Assignment
* 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 and produce a fiber composite part in it.
Neil's class Summary
Design
For the task this week I decided to create a small object, I was thinking that perhaps it is time to make a case for the pinhole camera that I made for the computer-controlled cutting assignment of the third week.
I made a sketch of the idea: it will have two parts that can be separated to place the camera and will be closed thanks to small magnets inserted in the sides.
I digitalized the design using Autocad.
Fabrication
For the task of this week I want to work based on a material composed of burlap and resin polyester. I did a first test using 4 and 6 layers of burlap in a very simple mold of machinable foam.
I waited 24 hours before demolding and still the results were not good. The foam zones in contact with the resin melted and for some reason the resin did not catalyze at all. The result was a very flexible material and not rigid.
I decided not to work with the foam as mold material. I could not find any piece of wood or other material with good characteristics for the mold and the desired thickness for the height of the case.
So i finally decided to make the mold based on glued up stack of 5 mm laser cutted wood pieces. (Both CNC and lasercut files in download link below)
I also used the laser cutting machine to give more specific shape to the burlap pieces.
I placed vaseline in the molds and counter molds, applied 4 layers of burlap + DCPD unsaturated polyester resin with the corresponding catalyst: Mek Peroxide (20 to 25 drops of catalyst for 100gr of resin) and then compressed the molds with clamps for about 12hrs until demold.
Here is a video of the complete process.
And here is the result.
Download the files.