Challenge

Fender Design

SShubham Kumar12 Jun 2023

Objective : To design a Fender mounting on the given model by using Master sketch by considering the safety and manufacturing feasibility for possible mounting region.

Design the drip area according to the given master section and also sill, Bumper, Baffle and A-Pillar mountings.

Introduction :

Fender is the US English term for the part of an automobile that frames a wheel well. 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 basically present to prevent any injuries to pedestrians and contain the motion of these particles. Most passenger automobiles have four fenders, one over each wheel. For vehicles with a narrow car body that exposes the tire, the fender is an exposed curve over the top of the tire. For wide body vehicles that cover the tire, the fender forms the wheel well surrounding the tire, and is not directly visible from above the car body.

More elaborate designs include fender skins for enclosing the outside edge of the wheel well, and stylized pontoon fenders for exposed fenders.

Sticky materials, such as mud, may adhere to the smooth outer tire surface, while smooth loose objects, such as stones, can become temporarily embedded in the tread grooves as the tire rolls over the ground. These materials can be ejected from the surface of the tire at high velocity as the tire imparts kinetic energy to the attached objects. For a vehicle moving forward, the top of the tire is rotating upward and forward, and can throw objects into the air at other vehicles or pedestrians in front of the vehicle.

Need of Fender:

It is designed to provide resistance against wind, muds, and roadside particles.
It is the sheet of metal covering of the car.
Fender has a plastic part called Baffle or fender Liner which fits underside the fender to protect the metal from corrosion by stopping the flow of mud and water inside from different road conditions.

There are 2 types of fenders:

Full Bumper Type
Half Bumper Type

Full Bumper Type : The full bumper type model is used in the older days this creates much wastage of material and the unnecessary cost is increased.

Half Bumper Type : This half bumper type is used for mainly cost and material cutting purpose as this type is also provides ease of manufacturing and the strength is also improved for half bumper type fender.

Design parameters:

Drip area mounting is the important part in the fender. This mounting is attached to the engine compartment of the car. Fender drip area is mounted via weld nuts to the engine compartment. A minimum of 150mm distance is kept from the front side and a distance 300mm or less can be kept on the rear side. The total length of drip area from the top of fender should be less than 40mm. This is to avoid the spring back during the manufacturing. The edge of the mounting should at least 10mm away from any nearby component in the engine. A rigidity bead is provided at the end to increase the strength of the mounting.

The front fender is manufactured as a separate part, this is then mounted to the body of car for this the front fender basically has 5 mounting points can differ from one OEM to another OEM.

The following is the important areas:

A-Pillar Area: The A-pillar area mounting depends upon the A-pillar of the car. The mounting can also be provided with ribs to strengthen the part. This mounting is critical in design as it has to be mounted on A-pillar properly.

Body Side Area: Another mounting point is created for the body side on the fender. This mounting is created such that it can be mounted on the body of the car. It may consist of one or two bolting holes.

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

Cowl Area: Sometimes fender is also provided with the cowl area mounting. This mounting is on the top side of the fender. It is used to attach the extruded rubber sheet material over the wheels.

Design Procedure:

The skin data from given file is we need to open first in the NX cad software and in that we need to create the some mounting area for the fender. So for the fender mounting is has the different types usually it’s vary for OEM to another OEM. So here we are going to create the Drip area, A-Pillar, sill area, Bumper mountings and Baffle mountings area on the given part.

Design parameter for Drip area mount: