Composites

This week assignment is to make 3D mold and produce a fiber composite part in it.

What is the composites

A Composite material is a material made from two or more constituent materials with significantly different physical or chemical properties that, when combined, produce a material with characteristics different from the individual components.

Machines I will use

Soft-wares I will use

Tools I will use

Designing Time

For making the design I will use Fusion-360 For making the design. I decide to make a design of a plate this image show the design.

Steps for making the design

At first I draw an ellipse withe dimension (80 mm x 250 mm)

After drawing the ellipse I make extrude for 4mm

Then I draw line and split the ellipse from half using split body tool

The final step is that I make cube with dimensions more than the ellipse and make combine between the cube and the ellipse so I have the design as in the following image.

After I make the design I decide to mill it using shopbot machine so I will export the file in stl format.

<a href="https://sketchfab.com/models/eff0167608a2454db234290f52d9bd1b?utm_medium=embed&utm_source=website&utm_campain=share-popup" target="_blank" style="font-weight: bold; color: #1CAAD9;">Compo V1</a>
by <a href="https://sketchfab.com/ahmedhadhoud?utm_medium=embed&utm_source=website&utm_campain=share-popup" target="_blank" style="font-weight: bold; color: #1CAAD9;">ahmedhadhoud</a>
on <a href="https://sketchfab.com?utm_medium=embed&utm_source=website&utm_campain=share-popup" target="_blank" style="font-weight: bold; color: #1CAAD9;">Sketchfab</a>

Now after I have the stl file I will import the file to the vcarve pro software. This is image of the file in vcarve pro software

I will start generating the tool paths, for this design I will generate two toolpaths.
First tool-path is roughing, for making toolpath I will use 1/2" Two Flute Straight V Flute This image show the specification of the bit

Second tool path is finishing the mold and for it I will use Ball Nose milling bit This image show the specifications of the Ball Nose

shopbot time

for starting using shopbot I will prepare every thing like - Fixing the foam.

This image show the mold after the machine finish

This image of the final mold after I make sanding for it using gloves

Then I cut the mold to be ready for the next step

making the design of the jute fabrics.

For making the design of the jute fabrics I will use CORLEDRAW software to make the design at first I take the measurement of the mold which is 25cm * 27 cm.
I know this measurement from Fusion-360 software

This image of the design.

For cutting the jute fabrication after many tries this the setting of the machine.
Then I started cutting the jute fabrics with Universal 40W CO2 laser cutter. The settings were 100% power, 35% speed, 500 PPI, and 0.6 mm Z-Axis.

after I finish it I will cut it using the laser cutting machine twice time with two different angles.

making the composite

First I prepare all materials as in this image

We source the resin locally the product name is D.E.R.331 and this is the link of Datasheet of the resin. This resin consist of two material A which is the hardener one that come in container of 1KG and the epoxy resin (material B) came with container of 5 KG .
For calculating the volume of the resins (A & B) by calculating the volume of the resins I need 202 cm cubic of the resins. As the ratio between the two resins is 1 to 5 so I will use 33.5 cm cubic of resin A and 168.75 cm cubic of resin B.

Before mixing the material I should read the material safety datasheet to know the safety I should have before start mixing this is the link material safety datasheet
So after I raed the material safety datasheet I should wear coat, gloves and face mask during the composite.

After I put the two resin I start flipping the two resin. This is the image of the resin after I finish

The next step is to put the jute fabrics in the resin and be sure it completely in the resin and squeeze it will as in this image

Then I put it on the mold as in this image

After I finish the two jute fabrics this the image of final thing

Now I will but it in the vacuum bag as in this image

and get all air inside the bag out using vacuum cleaner After I finish I will leave it over the night This is the image of the final composite

This video show the final thing I have

Conclusion

We are new fablab and we are rushing for doing fab academy so we didn't have the Perforated Film and Breather Material but we will buy it on the future and I will try it.

Design files