Rod Joints

Given: Detail (part) drawings of a Sleeve and Cotter Joint. All rounds and fillets = R4. Scale 1:1.

Concept: A Sleeve and Cotter Joint connects two co-axial rods end-to-end. The sleeve is a hollow cylinder that fits over the spigot ends of both rods; cotters are driven through transverse slots to lock the assembly.

Step-by-step procedure for Assembly Drawing:

Step 1 – Identify the parts from the detail drawings:
- Two rods (Rod A and Rod B) with spigot ends having cotter slots.
- One sleeve (hollow cylinder) with two cotter slots.
- Two cotters (tapered flat wedges).

Step 2 – Establish the principal axis:
Place the common axis of the rods and sleeve horizontal, parallel to V.P. (so the front view shows the full length).

Step 3 – Draw the Front View (lower half in section):
1. Draw the centre line (horizontal axis) of the assembly.
2. Draw the outer profile of the sleeve (rectangle representing the outer cylinder) symmetrically about the axis.
3. For the lower half in section: the lower half is cut by a horizontal cutting plane passing through the axis.
- Show the cross-hatching (section lines at 45°) on the cut surfaces of the sleeve and the rod spigot ends.
- The upper half remains as an external (outside) view showing hidden lines where necessary.
4. Show the two rods entering the sleeve from both ends; their spigot ends are visible inside the sleeve in the sectioned lower half.
5. Show the two cotters in their respective slots — cotters appear as rectangles in the front view; apply section lines to the cotter cross-sections.
6. Show taper of cotters (typically 1:30 or as given in detail drawing).
7. Mark all rounds and fillets as R4.
8. Add centre lines, dimension lines, and 6 important dimensions (e.g., rod diameter $\phi d$, sleeve outer diameter $\phi D$, sleeve length $L$, cotter width $w$, cotter thickness $t$, slot width).

Step 4 – Draw the Left Side View:
1. Project from the front view to the right (left side view is placed to the right of the front view in first-angle projection).
2. The left side view shows the end face of the sleeve as a circle (outer diameter $D$) with a concentric circle (inner diameter = rod diameter $d$).
3. The cotter slot appears as a rectangle across the circular face.
4. Show the rod end as a circle of diameter $d$ inside the sleeve bore.
5. Add centre lines.

Step 5 – Finishing:
- Write title block: SLEEVE AND COTTER JOINT.
- Write scale: 1:1.
- Draw the first-angle projection symbol.
- Give 6 important dimensions.

Key dimensions to mark (typical for standard sleeve and cotter joint):
$$d = \text{rod diameter},\quad D = 2d,\quad L_{\text{sleeve}} = 8d,\quad \text{cotter taper} = 1:30,\quad w_{\text{cotter}} = 1.5d,\quad t_{\text{cotter}} = 0.4d$$

Result: The assembled front view (lower half in section) and left side view are drawn to scale 1:1 as per first-angle projection.

Given: Assembly drawing of a Sleeve and Cotter Joint (Fig. 4.8 — Front View and Top View). Scale 1:1. First-angle projection.

Concept: Disassembly means separating individual parts from the assembly and drawing their individual orthographic views, keeping the same orientation (position w.r.t. V.P. and H.P.) as in the assembly.

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(a) SLEEVE

Step 1 – Identify the sleeve in the assembly:
The sleeve is the outer hollow cylindrical part. From the assembly front view and top view, read off all dimensions of the sleeve: outer diameter $D$, inner diameter (bore) $d$, total length $L$, cotter slot dimensions (width $w$, height $h$, position from ends).

Step 2 – Front View, upper half in section:
1. Draw the horizontal centre line.
2. Draw the outer rectangle (length $L$, height $= D$) representing the outer cylinder.
3. Upper half in section: A horizontal cutting plane through the axis cuts the upper half.
- Upper half: show the internal bore as two horizontal lines at distance $d/2$ from the axis; apply 45° cross-hatching to the cut material (sleeve wall).
- Lower half: show as external view with hidden lines (bore shown as dashed lines).
4. Show the two cotter slots as rectangular cut-outs through the sleeve wall in the upper half section.
5. Mark all rounds and fillets R4 at internal corners.
6. Add centre lines and dimensions.

