12) What is called, the extra material provided on material for the preparation of the edges and seams?

13) Which type of joint consists of a folded section that inter locks with folds on articles to be joined and can be dismantled?

14) What is to be done for the surplus wire of the wired edge?

15) What is process which makes sheet metal stronger and rigid?

16) What is the distance from notch to edge of the sheet in wired notch?