Make a pattern for moulding(part 1)

Theory:

       The pattern is a model made of suitable material and is used for making the cavity in moulding sand or other suitable mould materials. It has been said that a poor casting may be produced from a good pattern, but a good casting will not be made from a poor pattern. Most patterns are made of wood because of its cheapner, case of availability, lightness, case of obtaining smooth surface and preserving surface by applying coating of shellac, ability to be worked on easily. To make a pattern we worked in workshop. The design should be as simple as possible to make the pattern.

Tools Required:

       We used the following tools for making a pattern.

1.     Smooth planer

2.     Tri-square

3.     Chisel

4.     Wooden mallet

5.     Divider

6.     Making gauge

7.     Steel scale

8.     Tenon saw

9.     Working place or table

Discussion of Tools:

                                 1. Smooth Planer:

We used planer for getting flat smooth surface of the pattern. The planer blade is very sharp.

                                                      Figure: planer

                                2. Tri-Square:

For setting out and testing all corners and ends which should be at right angle, we used a tri-square.

                                                      Figure: Tri-square

                            3. Chisel:

Some small and large firmer chisels are used in workshop. We used chisel for removing the wood from the timber.

              

                                                             Figure: chisel

                      4. Wooden Mallet:

It is only used in workshop. It is one kind of hammer but is made of wood. To remove the wood from the timber by using chisel, we used wooden mallet to give force on chisel.

                                         

                                                        Figure: Wooden Mallet

                    5. Marking Gauge:

It is one kind of marking tool which is used for making lines parallel to the edge of the job. It has a stem and head, usually made of beach and a marker. In setting it, the head is set to the required position, measured from the point of spur and the screw is partially tightened.

                                            Figure: Marking Gauge