Step 3 – Side View, looking from left:
1. Project from the front view.
2. Draw the end circle of the sleeve: outer circle diameter $D$, inner circle (bore) diameter $d$.
3. Show the cotter slot as a rectangle across the circular face (if the slot is at the end region).
4. Add centre lines.

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(b) COTTER B

Step 1 – Identify Cotter B:
Cotter B is one of the two flat tapered wedges. From the assembly, read its length $l_c$, width $w_c$, thickness $t_c$, and taper (typically 1:30 on one face).

Step 2 – Front View of Cotter B:
1. Draw the front view as a flat rectangle (length $l_c$ × width $w_c$).
2. Show the taper: one long edge is straight (horizontal), the other is inclined to give the taper ratio (e.g., 1:30).
3. Show the head (if any) at one end.
4. Add centre line and dimensions.

Step 3 – Side View of Cotter B:
1. Project from the front view.
2. The side view shows the thickness $t_c$ as a rectangle (width $w_c$ × thickness $t_c$).
3. Add dimensions.

Finishing:
- Title: SLEEVE AND COTTER JOINT — DISASSEMBLED PARTS.
- Scale: 1:1.
- First-angle projection symbol.
- Give 6 important dimensions across all views.

Result: Individual orthographic views of the Sleeve (front view upper half in section + left side view) and Cotter B (front view + side view) are drawn to scale 1:1.

Given: Assembly drawing of Sleeve and Cotter Joint (Fig. 4.9). Scale 1:1. First-angle projection.

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(a) SLEEVE

Step 1 – Read sleeve dimensions from assembly:
Outer diameter $D$, bore diameter $d$, total length $L$, cotter slot width $w$, slot height $h$, distance of slot from each end.

Step 2 – Front View, lower half in section:
1. Draw horizontal centre line.
2. Draw outer profile (rectangle $L \times D$).
3. Lower half in section: Cutting plane through the axis exposes the lower half.
- Lower half: show internal bore (two lines at $\pm d/2$ from axis), apply 45° hatching to sleeve wall material.
- Upper half: external view; show bore as hidden (dashed) lines.
4. Show cotter slots as rectangular openings through the sleeve wall in the lower half section.
5. Mark R4 fillets at all internal corners.
6. Add centre lines and dimensions.

Step 3 – Side View, looking from right:
1. In first-angle projection, the right side view is placed to the left of the front view.
2. Draw the right end face of the sleeve: outer circle $\phi D$, inner circle $\phi d$.
3. Show cotter slot as a rectangle.
4. Add centre lines.

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(b) ROD A

Step 1 – Identify Rod A:
Rod A has a main cylindrical body (diameter $d$, length as given) and a spigot end that fits inside the sleeve. The spigot end has a cotter slot (width $w$, height $h$).

Step 2 – Front View of Rod A:
1. Draw the main rod body as a rectangle (diameter $d$, length $l_1$).
2. Draw the spigot end (same diameter $d$ or reduced, length $l_2$) extending from the main body.
3. Show the cotter slot as a rectangular cut-out through the spigot.
4. Show the collar (if present) between the main body and spigot.
5. Add centre line, hidden lines for internal features, and dimensions.

Step 3 – Side View of Rod A, looking from right:
1. In first-angle projection, place to the left of the front view.
2. Show the circular cross-section of the rod: circle $\phi d$.
3. Show the cotter slot as a rectangle across the circle.
4. Add centre lines and dimensions.

Finishing:
- Title: SLEEVE AND COTTER JOINT — DISASSEMBLED PARTS.
- Scale: 1:1.
- First-angle projection symbol.
- Give 6 important dimensions.

Result: Individual views of Sleeve (front view lower half in section + right side view) and Rod A (front view + right side view) drawn to scale 1:1.

Given: Detail drawings of parts of a Spigot and Socket Joint (Fig. 4.13): Socket (M.S.) 1-off, Spigot (M.S.) 1-off, Cotter (M.S.) 1-off. Scale 1:1.

Concept: In a Socket and Spigot Cotter Joint, the spigot (male part) fits into the socket (female part). A cotter is driven through aligned transverse slots in both parts to lock them together.

