Fab Academy

Miguel Lourenco
 


 
 
 

  
 
 
Molding and Casting

This week I decided to make a ISP case, modeling and casting two parts.

 

Begun to draw a rough CAD model of the ISP, after that drawn the upper side of the box and lower case with rough model (ISP) reference.

Through digital modeling we can do some tests to detect possible interferences between the two halves. If there is no interference, we can to obtain the relative molds for each part.

I added fillets to aid the demolding operation.
 

The molds will be cut in CNC milling (Roland MDX-20), using a small endmill for roughing cut and ball end mill for finishing.
 

 
 

Box with ISP inside - Digital model

Rough CAD model of the ISP

 

Mold (STL) relative to upper half case and to lower half case

Definig cut parametres with Artcam (delcam)

Milling tests with Plaster blocks

 

 

Fab Modules (cutting paths)

Wax molds after machining operations (rear)

 

OOMOO 25

 

CAD and Castting Silicone

 

Flexible molds (silicone-oomoo 25)

Casting part (resin with black powder aniline)

Casting part (resin with black powder aniline)

Casting and molding aplication.

 

 

 

 

These are the molds for upper side box and bottom side box of ISP. they can be immediately saved as STL files.

 

To saving time and tools, made two cutting paths.

First one for rhough cutting and seconde for finishing action. Used two diferent milling tools.

 

 

 

Finally I tried milling the molds using plaster solid blocks.

 

 

 

Finally we have wax and casting stuffs.

 

Now, I choose to molding and casting car wheel caps (fab logo).

 

For a tridimensional part I need two molds.

Again, I made two cutting paths.First one for rhough cutting and seconde for finishing action. Used two diferent milling tools.

 

Now I used Fab Modules and Modela to perform the necessary cutting operations.

 

Wax machining with Modela

 

 

 

 

Used silicone liquid rubber (two components in porportions 50%+50%)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The four guide pins and holes must be greater than the picture shows, because I had some problems to align the two silicone molds together.

The central hole is for insert the resin and the two other holes are for air goes out.

 

 

 

 

 

 

 

I mixed black aniline to the resine to obtain a color part.

 

 

 

 

 

 

 

 

 

 

 

 

Finally, I painted the casting part and applied it to the wheel.