Composites

Read the material safety data sheet (MSDS) and technical data sheet (TDS) for the resins that you're using.
Design and fabricate a 3D mold (~ft2) and produce a fiber composite part in it.

Designing and making a 3D mold

This week I focused on designing the top cover for my game’s unit. See the design of the unit on the fifth week assignment, 3D Scanning and Printing.

Designing in layers

I started with designing both male and female molds for the molds. Next I separated the models into different layers. Layers for 3D and layers for 2D milling in order to save milling time of the machine. The thickness of the layer set to 27.2mm according to the material thickness, I used MDF.

2D layout file:

download ai.file download DXF.file

3D model:

download 3dm.file

3D parts:

download folder
Milling process

I’ve imported 3D files into ALFACAM as IGS and 2D files as DXF.

  • For the 3D milling I used a 10.27mm Ball nose, double flute upcut milling bit.
  • For the 2D a 6.35mm flat, double flute upcut milling bit.
Preparing the molds
  1. Glueing and clamping together the layers.
  2. Sanding the molds.
  3. Sealing the mold with epoxy.

Assembling the composites

My first try was with the female mold.

The layers of the composites

I cut the fabrics according to the mold layout.
The layout that the software produce wasn’t suitable for the fabrics. I had to changed the sharpen edges to one segment.

These are the layers:

  1. Five layers of a fiberglass, each other layer with a 45 angle of the fibers direction.
  2. Two layers of a peel ply material
  3. One layer of a bleeder material
Assembling

I spread the mold surface with Honey wax then laid the layer one on top of the other surfaced outside of the mold, thinking that laying them outside would be easier to place the layers inside the mold.
After finishing placing I filled the mold with a nylon bag and sand. This try didn’t succeed.


For the second try I used the male mold and repeated the preparation process of cutting the layers. This time I tried to assembled the layers on top of the mold and to placed it inside of a vacuum bag.

The materials i've been using