Step-by-step Assembly Drawing Procedure:

Step 1 – Identify parts and read dimensions:
- Socket: Hollow cylindrical part with a collar; has a cotter slot near the open end. Read: outer diameter $D_s$, bore diameter $d_s$, collar diameter $D_c$, total length $L_s$, slot dimensions.
- Spigot: Solid rod with a spigot end that fits into the socket bore; has a cotter slot. Read: rod diameter $d_r$, spigot diameter $d_s$ (= socket bore), spigot length, slot dimensions.
- Cotter: Flat tapered wedge. Read: length $l_c$, width $w_c$, thickness $t_c$, taper.

Step 2 – Assemble:
Insert the spigot end of the spigot part into the bore of the socket until the cotter slots align. Drive the cotter through the aligned slots.

Step 3 – Front View, lower half in section:
1. Draw the horizontal centre line (common axis).
2. Draw the outer profile of the assembled joint.
3. Lower half in section (cutting plane through the axis, lower half removed):
- Show the socket bore, spigot inside the socket, and the cotter in section.
- Apply 45° hatching to all cut surfaces (socket wall, spigot body, cotter cross-section). Use different hatch angles or spacing for different parts to distinguish them.
- Upper half: external view with hidden lines.
4. Show the collar of the socket and the collar of the spigot (if any) in the external upper half.
5. Show the cotter projecting out on both sides of the joint.
6. Mark R4 fillets at all internal corners.
7. Add centre lines.

Step 4 – Right Side View:
1. In first-angle projection, the right side view is placed to the left of the front view.
2. Project from the front view.
3. Show the end face of the socket as concentric circles ($\phi D_s$ outer, $\phi d_s$ bore).
4. Show the cotter slot as a rectangle.
5. Add centre lines.

Step 5 – Finishing:
- Title: SPIGOT AND SOCKET JOINT.
- Scale: 1:1.
- First-angle projection symbol.
- Give 6 important dimensions.

Key dimensions (typical):
$$d_r = \text{rod dia},\quad D_s = 1.75\,d_r,\quad d_s = d_r,\quad L_s = 3.5\,d_r,\quad w_c = 1.25\,d_r,\quad t_c = 0.3\,d_r$$

Result: Assembled front view (lower half in section) and right side view drawn to scale 1:1.

Given: Assembly drawing of Socket and Spigot Joint (Fig. 4.16). Scale 1:1. First-angle projection.

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(a) SOCKET

Step 1 – Read socket dimensions from assembly:
Outer diameter $D_s$, bore diameter $d_s$, collar diameter $D_c$, collar width, total length $L_s$, cotter slot width $w$, slot height $h$, distance of slot from open end.

Step 2 – Front View, lower half in section:
1. Draw horizontal centre line.
2. Draw outer profile of socket (including collar).
3. Lower half in section:
- Lower half: show the bore as two horizontal lines at $\pm d_s/2$ from axis; hatch the socket wall material at 45°.
- Show the cotter slot as a rectangular opening in the lower half section.
- Upper half: external view; show bore as hidden lines.
4. Mark R4 fillets at internal corners.
5. Add centre lines and dimensions.

Step 3 – Side View, looking from left:
1. In first-angle projection, left side view is placed to the right of the front view.
2. Draw the left end face of the socket: outer circle $\phi D_s$ (or collar $\phi D_c$ if collar is at left end), inner circle $\phi d_s$.
3. Show cotter slot as a rectangle if visible from this end.
4. Add centre lines.

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(b) SPIGOT

Step 1 – Read spigot dimensions from assembly:
Rod diameter $d_r$, spigot end diameter $d_s$ (fits socket bore), spigot length $l_{sp}$, collar diameter $D_{col}$, cotter slot width $w$, slot height $h$.

Step 2 – Front View, upper half in section:
1. Draw horizontal centre line.
2. Draw outer profile of spigot (rod body + spigot end + collar).
3. Upper half in section:
- Upper half: show internal features (if any hollow portion); for a solid spigot, the section shows the solid cross-section with hatching.
- Show the cotter slot as a rectangular cut-out through the spigot end in the upper half.
- Lower half: external view.
4. Mark R4 fillets.
5. Add centre lines and dimensions.

Step 3 – Side View, looking from right:
1. In first-angle projection, right side view is placed to the left of the front view.
2. Draw the right end face of the spigot: circle $\phi d_r$ (rod body end).
3. Show any features visible from the right.
4. Add centre lines.

