We all know that engineering drawing is language of engineers. So every engineer must be able to read drawing ond decode the information provided at drawing. This exercise enables you to identify the projection system and you will never forget.
Step 1: How to Start
we all know that we have two types of perspective to view object and draw on paper. One is called first angle of projection and another called third angle of projection.
Here is the attached image. You have to look at this image and try to identify the projection system.
Step 2: Lets Take a 3D Object
Imagine a solid cone. Keep it in a vertical position or horizontal position as shown in image.
Look at the vertical position of cone. Now look at the cone from the top and bottom. What would you see?
Look at the horizontal position of cone. Now look at the cone from the right and left. What wolud you see ?
Step 3: View Placement
Now what whatever you have that would be a bigger base circle and two concentric circle, the question is where you will place those views. The views placement will decide the projection system that wether you seeing oblect in first angle projection or you seeing in third angle projection.
Step 4: How to Place Views
please see the video carefully for view placement.
Step 5: Difference Between First Angle and Third Angle
please see the attached video and image.
Step 6: Excercise for You
complete this exercise