Fig. 2 shows the assembly of a Gib and Cotter Joint. Disassemble the parts correctly and then draw to scale 1:1, its following views of the following components. Keep their position same with respect to both H.P. and V.P.
(i) STRAP: (a) Front view lower half in section, (b) Top view. (ii) GIB: (a) Front view, (b) Top view. Print the titles of both and the scale used. Draw the projection symbol. Give 6 important dimensions.
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To ensure accuracy when disassembling, do not change the spatial orientations! Always keep the components aligned horizontally or vertically exactly as they were arranged in the original assembly drawing.
Step 1: Understanding Gib and Cotter Joint Assembly Proportions:
The Gib and Cotter Joint joins two co-axial square rods of section $30\text{ mm} \times 30\text{ mm}$.
• Strap (Fork End): • It wraps around the eye end of the other rod. The internal gap matches the rod depth, which is $30\text{ mm}$.
• Thickness of each strap limb is $12\text{ mm}$.
• Total outside height at the fork = Inside width ($30\text{ mm}$) + $2 \times$ thickness ($12 + 12$) = $54\text{ mm}$.
• Width in top view = Width of square rod = $30\text{ mm}$.
• Length of the parallel strap portion up to the transition step = $38 + 40 + 25 = 103\text{ mm}$.
• The rectangular slot in the strap has a width of $40\text{ mm}$ and a total height passing through both limbs.
• Gib (10 Thick): • Thickness = $10\text{ mm}$. Width = $30\text{ mm}$ (matches the strap width).
• Inner profile height = Outside height of strap loop = $54\text{ mm}$.
• Two projection hooks (lips) of height $12\text{ mm}$ and length $12\text{ mm}$ keep the strap from spreading open.
• Overall height of the Gib = $54 + 12 + 12 = 78\text{ mm}$.
Step 2: Drafting Instructions for Disassembled Components: Component (i): STRAP (Strap/Fork End) • (a) Front View, Lower Half in Section:
Draw the symmetric profile of the Strap fork. Symmetrically divide it along the horizontal axis.
In the unsectioned top half, show the outer solid outline of the upper limb (thickness $12\text{ mm}$) and the rectangular cotter slot through it.
In the sectioned bottom half, the lower limb of thickness $12\text{ mm}$ is cut. Apply uniform cross-hatching at $45^{\circ}$ through the solid metal area. The slot of width $40\text{ mm}$ located at $38\text{ mm}$ from the inner shoulder step remains completely open and unhatched.
• (b) Top View:
Draw a plain rectangular outline of size $103\text{ mm} \times 30\text{ mm}$. Show the cotter slot of size $40\text{ mm} \times 30\text{ mm}$ as a solid rectangle of heavy lines, situated at $25\text{ mm}$ from the left open end.
Component (ii): GIB • (a) Front View:
Draw the profile of the Gib. The overall height is $78\text{ mm}$ and thickness is $10\text{ mm}$. The left outer face is straight and perpendicular. The inner face on the right (facing the cotter) is tapered at a slope of 1 in 30. Show two horizontal lip projections at the top and bottom of size $12\text{ mm} \times 12\text{ mm}$ extending to the left.
• (b) Top View:
A simple rectangular shape of size $30\text{ mm} \times 10\text{ mm}$ representing the plan view of the Gib.
