Fender Design

FENDER

Fender is the US English term for the part of an automobile (vehicle body) that frames a wheel well (the fender underside). Its primary purpose is to prevent sand, mud, rocks, liquids, and other road spray from being thrown into the air by the rotating tire. When the vehicle is moving, tires pick up stones and others and hurl them in all directions, Fenders are present to prevent any injuries to pedestrians and contain the motion of these particles.

This fender plays a major role in pedestrian safety while a car is in motion. When it is in motion the wheel carries over the small stones, and mud particles and throws them away which may harm pedestrians. So while designing these considerations are to be taken into account.

A car body has two types of fenders: front fenders and rear fenders as shown.

Fender can be of two types: full and half bumper types. Nowadays, a half-bumper type fender is typically used. the cost of sheet metal blank is reduced as we can produce two half bumper type fenders in a single blank. This also leads to a reduction of scrap.

    

Design Features of Fender:

                                     

Mounting Area

1. Bumper
2. Drip
3. A-Pillar
4. Sill
5. Baffle 

BUMPER:

The bumper mounting area is used to fix the plastic bumper to the fender with the help of the fasteners

DRIP:

• It is the important mounting unit of the fender. it is connected to the engine compartment, therefore a lot of design constraints are to be followed while designing the Fender 
• While designing the drip area we have to leave 200-300mm for the cowl top initially
• For placing the headlamp we have to leave at least 150mm at the front while designing the fender 
• The cowl top part consists of a wiper motor and its instruments

A-PILLAR AREA

The A-pillar is the structural pillar that combines the body with the roof. this makes the sides of the windshield rest. front fenders are fastened to the A-Pillar to form a robust structure.

SILL:

The sill is the panel directly below the bottom of the door supporting the floor and may be used to combine the floor and the body. The bottom end of the fender is mounted on the sill body for reinforcement of the fender panel, thus the sill mounting position is designed with holes and emboss. M5 fasteners are used to fix the fenders on the sill body.

BUFFLE

Baffle mounting or mudguard are clip-fit mounting types on the fender arch's inner side over the tire. it protects the car engine component and pedestrians from causing injuries from chip-out debris on the road when the car is in motion. they are mounted on the fender using a special type of plastic locking clip.

Manufacturing process

The manufacturing of the Fender majorly involves these operations.

1. Embossing
2. Bending
3. Cutting and Blanking

OBJECTIVE:- To develop the front fender using Nx cad following the design parameters.

Given Master Section 

 Given Surface(input skin):-

   

Drip area Design

Drip area mounting is an important part of the fender. This mounting is attached to the engine components of the car. The fender drip area is mounted via weldnuts to the engine comportment. 

• The height of drip area mounting should be less than 40mm so that it reduces the spring-back effect during manufacturing and reduces NVH issues during vehicle movement.
• It should be distanced at least 150mm from the front side and 250mm from the rear side.
• Mounting screw holes of diameter 5mm and locator pin holes are created for mounting guidance.
• Ribs are to be provided to increase the strength of the mounting part.
• Embosses are created as per design standards for proper fixation.

Sill mounting area design:

Sill area mounting is also an important mounting part. This mounting part is basically on the bottom of the fender. The mounting part should be created such that the fender is firmly attached to the sill to avoid NVH issues. 

Bumper mounting area design:

This is designed by consulting the bumper design team to design the bumper and fender assembly fixation.

A-pillar area mounting design:

The A-pillar area mounting depends upon the A-pillar of the car.

Design of Baffle Mounting area:

A baffle mounting area or mudguard are clip fit type of mounting on the inner side of the fender arch over the tire. It protects the car engine compartment and pedestrians from causing injuries from chip-out debris on the road when the car is in motion. they are mounted on the fender using a special type of locking clips which are made up of plastics.

RESULT:

A thickness of 0.75mm is given to the surface to produce a solid body 

Commands used from NX CAD to model this design are:

1. Offset in face 
2. Curve on surface
3. Trim sheet 
4. Law extension 
5. Datum plane
6. Intersection curves
7. Face blend 
8. Bridge curve
9. Sketch
10. Projected curve
11. Emboss
12. Edge blend 
13. sew
14. Dart 
15. Thicken

Conclusion:

Thus, all mounting areas for the fender designed from skin data and the master section are done by following all design rules.