Week 10 - Challenge 1- Attachment Feature Creation (Ribs & Screw Boss)

Respected Sir,

As per the given rules, the component has made and report on draft analysis is done according to the best of my knowledge. For more information, please look into the below attachment.

REPORT WRITING ON DOOR HANDLE, BASED ON DRAFT ANALYSIS

Initially, the given surface model is seen in 3 different directions such as x, y, and z axis, using compass. This is done to select appropriate axes which cover the entire surface of door handle. Thus, an appropriate axis is selected to create draft analysis. Before doing drafting analysis, the important thing is to create a dummy tooling axis to find the main tooling axis. In simpler surface models, we selected the flat surfaces or flat surfaces consisting holes in a rectangular planes to create the main tooling axis. As we know that, door handle is a type of complicated unique shape. Hence, entire surface model is selected directly to do the drafting analysis by creating the dummy tooling axis as the main tooling axis.

Fig (a) representing the point selection on curve, by setting the compass in y direction, as y axes covers the entire surface, on which we can create dummy tooling axes with the help of point ‘on surface’ option. Also Fig (b) is mentioned below, where line is created as tooling axes.

By using intersection command, an appropriate plane and class A surface is selected. Now the sketch is generated, through which draft lines has to be selected. Here it is observed that, there are no draft lines in the sketch, i.e., all the lines in the sketch were normals with zero degree inclination. with the help of line command and point generated on the multi-extracted surface, directly an actual tooling axis have drawn. Now, this tooling axis which is generated will help us to create a class C surface using sweep command in future or further processing.

Similarly, another image is represented above as Fig (b), which depicts the line drawn through the point created using the line command, by selecting point-direction option. This line drawn is nothing but, it acts as a dummy tooling axis. Due to complicated surface model, this dummy tooling axis is referred as main tooling axis and done draft analysis further.

The same tooling axis is used during creation of class C surface. During class C surface some of the sweep models were created by selecting the main tool axis direction. The sweep models made using tooling axis were shown below in the form of figures.

The above 2 figures, Fig (c, d) represents sweep models were tooling axes created for draft analysis is used to represent the direction and the draft angle is given here as 3 degrees.

It was also observed that the parting line of cavity should coincide with the parting surface, to obtain a good quality part model.

At the end boundary of the door handle, it was observed that the sweep model is generated without providing drafts also. i.e., instead of using ‘with draft analysis’ command, I selected the option, ‘with reference surface’, and thus created a parting surface at 90 degrees. Those figures also Iam referring below. Please look into it.

Parting surface perpendicular to the tooling axis

Parting surface perpendicular to the tooling axis

Thus, drafting analysis made on a closed surface after final trim of class- A & C with class B surface. During draft analysis, initially the compass have brought and coincided with main tooling axis. Now, once again the compass option have clicked and moved from the main tooling axis and once again coincided with the same axis. So that the created closed surface is turned into green colour by clicking the mouse pointer on the surface and selecting the inverse draft option. Now, here at 3 degrees, some portion of the closed surface is red, so the value from display which represents 3 degrees is changed to 2.5 degrees. 2.5 degrees is also well suitable for manufacturing the component for some complicated shapes like door handle.

Draft analysis made on closed surface before rib & screw boss design

Draft analysis made on closed surface after rib & screw boss design

It was observed that some of the area is red and blue, which says that draft angle is less than 2.5 degrees, as the area is taken instead of 3 degree draft, 90 degree reference surface, during sweep analysis.

Note: Also I consulted Mr.Aravinth, professional in catia V5, told that some of the class A surface given by them is less than 1 degree. So, where ever the 3 degree draft is required, at essential areas required draft is obtained.

Thanking you.