Centre Lathe

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Centre Lathe
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Centre line of Workpiece
Headstock
Three Jaw Chuck
Tailstock
Toolpost
Compound Slide
Saddle
Bed
Cross Slide
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Three Jaw Chuck
Toolpost
Compound Slide
Saddle
Bed
Cross Slide
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Workpiece materials normally used are Aluminium,
Brass and Mild Steel.
The Round Bar is placed in the Three Jaw chuck.
The chuck centralises the Workpiece.
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Three Jaw Chuck
Each of the jaws can be reversed to hold larger
objects.
Chuck key.
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Tools
Before work is started it is important that the
Lathe tool is centred. The tip of the Lathe tool
should be the same height as the tip of the
tailstock centre.
Round Nose Tool for rough work
Parting Off Tool for rough work
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Processes Facing Off
Facing off
This is a process of squaring off the end of the
piece of steel.
This is achieved by turning the cross slide
handle which moves the cross slide and the
cutting tool over the surface of the steel.
You will only be removing approximately 1mm of
material.
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Processes - Drilling
First a Countersink bit is used to drill slightly
into the material. This creates a hole for the
Twist drill bit to get started in.
The twist Dill bit stays static as the material
turns.
The hole is only enlarged at 2mm at a time to
prevent it over heating then jamming.
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Processes - Knurling
Knurling is a process where a textured grip is
added.
A very slow speed is used for this process.
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Processes Parallel Turning
Parallel Turning
Using the saddle handle the Compound Slide is
moved along the work piece.
The majority of the material is removed by the
Round Nose tool then finished with a Lathe tool.
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Processes Chamfer
Chamfer
Chamfer is the removal of a dangerous corner to
an angle of 45 degrees.
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Processes Parting Off and Taper Turning
The top slide is set to the required angle. The
top slide handle is turned moving the cutting
tool into the steel at the required angle.
Taper Turning
After one pass the top slide is retracted. The
cross-slide handle is then turned to move the
tool 1mm closer. The Top slide handle is turned
again for another pass.
Note that removal of more than 1mm can be to much
and leave a poor finish.
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Processes Parting Off and Taper Turning
After one pass the top slide is retracted. The
cross-slide handle is then turned to move the
tool 1mm closer. The Top slide handle is turned
again for another pass.
Parting off
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Centre Lathe Processes
The name given to the curled waste material is
SWARF. Care must be taken when handling as it is
razor sharp.
Watch for the happy bearded man !
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A micrometer is a precision measuring instrument
used by engineers. Each turn of the handle moves
the Spindle 0.5mm towards the Anvil Face.
Once the object is trapped in between the Anvil
Face and the and the Spindle face the measurement
can be read.
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Turning Processes
Facing Off
Knurling
Parallel Turning
Parting Off
Chamfer
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Three Jaw Chuck
Tool Post
Tailstock
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Micrometer