1. BASIC TEORY OF LATHE OPERATION
Sumariyanto: 2007
BASIC TEORY OF LATHE OPERATION

2. LEARNING ACTIVITIES
After following this study, student must be able to:
Prepare lathe equipments
Set lathe equipment according to procedure
Use lathe equipment according to procedure
Understand the lathe operation according to procedure
Calculate the cutting speed mathematically
Calculate speed of machine rotation mathematically
Set the feed rate according to procedure
Lathe operation according to procedure

3. PARTS OF LATHE
Franklin W Olin: 2005

4. Basic Theory of Lathe Operation
Turning principle is to make the circular object with the certain diameter by cutting.

5. LATHE OPERATION

6. LATHE OPERATION
Turning : to produce straight, conical, curved, or grooved work pieces
Facing : to produce a flat surface at the end of the part or for making face grooves.
Boring : to enlarge a hole or cylindrical cavity made by a previous process or to produce circular internal grooves.
Drilling : to make a hole by fixing a drill in the tailstock
Threading : to make external or internal threads
Knurling : to make a regularly shaped roughness on cylindrical surfaces

7. WORK HOLDING

8. KINDS AND FUNCTION OF CHUCK
- For holding cylindrical stock centered.
- For facing/center drilling
Three Jaw Chuck
This is independent chuck ; generally has four jaws , adjusted individually on the chuck faced by means of adjusting screws
Four Jaw Chuck
Sumariyanto. 2007

9. KINDS AND FUNCTION OF CHUCK
Collet chuck is used to hold small workpieces
Collet Chuck
Thin jobs can be held by means of magnetic chucks.
Magnetic Chuck
www. engbasics.com www. efunda.com

10. PREPARE LATHE EQUIPMENTS
1. Lathe 2. A set of chuck 3. A set of tools post 4. Cutting tool 5. Measuring tools 6. Inspection equipment work piece

11. SETTING LATHE EQUIPMENTS
Procedure Opening Chuck

12. SETTING LATHE EQUIPMENTS
Procedure Installing Chuck

13. INSTALL THE WORK PIECE AT CHUCK
Nipping Work Piece at External Diameter
Nipping Work Piece at Inside Diameter

14. USING EQUIPMENT ACCORDING TO PROCEDURE
Installing The Work Piece At Chuck

15. CHECKING THE PLAIN OF WORK PEACE
Checking Plain with the Scribel Control
Controlling Plain by Dial Indicator

16. HOLDING WORK PIECE (VIDEO)

17. CHECKING THE PLAIN OF DRILL (VIDEO)

18. INSTALLING AND CHECKING CUTTING TOOLS
Too High.
Too Low
As High As Center

19. DETERMINE OF FEEDING PARAMETER
Cutting Speed (Vc/Cs)
Vc : Cutting speed (M/minute)
n : Axis rotation speed (RPM)
D : Diameter (mm)
1/1000 :1 mm = 1/1000 m

20. CUTTING SPEED Tables of Cutting Speed For a Few Material Type
Materials
HSS
Carbide
Fine
Coarse
Tool Steel
75 – 100
25 – 45
185 – 230
110 – 140
Low Carbon Steel
70 – 90
25 – 40
170 – 215
90 – 120
Medium Carbon Steel
60 – 85
20 – 40
140 – 185
75 – 110
Cost Iron
40 – 45
25 – 30
60 – 75
Brass
45 – 70
185 – 215
120 – 150
Alumunium
70 – 110
30 – 45
140 – 215
60 – 90

21. SPEED OF MACHINE ROTATION
example: If we will fit the work piece from material of alumunium diameter 40 mm with the HSS. Calculate main axis rotation speed! Answer: Cutting speed of visible aluminum at table 4.1 for example we take 30 m/ minute. So that its speed is:

22. FEED RATE Feed Rate Types
Coarse Turning:
Uses the thickness feeding 0,40 mm for the work piece which do not need the high precision.
2. Smooth Turning:
Uses the thickness feeding (0,07-0,12) mm
for the work piece of needing high precision.

23. Tables Of Feed Rate To All Kinds Of Materials With The Cutting Tool (HSS).
Coarse Turning
Smooth Turning
inchi mm
Inchi
Alumunium
0,015-0,030
0,40-0,75
0,005-0,010
0,13-0,25
Bronze.
0,015-0,025
0,40-0,65
0,003-0,010
0,07-0,25
Cast Iron
0,005-0,012
0,13-0,30
Tool Steel.
0,010-0,020
0,25-0,50
Machinery Steel.

24. BASIC THEORY OF DRILLING
Drilling is to make the hole with the drilling tool
Drilling

25. STEPS OF DRILLING USING LATHE
Drill the work piece using center drilling
Sett the position of tail stock
Chuck the working pieces
Arrange the spindle speed
Install the drill at tail stock
Operate the drilling at working pieces
Determine of hole depth
Finish the drilling process

26. SINGLE THREAD
Basic Theory of Single Thread Single thread is the condition when one circle the work pieces only has one thread path.

27. KINDS OF THREAD PROFILES
Triangle Thread
Trapezium Thread
Buttress Thread
Radius Thread
Rectangle Thread

28. Steps Of Thread Turning
Determine lathe type to get the thread of pitch wanted
Provide the working pieces according to major diameter thread
Install the working pieces correctly
Set tool of thread and top carriage correctly
Determine pitch by arranging handle at gearbox
Kalpakjian
Determine the cutting speed, is usually selected by 1/3 from cutting speed is common turning.
Calculate the depth of thread cutting
Give the long limitation part of working pieces will be threaded
Check the result of corect thread pitch with thread picth gauge
Do thread cutting correctly.
Check the thread which has been made.

29. LATHE OPERATION (VIDEO)

30. Cutting Off Steps of Cutting Off Chuck the working pieces correctly
Estimate part that will be cut by closest chuck
Cut it manual or automatically
Cutting Off

31. REFERENCES Book work shop Technolgy by Hajra choudry
Advances in Manufacturing Technology C.J Thomas
DeGarmo: E.P. DeGarmo et al, Materials and Processes in Manufacturing, Wiley, 2003.
Franklin W Olin: Engine Lathe Introduction. College of Engineering.
Sumariyanto Bubut Dasar. Malang: PPPPGT Malang
Website
www. engbasics.com
www. efunda.com
Kalpakjian:

32. THANK YOU
PRESENTED BY
Herianto
SMKN 1 PUNGGING