Fender Design

FENDER :

1.Front Fender

• Fender is the American English term for the part of an automobile, motorcycle, or other vehicle body that frames a wheel well (the fender underside). Its primary purpose is to prevent sand, mud, rocks, liquids, and other roads spray from being thrown into the air by the rotating tire. Fenders are typically rigid and can be damaged by contact with the road surface.

• When a vehicle is moving, the tire picks up stones and others and hurls them in all directions. Fenders are basically present to prevent any injuries to pedestrians and contain the motion of these particles.

2.Front Fender Types

• The front fender has two types which are full fender type and half fender type.
• Full fender is first invented and used fender type. It uses more material while manufacturing.
• Half fender type has been used by all the automobiles present now. It uses very little material as compared with the full fender type. Hence it is lightweight in construction. By reducing the weight, the inertia required to overcome the car will be reduced. Hence, eventually, engine performance will increase.
• While manufacturing the fender, it is possible to make two half fenders with the same material, which is used to make a full fender. The below image shows the material sheet having full fender as well as a half fender.

3.FENDER MOUNTINGS

• The fender has five mountings which are drip, A-pillar, sill, bumper, and baffle. The below image shows the location of the mountings.

4.Drip Mounting

• It's an important and critical mounting in fender design.

• For placing the headlamp we have to leave a minimum of 150 mm from the front.
• While designing the drip mounting we have to leave a 200-300 mm distance for the cowl top.

• A cowl is a panel that covers the gap between your car's hood and windshield.
• It supports both the windshield and the dashboard while also protecting the area between the windshield and the hood. It does this by making sure no unwanted elements get into the windshield wiper system or the cabin filter area.

• Rules shown image have to be followed while designing the drip area

6.A-Pillar Mounting

• The forward-most roof pillar, forming the uprights that support the windscreen. The pillars are named alphabetically by order of placement from front to back of the car.
• The fender has the mounting at the bottom of the A-pillar.

7.Sill Mounting

• Sill Mounting is present at the rear bottom of the fender where the BIW bottom portion is present.
• The below Image shows the sill mounting.

8.Bumper Mounting

• The bumper is the frontmost part of the car.
• Bumper mounting is present near the front of the fender.

9.Manufacturing Process used to make fender

• Majorly all sheet metal components are designed by using a deep drawing process. The below content explains about deep drawing process.
  
• The illustration depicts the deep drawing technique. A punch, die, and binder is stiff tools.
  After inserting the metal sheet blank, the plate holder shuts in deep drawing.
• The sheet is then clamped between the die and binder. This procedure slows the flow of the sheet as it is pulled,
  preventing wrinkles from accumulating under the binder. The punch creates the sheet in the die by stretching it over the die radius.
  As a result, the amount of punch power required for formation is gradually increased up to the punch's lower dead center.
  

• Trimming is the removal of excess metal from a stamped part to allow the part to reach the finished stage or to prepare it for subsequent operations.
• The below image shows how trimming works.

• Bending is a forming operation in which sheet metal is subjected to bending stress thereby a flat straight sheet is made into a curved sheet. The sheet gets plastically deformed without a change in thickness. Die and punch are used for bending.
• The below image shows how bending works

• Piercing is a shearing process in which raw metal is pierced with a machining tool, resulting in the creation of circular or other shaped holes.
• The below image explains how piercing works.

FENDER DESIGN :

1.AIM - Design of front fender of a car

2.OBJECTIVES

• To create mounting for the Drip area
• To create mounting for A-pillar
• To create mounting for Sill
• To create mountings for Bumper
• To create mountings for Baffles

3.MASTER SECTION TO CREATE DRIP AREA :

PROCEDURE TO CREATE DRIP AREA :

• While designing the drip area, a 150mm clearance is maintained from the front-end for headlight fittings and 200mm clearance from the rear-end for the wiper motor assembly (Cowl top area)
• The depth of the drip area is maintained at less than 60mm so as to avoid the spring-back effect.
• Ribs are provided at the fender drip area to increase strength in that area.

STEP 1 : Use law extension from the given flanges of the fender following the master section.

STEP 2 : Give face blends to all the law extended flanges.

STEP 3 : Sketch the mounting area face and holes of 5 mm dia, holes should have 10mm dia flat surface.