Finishing:
- Title: SOCKET AND SPIGOT JOINT — DISASSEMBLED PARTS.
- Scale: 1:1.
- First-angle projection symbol.
- Give 6 important dimensions.

Result: Individual views of Socket and Spigot drawn to scale 1:1 as specified.

Given: Assembly orthographic views of a Socket and Spigot Joint (Fig. 4.17 — Front View and Right Side View). Scale 1:1. First-angle projection.

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(a) SPIGOT

Step 1 – Read spigot dimensions from assembly views:
From the front view and right side view of the assembly, identify and record: rod diameter $d_r$, spigot end diameter $d_{sp}$, collar diameter $D_{col}$, collar thickness $t_{col}$, total length of spigot $L_{sp}$, cotter slot width $w$, cotter slot height $h$, distance of slot from spigot end.

Step 2 – Front View, lower half in section:
1. Draw horizontal centre line.
2. Draw the complete outer profile of the spigot (rod + collar + spigot end).
3. Lower half in section (horizontal cutting plane through axis, lower half removed):
- Lower half: show the solid cross-section with 45° hatching.
- Show the cotter slot as a rectangular opening through the spigot end in the lower half.
- Upper half: external view; show hidden lines for the slot.
4. Mark R4 fillets at collar transitions.
5. Add centre lines.

Step 3 – Side View from left:
1. In first-angle projection, left side view is placed to the right of the front view.
2. Draw the left end face of the spigot: circle $\phi d_r$.
3. Show the collar as a larger circle $\phi D_{col}$ (if collar is visible from left).
4. Show cotter slot as a rectangle if visible.
5. Add centre lines.

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(b) SOCKET

Step 1 – Read socket dimensions from assembly views:
Outer diameter $D_s$, bore $d_s$, collar diameter $D_{cs}$, total length $L_s$, cotter slot width $w$, slot height $h$, distance of slot from open end.

Step 2 – Front View, upper half in section:
1. Draw horizontal centre line.
2. Draw the complete outer profile of the socket.
3. Upper half in section (horizontal cutting plane through axis, upper half removed):
- Upper half: show the bore as two horizontal lines at $\pm d_s/2$ from axis; hatch the socket wall at 45°.
- Show the cotter slot as a rectangular opening in the upper half section.
- Lower half: external view; show bore as hidden lines.
4. Mark R4 fillets at internal corners.
5. Add centre lines.

Step 3 – Right Side View:
1. In first-angle projection, right side view is placed to the left of the front view.
2. Draw the right end face of the socket: outer circle $\phi D_s$, inner circle $\phi d_s$.
3. Show cotter slot as a rectangle.
4. Add centre lines.

Step 4 – Finishing:
- Print headings above each view: e.g., "FRONT VIEW — LOWER HALF IN SECTION", "LEFT SIDE VIEW", etc.
- Title: SOCKET AND SPIGOT JOINT.
- Scale: 1:1.
- Draw first-angle projection symbol.

8 Important Dimensions to mark:
$$\text{(1) Rod diameter } d_r,\quad \text{(2) Spigot/bore diameter } d_{sp},\quad \text{(3) Socket outer diameter } D_s$$
$$\text{(4) Collar diameter } D_{col},\quad \text{(5) Total length of socket } L_s,\quad \text{(6) Total length of spigot } L_{sp}$$
$$\text{(7) Cotter slot width } w,\quad \text{(8) Cotter slot height } h$$

Result: Disassembled views of Spigot and Socket drawn to scale 1:1 with 8 dimensions, headings, and projection symbol.

Given: Detail drawings of parts of a Gib and Cotter Joint for square rods (Fig. 4.21): Strap (M.S.) 1-off, Rod (M.S.) 1-off, Gib (M.S.) 1-off, Cotter (M.S.) 1-off. Scale 1:1.

Concept: A Gib and Cotter Joint connects two square (or rectangular) rods. The eye end of one rod fits into the fork (strap) end of the other. A gib and cotter are driven through the slot to lock the joint. The gib prevents the cotter from bending and provides a bearing surface.

Step-by-step Assembly Drawing Procedure:

Step 1 – Identify and read dimensions of all parts:
- Rod: Square cross-section (side $a$), with eye end (rectangular lug with a slot for gib and cotter).
- Strap (Fork): U-shaped part that wraps around the eye end; has a slot for gib and cotter.
- Gib: L-shaped (or flat with a lip) piece placed alongside the cotter.
- Cotter: Flat tapered wedge.

