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Read the material safety data sheet (MSDS) and technical data sheet (TDS) for the resins that you're using
Design and make a 3D mould (~ft2 /30x30cm), and produce a fibre composite part in it



Material safety data sheet (MSDS)

Carbon fiber
Silicone Ruber
Polyester resin .

Technical data sheet (TDS)


Carbon fiber
Silicone Ruber
Polyester resin .




Learning outcomes:
1)Demonstrate workflows used in mould design and construction



To work with in this assignment is necessary use personal protection in your hands with gloves, the nose with gas mask and your eyes with glasses.

Is really important take in account this recommendations to your personal protection, we use protection in hands because we are going to use chemical materials, we use mask because this composites emit toxic gas, also we use protection with glasses becase the toxic gas can affect our eyes.



In this assignment I decided to use my mould than I created on the class of moulding and casting.



The first step was applying release agent, you can use oil, I used a typical oil to cook. I applyed the oil in the mold before to apply the composite material.
You have to apply the oil on the mold to prevent join the materials. see the next pictures,you have to apply the oil or a different material to prevent the join of materials.




2)Select and apply suitable materials and processes to create a composite part.



When the mold is ready, we have to prepare the composite material, I learned about it with Guillermo Guerra because he knows about this theme. he recommends me use Polyester resin with carbon fiber, he said me than it is a great idea to make the composite on mi mold. I was learning and we made a test with to materials, in the first picture. we used the carbon fiber and Yute. In the next pictures are my mold with the polyester resin.
To apply the resin you have to use protection on your hands.
also you have to use Scotch or tape on the polyester resin to hold the edge of the material, because it is like a lot of wires and we have to hold together these.



I applied polyester resin on my mold, then I applied the carbon fiber and I press the fiber with the mold. to get the shape of my mold with the carbon fiber, then I removed the mold and applied more polyester resin to cover the carbon fiber.
When it is ready press again with the mold, I used a presser to get the shape. then you have to wait around a day to dry .


It is my result, I love it because is really strong, I feel so happy with the result.








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Design and make a 3D mould (~ft2 /30x30cm), and produce a fibre composite part in it



In this assignment I have to assemble a CNC Machine to do my mold, I applied the experience of my assignment of machine design, mechanical design. I decide to add all this experience and information in this assignment.




If you want to review the process to assembly and electronics control.Here



Mold 3D design.

I designed my mold on SolidWorks, I created a shape and extrude the material.
The idea with this shape is have different texture with curves.
I have two molds, positive and negative, you cam see it in the pistures.
Then I export .stl files






When the stl files are ready, we have to create a g code, I am using ArtCam to make it.
If you want to create a g code, open ArtCam and create a new model and configure the size.


Then you have to import the stl file. you have to select the tool "reliefs", then import 3d model and paste.


In the toolpaths tool you can configure the process than you need, I selected relief, because I am using flex foam, and this material is soft.
Then you have to configure the parameter.
Machine safe Z = 5mm
Tool=6mm
Step over=6
Step down=6
Also I was playing with:
Feed rate=50
Plunge rate=25
With this configuration, the material behaving very well. also you can change this two last, it depend of the material.
Material=50
Finally press now to apply the changes.


When the changes is applied you can see red lines, then you can save the file, I was testing some formats and the best to the machine is Axyz.nc


When the file is ready, we can open the CNC control software, and open the file. I am using the bCNC to control the machine.
Then we have to calibrate the 3 axis, and run the software.


The machine has problems with some screws, but I fixed the problem and the time to finish the file was 1:15 min approximate each mold.





Jute and polyester resin

1 Polyester resin
30% peroxide (transparent)
10% cobalt (accelerated purple)

Material safety data sheet (MSDS)


Polystyrene.
Polyester resin .
Peroxide MEK.
Cobalt.

Technical data sheet (TDS)


Polystyrene.
Polyester resin .
Peroxide MEK.
Cobalt.

Before to use chemical composites, the principal recommendations is use the correct protection, mask, gloves and safety glasses. also i recomend to work in a open place, because if you are working in a closed place, the gas generated by the composite can afect your healt.

We have to use protection with a mask and Protection glasses; it is necessary find protection like this for example.





Using a sheath plastic, cover the mold and put the jute up on the sheath plastic.
Prepare the recine with the percent.
Take care to use this composites, see the next file to learn the kind of precautions to apply.
I am using syringes to measure the composites.
Testing.


It was an extremely interesting mix the components, but when I was mixing I exceed the percent of peroxide and the mix expanded, and you can see in the picture. I think than it was a new experience to me, in the firt experimentation with composites using resin with carbon fiver, I do not had problem, but now with this resing I learned than the composites has diferents and really crazy reactions. also I damage my mold because the resine was so hot.




I think than the best way to work with this kind of composites, if you are learning for the forst time, you have to take help with some one who knows about it. also i think than when you are going to mesure the material you have to write and take care to do not mix, that is the most important in the mix, the porcent can change the reaction of composite, and it can be dangerous, in my case it was not really bad.


I fixed the problem with the mix and y apply again the resin on the mold.
We was looking urethane to mechanize the molds but we did not find it, I know than poliestireno do not like to Neil, but we was seting the velociti to avoid gases harmful to health, also we are using masks for caution.
I put the first mold, over it a plastic sleeve, then I put thejute, over it another plastic sleeve and finaly the second mold. over all I press the mold with a box to apply weight.



Hero foto



Video





Included your design files.
STL files molds and SolidWorks files
ArtCam files (.nc)

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