STEP 4 : Project the sketch on the drip area surface.

STEP 5 : Create a datum plane to give emboss to that respect.

STEP 6 : Give emboss of 3.0mm.

STEP 7 : Trim sheet for holes.

STEP 8 : Give face blends to emboss.

STEP 9 : Create Dart in the middle of three emboss.

STEP 10 : Give edge fillet and make sure there are no any sharp edges and should have smooth transition of surfaces.

PROCEDURE TO CREATE SILL AREA MOUNTING :

STEP 1 : Extend the sheet of the fender from its edge of the sill area.

STEP 2 : Create a datum plane with respect to the extended surface.

STEP 3 : Sketch the mounting area face and holes of 5 mm dia, holes should have 10mm dia flat surface.

STEP 4 : Give an emboss of 5mm with an end cap as the plane we created earlier.

STEP 5 : Trim sheet for holes.

STEP 6 : Give face blends to emboss.

STEP 7 : Sketch relief area on both sides of the sill mounting area if needed.

STEP 8 : Trim the sheet for the relief area.

STEP 9 : Bridge curve on sheet to remove sharp edges.

STEP 10 : Trim the sheet with bridge curves making sure that there are no any sharp edges and should have smooth transition of surfaces.

PROCEDURE TO CREATE BUMPER AREA MOUNTING :

STEP 1 : Use law extension to the 90 degrees of the face and 28 mm length.

STEP 2 : Bridge the curve to the both corners of the extended sheet.

STEP 3 : Trim the sheet to avoid sharp corners.

STEP 4 : Create a dart in the middle of the extended sheet and fender flange.

STEP 5 : Give an edge blend of 3mm.

STEP 6 : Create a datum plane with respect to the extended surface.

STEP 7 : Sketch the mounting area face and holes of 5 mm dia, holes should have 10mm dia flat surface.

STEP 8 : Give an emboss of 4.0mm with an end cap as the plane we created earlier.

STEP 9 : Trim sheet for holes.

STEP 10 : Give face blends to emboss making sure that there are no any sharp edges and should have smooth transition of surfaces.

PROCEDURE TO CREATE A PILLAR AREA MOUNTING :

STEP 1 : Bridge the curve to the both corners of the extended sheet.

STEP 2 : Trim the sheet to avoid sharp corners.

STEP 3 : Create a datum plane with respect to the extended surface in offset of a few millimeters above the surface and select the sketch orientation.

STEP 4 : Sketch the mounting area face and holes of 5 mm dia, holes should have 10mm dia flat surface.

STEP 5 : Project the sketch on the A pillar area surface.

STEP 6 : Create another datum plane with respect to the extended surface.

STEP 7 : Give an emboss with an end cap as the plane we created earlier.

STEP 8 : Trim sheet for holes.

STEP 9 : Give face blends to emboss making sure that there are no any sharp edges and should have smooth transition of surfaces.

PROCEDURE TO CREATE SPLASH / BAFFLE AREA MOUNTING :

STEP 1 : Offsetting the curve of face blend edge to 5mm below.

STEP 2 : Creating bridge curve from offsetted curve to edge of the fender to show smooth transition of surface after trim at three portions of fender to create baffle mounting.

STEP 3 : Trimming the surfaces as shown in the picture below.

STEP 4 : Create a plane few millimeter above the surface of the the fender

STEP 5 : Sketch the two circles of 5mm dia, holes should have a 10mm dia flat surface and have a large distance between them.

STEP 6 : Project the sketch to the surface.

STEP 7 : Trim the sheet to show the holes on the baffle area.

STEP 8 : Do the same for the rest of two baffle areas as shown in the picture below.

STEP 9 : Thicken the Fender Part

CREATING SIDE LIGHT SLOT :

STEP 1 : Sketch an ellipse on the YZ plane.

STEP 2 : Project the sketch on the body of the fender along vector X direction.

STEP 3 : Trim the fender with an ellipse curve along vector X direction.

STEP 4 : Use law extension definition and extend the ellipse edge by a few millimeters along vector X direction.

STEP 5 : Use face blend to remove the sharp edge.

NOTE : Have to create holes for side light mounting on fender.

Conclusion :

Designing Front Fender with the necessary mountings are done as per the Master section with the design parameter an final model is shown :