Step 2 – Assemble:
1. Place the eye end of the rod inside the fork (strap).
2. Insert the gib into the slot (gib goes in first, with its lip hooking over the strap).
3. Drive the cotter alongside the gib through the aligned slots.

Step 3 – Front View, lower half in section:
1. Draw the horizontal centre line (axis of the rods).
2. Draw the outer profile of the assembled joint (strap + rod + gib + cotter).
3. Lower half in section (horizontal cutting plane through the axis):
- Lower half: show the internal arrangement — the eye end of the rod inside the strap, the gib and cotter in the slot. Apply 45° hatching to each part with different hatch spacing/angle to distinguish parts.
- Upper half: external view with hidden lines.
4. Show the square rod cross-section in the section.
5. Show the gib lip and cotter taper in the section.
6. Mark R4 fillets at all internal corners.
7. Add centre lines.

Step 4 – Left Side View:
1. In first-angle projection, left side view is placed to the right of the front view.
2. Project from the front view.
3. Show the end face of the strap (fork): the U-shape in end view.
4. Show the square rod cross-section inside the fork.
5. Show the gib and cotter as rectangles in the slot.
6. Add centre lines.

Step 5 – Finishing:
- Title: GIB AND COTTER JOINT.
- Scale: 1:1.
- First-angle projection symbol.

6 Important Dimensions:
$$\text{(1) Square rod side } a,\quad \text{(2) Strap width } B,\quad \text{(3) Strap thickness } t_s$$
$$\text{(4) Cotter width } w_c,\quad \text{(5) Cotter thickness } t_c,\quad \text{(6) Gib thickness } t_g$$

Result: Assembled front view (lower half in section) and left side view drawn to scale 1:1 with 6 dimensions, title, and projection symbol.

Given: Assembly front view of a Gib and Cotter Joint for square rods (Fig. 4.24). Scale 1:1. First-angle projection.

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(1) STRAP (FORK)

Step 1 – Read strap dimensions from assembly:
Overall length $L$, width $B$, fork gap (= square rod side $a$), fork arm thickness $t_f$, slot dimensions for gib and cotter (width $w$, height $h$), distance of slot from end.

Step 2 – Upper half sectional front view:
1. Draw horizontal centre line.
2. Draw the outer profile of the strap (fork) — a U-shaped part in front view appears as a rectangle with a central slot (the fork gap).
3. Upper half in section (cutting plane through axis, upper half removed):
- Upper half: show the internal features — the fork gap, the gib-cotter slot. Apply 45° hatching to the strap material.
- Lower half: external view with hidden lines.
4. Mark R4 fillets at all internal corners of the fork.
5. Add centre lines and dimensions.

Step 3 – Top View of Strap:
1. Project downward from the front view (first-angle projection).
2. The top view shows the plan shape of the strap: a rectangular outline with the fork gap visible as a rectangular slot in the centre.
3. Show the gib-cotter slot as a rectangle across the strap width.
4. Show hidden lines for features below the top surface.
5. Add centre lines.

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(2) GIB

Step 1 – Read gib dimensions from assembly:
The gib is an L-shaped (or flat with a lip/head) piece. Read: length $l_g$, width $w_g$, thickness $t_g$, lip height $h_l$, lip thickness $t_l$.

Step 2 – Front View of Gib:
1. Draw the front view of the gib as seen from the front.
2. Show the L-shape: the flat body (rectangle $l_g \times w_g$) with the lip at one end (or both ends depending on design).
3. Show the taper if the gib has a tapered face (matching the cotter taper).
4. Add centre lines and dimensions.

Step 3 – Top View of Gib:
1. Project downward from the front view.
2. The top view shows the plan of the gib: a rectangle (length $l_g$ × thickness $t_g$) with the lip visible.
3. Add dimensions.

Step 4 – Finishing:
- Title: GIB AND COTTER JOINT — DISASSEMBLED PARTS.
- Scale: 1:1.
- First-angle projection symbol.

6 Important Dimensions:
$$\text{(1) Square rod side } a,\quad \text{(2) Strap overall length } L,\quad \text{(3) Fork arm thickness } t_f$$
$$\text{(4) Gib length } l_g,\quad \text{(5) Gib width } w_g,\quad \text{(6) Gib-cotter slot width } w$$

Result: Individual views of Strap (upper half sectional front view + top view) and Gib (front view + top view) drawn to scale 1:1 with 6 dimensions, title, and projection symbol.

