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

week 10 challenge:

feature attachment: ribs and screw boss.

AIM:

To create a door handle plastic component through a given class a surface and also create a ribs and screw boss on it.

software used:

catia v5 R20

procedure:

download the given class A surface, then open it on the catia v5.

CLASS A SURFACE:

using join command join the given class a surfaces into a single surface.

using a boundary command in surface workbench, check whether it is joined properly or not.if not try to fix it.

here is shows the class A surface.

TOOLING AXIS:

creation of tooling axis . check for the plane which should be easy to  create using injecton moulding and choose a hole slot or a plane surface .

then create a point in it and a dummy tooling axis. then, check for a parallel and slope surface. using a intersect command draw a intersecting line of x and y separately.

then draw a tooling axis for x and y separetely using a bisecting line . then draw a tooling axis as shown below.

DRAFT ANALYSIS:

for draft analysis, in surface workbench click on insert>analysis>feature draft analysis as shown below:

now click on compass to create c compass and place it on the tooling axis.

click on the class A surface to check the draft in the surface.

from the below figure it shows green which means it has a draft of more than three angle.

because less than three degree angle was difficult to manufacture.

 if the draft angle is less than three degree change the tooling axis angle or position and try it.

in this the degree of it is 2.7 something where it cant be cleared.

 SURFACE B :

for creating a class b surface. first extract a plane surface and then untrim it. now extrapolate the untrim portion . then trim to get a final output. and offset it to a thickness of the component.

for this challenge, it is directly offset to the thickness of 3mm.

here only one patch is missing. it is filled using a fill tool to obtain a class b surface then it is extrapolated.

here it shows the CLASS B SURFACE.

note:

to check the clas B surface.create a boundary on it . if the booundary was along the corner it is perfect if not check it.

CLASS C surface:

creating a class c surface firstly create a boundary along the class a surface. then using a sweep command sweep it.

for this boundary two individual boundary are created and then join together.

after creating a boundary, sweep  it with draft direction as shown below for the surface which is perpendicular to the tooling axis..

for surface parallel to tooling axis it is sweep with the referance surface.

after sweep it is extruded and trim to obtain a joined surface.

after creating a class c surface. using a trim command join the CLASS A and CLASS C surface to get a joined surface as shown below.

FINAL OUTPUT:

then trim the joined surface of A and C to the the classB surface to get a final output as shown below:

note:

create a boundary in the final trim. if it shows no boundary. then it is a closed surface.

else it has some open surface. patch it or fill the opens.

now, from the part design. create a solid body

FEATURE ATTACHMENT:

for ribs:

create a positioned sketch and draw a line on the surface of the trim body.

insert a part body and do the following.

then using thick surface thicken the line with 0.4*thickness of the component.

: 0.4*3=1.2mm.

the height of the ribs are 5*thickness of the component.

: 5*3=15mm

draft angle is .5degree per side.

radius fillet of 0.125*thickness of the component

:0.125*3=0.375mm

after creating the single rib, for second rib do the same with a gap.

and finally union trim the part body and the rib body together to obtain the rib:

the meron color shows the ribs.

for screw boss design:

this are the design rules followed for the screw boss design.

here, the diameter D is 5.2mm for M6 thread.

then the outside dia is 2D, 2*5.2=10.4mm

height of screw boss was 3T=3*3=9mm

draft angle of 0.5 degree.

depth for bottom was .3*thickness

:0.3*3=.9mm

now assemble it with the part body to get the final output.

here the brown color shows the plastic component, cyan color is the screw boss and meroon shows the ribs.

tree structure:

 

ALL views:

 

conclusion:

from the above, Created the door handle Plastic component and ribs and screw bosses through the given Class-A surface. 

the catpart file is attached below.

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