartz 10/04/08

13. REVIEW Name two different types of toolposts used on engine lathes.
Which type of toolpost has become obsolete and is rarely used in industry?
State some advantages of the quick change toolpost.
What type of taper is found in the tailstock spindle?
Created by R. Schwartz 10/04/08