Design of backdoor

Aim: To create a backdoor assembly with the help of a given class A surface.

Procedure:

1. Surface Preparation
   1. First we will try to check the distance between surfaces by using distance propagation which is in the join command.
   2. If all surfaces are not selected, then there are gaps between surfaces.
   3. In our case, all fillets o surfaces have some gaps, so we will extract all the surfaces except fillets.
   4. After this we will use the blend command or bitangent fillet in the surface fillet command to give all the fillets and then join all the surfaces.
   5. We will try to rebuild the surface with sharp bends by using a multisection surface and joining them.
   6. For the surface like the lower outer panel, we will use rough offset to get the offset of the surface and then offset the rough surface back to its original surface and split the surface using the boundary of the original surface.
   7. Now we will make a flange for the lower surface so that I can be spot welded with the upper surface.
2. Inner Panel:
   1. Unlike the outer panel, the inner panel will be a single product.
   2. First we will make a working surface by offsetting the class-A surface which we made earlier that will be used as a reference.
   3. Sealing flange
      1. Now we will create a split of the surface which will be the part of the sealing flange which will push against the rubber seal on the car frame.
      2. To make this flange we will offset the flat surfaces which we need as the reference of placement and then we will trim a strip of 30mm surface all around the door.

• We will join the gaps by multisection surface and we will join all surfaces together.

1. As the surface is perpendicular to the tooling axis, we can use a reference surface for sweeping the surface.
2. We will use the surface fillet command to join and give a fillet of 4mm to both flange and the working surface.

1. Inner panel surface
   1. To create the inner panel surface, first, we will take the frame for the window and we will trim it with a sealing flange.
   2. Now we will create a multisection surface to create the lower part of the inner panel and join it together which will give us the basic inner panel.
2. Hinge, gas stay, and viper motor embosses
   1. for every embosses we will take the nearest curve and use the normal to curve command to create a plane where we will create a line that will give us the flat surface to create our emboss.
   2. We will use this line to create a sweep in both directions to create a flat surface.

• Now will use this surface to create a sweep and trim it with the inner panel surface.

1. Join all surfaces and give fillet to all sharp edges.

1. Structural emboss
   1. To create structural emboss, we will first create a sketch on a plane parallel to the inner panel and create our own emboss design which will resist the flex in the panel.
   2. Now we will project this sketch on the surface and then split it.

• Now we will create the sweep inside these cut-outs regarding the tooling direction.

1. Now we will offset the inner panel and trim it with the sweep we created to create the emboss.
2. Give fillet to all sharp edges.

1. Mastic emboss
   6. To create this emboss we will create an offset of class A by 6.5mm.
   7. Now we will create a square cut-out and we will create a sweep only on one side of the cut-out.

• We will trim the offset surface with the sweep to create an emboss.

1. Now we will give all the fillets and then measure the length of the cut-out and offset the curve on the flange and trim it.

1. After creating the mastic emboss, we will mirror the surface.
2. Striker emboss.
   1. For striker emboss, the striker should be perpendicular to the trajectory of the striker which will ensure perfect locking lock and striker.
   2. To ensure that we will make a trajectory by using a latch emboss hole’s center axis for both sides and draw a circle on a plane perpendicular to the inner panel surface.

• Now we will create a line tangent to the circle and then draw a line perpendicular to that tangent line which will be our base for embossing.

1. Make sure the line for embossing will be close to the bottom side of the inner panel.
2. Now we will create an emboss in similar steps as we did for embossed other embosses.

1. Now our inner panel is complete and we will thicken it from the inside (between inner and outer panel) by 0.75 mm.

3. Reinforcement
   1. We will create reinforcements for the hinge, gas stay, viper motor, and striker embosses in between the inner panel and outer panel.
   2. We will start by extracting the surfaces of inner embosses and surfaces around them.
   3. We will join and trim the surface to the required dimension.
   4. Now we will thicken this surface to 1.5 mm.
   5. We are taking 1.5mm because we are going to use a waste sheet from other parts of the frame.
   6. We will spot-weld all the reinforcement to the inner panel.
4. Hemming process
   2. For hemming, we will first offset the class A surface by 2.65mm.
   3. We will use boundary to take the outside boundary of the surface and offset that curve on the surface by 10mm using a parallel curve and split it.
   4. We will use sweep with a reference surface and we will use class A as the surface.
   5. Now we will use the tangent fillet in the surface fillet option to create the hemming bend.
   6. We will do the same for the outer lower panel too.
   7. Now we will mirror the surface and join them together.
   8. We have completed the panel and assembly after thickening both outer panels by 0.75mm.