Week 8 - Challenge 4 - Coin Holder Design

Draft Analysis in Catia

The Draft Analysis command enables you to detect if the part you drafted will be easily removed. This type of analysis is performed based on color ranges identifying zones on the analyzed element where the deviation from the draft direction at any point, corresponds to specified values.

so when we perform a draft analysis over a surface or on a component there will show 3 types of colour code, that is GREEN,RED and BLUE.

these three colours are corrospondes to the angle value present it that area.

If the colour is GREEN then the angle prensent in that are is 3 degree or mor than 3.

If the colour is RED then the surface having 0  to 3  degree andgle to the area.

If the colour is BLUE the the surface having the negative angle on that area.

Thes conditons are shown bellow

 

Creating a tooling axis with Bisecting Method

• Analise the surface so we can find the direction for the tooling axis so in this case it is Z.
• To create a tooling axis with bisecting method firstly create intersection line in X and Y direction.s

    To create to the tooling axis or say tooling direction, extract the base surface of the class A surface and create point at centre of that extracted surface. Insert axis system on that point.

   Now create intersection using position sketch in both X and Y direction.

  Create Bisect line in each X and Y direction sketch using that midpoint.

clearing X dirction 

Clearing Y direction

  Then create a bisect line using X and Y line and name it as Tooling axis.

 

DRAFT ANALYSIS FOR CLASS A SURFACE

To preform the draft analysis over the class A surface, change the view papameteres in to material mode, insert dranft analysis click on compass and align the compass with the tooling axis, lock the compass position and click on the surface to perfom draft analysis. 

As you can see in to the above image wihich i highlighted using sian colour these are has a BLUE colur that mean the angle present on that area is negative, if we design product with this design so it will be fail during the tooling like it will stick over the core part when it will manufacture in the mold, the area on the core side should always have some positive angle so it will easily take out from the mold. and will not stich with the mold.

Solution for that situation is you have to aks the class a surface designer who designed that surafce to give some positive angle to these highligted area. so it will raedy for manufacture.

 

 

   CLASS B SURFACE

To create B surface we have to extract the required surfaces from the class a surface.

Side Walls – to create side walls extract the surface from the class a surface one by one or select the bag icon in the extract option to extract multiple surfaces at once. The extrapolate them well so the surfaces can intersect each other, then trim them to give them a required shape, offset it 2.5mm outside.

Base Surface – Extract the base surface and the sloping surface from the class a surface untrim the surfaces and extrapolate well so it will intersect with each other and with the side walls too. Then trim the both surfaces with each other and offset it by 2.5mm downside.

Top Walls -  Extract the top walls and use multiple extract to extract the top wall because it has a curve surfaces at the corners so it might create problem if we extract it separately so extract it from the class a surface and don’t untrim just use the extrapolate option and extend it upside and downside, offset it inside by 2.5mm.

 

 

Initial Trims – trim these surface side wall, base surface and top wall with each other to get the required shape, trim the base with side walls after that with the top wall as shown bellow.

Side Flange – side flanges we will extract it in phases the outer one first and the inner one second then extrapolated the both side flange surfaces the first extract and the second one with the point continuity. Then trim them with each other as shown, and trim them with the side walls.

FINAL TRIM AND FILLET , FINAL B SURFACE

 

C SURFACE

To crate c surface extract the boundary of the a surface using multiple extract. Then extract the adjacent surface.

Use sweep command use with reference surface command.

select the extracted edges as profile and the surfaces as support.

Give 90 degree angle with the surface, give length so it can intersect with the B surface.

 FINAL SURFACE CREATION 

Join the Class A and Class C surface then trim it with Class B surface. Ensure isn’t have any open boundary using boundary command.

Creating close surface

 go to the part workbench and use close body command to create body inside the final surface and letter on perform draft analysis on the close body.

  Draft Analysis Surface

Switch the view parameters to material mode select the draft analysis command align the compass with the tooling axis, click on the lock symbol to lock the compass position. Then select the component to perform the draft analysis.

Green colour mean there is a draft angle of 3 degree or above than 3 degree.

Red colour mean the angle is between 0 to 3 degree.

Blue colour indicates the angle present in that area is negative.

As you can see the inside of the side walls the surface are blue because we got Class a surface like that, this component can fail when its will send for tooling, so make sure that the class a your taking to design coponent should have the appropriate angle on inside that is CORE side. so it will pass the draft analysis.

 

TREE STRUCTURE