Given: Assembly orthographic views (front view upper half in section) of a Gib and Cotter Joint (Fig. 4.25). Scale 1:1. First-angle projection.

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(a) FORK END

Step 1 – Read fork end dimensions from assembly:
Fork end (strap) dimensions: overall length $L_f$, width $B$, fork gap $g$ (= eye end thickness), fork arm thickness $t_f$, gib-cotter slot width $w$, slot height $h$, distance of slot from fork end.

Step 2 – Front View, lower half in section:
1. Draw horizontal centre line.
2. Draw outer profile of fork end.
3. Lower half in section:
- Lower half: show the fork gap and gib-cotter slot in section; apply 45° hatching to fork material.
- Upper half: external view with hidden lines.
4. Mark R4 fillets. Add centre lines.

Step 3 – Top View:
1. Project downward from front view.
2. Show the plan shape: rectangular outline, fork gap as a slot, gib-cotter slot as a rectangle across the width.
3. Add hidden lines and centre lines.

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(b) EYE END

Step 1 – Read eye end dimensions from assembly:
Eye end (rod with lug): rod cross-section (square side $a$ or circular diameter $d$), eye lug width $w_e$, eye lug height $h_e$, gib-cotter slot width $w$, slot height $h$, total length $L_e$.

Step 2 – Front View, lower half in section:
1. Draw horizontal centre line.
2. Draw outer profile of eye end (rod + eye lug).
3. Lower half in section:
- Lower half: show the solid cross-section of the eye lug and rod; apply 45° hatching.
- Show the gib-cotter slot as a rectangular opening in the lower half.
- Upper half: external view.
4. Mark R4 fillets. Add centre lines.

Step 3 – Top View:
1. Project downward from front view.
2. Show the plan: rod cross-section and eye lug outline; gib-cotter slot as a rectangle.
3. Add hidden lines and centre lines.

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(c) GIB

Step 1 – Read gib dimensions:
Length $l_g$, width $w_g$, thickness $t_g$, lip height $h_l$, taper (if any).

Step 2 – Front View of Gib:
1. Draw the L-shaped profile: flat body with lip at one (or both) end(s).
2. Show taper on one face if applicable.
3. Add dimensions.

Step 3 – Top View of Gib:
1. Project downward.
2. Show the rectangular plan (length $l_g$ × thickness $t_g$) with lip.
3. Add dimensions.

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(d) COTTER

Step 1 – Read cotter dimensions:
Length $l_c$, width $w_c$, thickness $t_c$, taper ratio (e.g., 1:30 or 1:24).

Step 2 – Front View of Cotter:
1. Draw the front view as a flat rectangle ($l_c \times w_c$).
2. Show the taper: one long edge horizontal, the other inclined to give the taper.
3. Show the head (if any) at the wider end.
4. Add dimensions.

Step 3 – Top View of Cotter:
1. Project downward.
2. Show the plan: rectangle ($l_c \times t_c$) with tapered outline.
3. Add dimensions.

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Step 4 – Finishing:
- Print headings above each view:
- "FORK END — FRONT VIEW LOWER HALF IN SECTION"
- "FORK END — TOP VIEW"
- "EYE END — FRONT VIEW LOWER HALF IN SECTION"
- "EYE END — TOP VIEW"
- "GIB — FRONT VIEW", "GIB — TOP VIEW"
- "COTTER — FRONT VIEW", "COTTER — TOP VIEW"
- Title: GIB AND COTTER JOINT — DISASSEMBLED PARTS.
- Scale: 1:1.
- First-angle projection symbol.

6 Important Dimensions:
$$\text{(1) Rod/square side } a,\quad \text{(2) Fork arm thickness } t_f,\quad \text{(3) Eye lug height } h_e$$
$$\text{(4) Gib-cotter slot width } w,\quad \text{(5) Cotter length } l_c,\quad \text{(6) Cotter taper (e.g., 1:30)}$$

Result: All four disassembled parts (Fork End, Eye End, Gib, Cotter) drawn in their respective views to scale 1:1 with headings, 6 dimensions, and projection symbol.