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                                                            PATTERN SHOP

In the case of casting machine parts, pattern is necessary. Pattern shop is more useful in the foundry process. Pattern is the main factor for the foundry process. Wood is the most useful material as a pattern. Because its process is easy and cost is limited in few amount. It is also available and get easily as demand.

Pattern material :
                                   The common materials used in pattern making include. Such as – wood, metal, plastic and quick setting component.
    (1)Wood : It should be straight gained and free from rusts. It has following advantage-
           * Light in weight
           * Inexpensive can be repaired easily
           * Good work ability
           * Holds well varnishes and paints
   (2)Metal : A metal pattern can be either cast from a master wooden pattern or may be machined by usual method as machining. It has following advantage-
           * More accurate in size than wooden pattern
           * Have a smooth surface
           * Do not deform in storage
           * Have high resistance to wear, abrasion, corrosion
           * Can withstand rough handling
(3)Aluminum alloys : In foundry shop aluminum alloys is used to made pattern. It has some following advantage-
           * Good machinability
           * High corrosion resistance
           * Low density
           * Good surface finish
It has following disadvantage-
            * Low strength
           * High cost

Types of pattern :
                            There are various types of pattern depending upon the complexity of the job, the number of casting required and the molding procedure adopted. There are –
1.      Single piece pattern
2.      Split pattern or two piece pattern
3.      Gated pattern
4.      Cope and drag pattern
5.      Match plate pattern
6.      Loose piece pattern
7.      Follow board pattern
8.      Sweep pattern
9.      Skeleton pattern
In BITAC pattern shop the following machine are available-
1.      Wood planer and thickness machine
2.      Wood jointer machine
3.      Wood turning lathe
4.      Circular saw
5.      Band saw
6.       Jig saw
7.      Disc sander
8.      Bobbin sander
9.      Blade welding machine
10. Grinding machine
11. Drill machine
12. Mortizer machine
1)Wood planer and thickness machine :      It is used to lower surface finishing.

It is possible to Planning any thickness of wood.
2)Wood jointer machine :   It is used to joint wood.
3)Wood turning lathe :     It is used to taper cutting.
4)Circular saw &Band saw :   It is used cutting wood is various size.
5)Jig saw :  It is used to cutting latter. It is also used to cutting small design.
6)Disc sander :  It is used to finishing outside surface of wood.
7)Bobbin sander :  It is used to finishing inside surface of wood.
8)Drill machine :    It is used to cutting drill.
9)Mortizer machine :   It is used to cutting different type of group.
Different types of hand tools :
1.      Hand planer
2.      Hand saw
3.      Divider
4.      Outside calipers
5.      Inside calipers
6.      Chisel
7.      Hammer
8.      Try square
9.      Princer
10. Sciber
11. Cut pencil
12. Screw driver
13. Marking gage
14. Wooden file


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