composites
All my ideas this week seemed like they would be hard to do without using the slow, toxic, clear resin. So, I decided I would just experiment with colored fabrics, the fast resin, and lasercutting in hopes that it might be useful for my final project (currently thinking of a more elaborate gazebo).

I had lots of different fabrics at home, which I cut up into simple shapes.


I have few pictures of the next steps because the process was so messy, and I had to work very fast.

I arranged the fabrics in a pleasing pattern on one side, put down some linen scraps in the middle for strength, and then made another pleasing arrangement of colored fabric on the top. The resin hardens pretty fast, so you have to be quick!!!! I decided to just make a sheet of composite rather than wrapping the fabric around a core or using a mold because I wanted to lasercut it after. I contemplated putting cardboard in the middle, but I decided it wasn't needed (and it wasn't). When you seal the vacuum bag, check the edges for leaks! They can be very small and hard to find.


The result actually turned out much better than I expected! I thought that it wouldn't be clear enough and that it would be really brownish, but the colors came out great!

Front:


Back:


I made an .ai file of an abstract snowflake shape to lasercut out of my material.

Lasercutting was tricky. I tried to use the settings for medium thickness acrylic, but it was barely etching the material. Furthermore, my material was thicker in the middle than on the edges, so I had a lot of trouble finding settings that cut through the center. I ended up increasing the power quite a bit, and slowing down the laser to find a setting that actually cut through the material.

Another problem was that each time I checked if the laser cut all the way through, I ended up moving my material a tiny amount because it's not very flat.

Finally, the last setting I used cut all the way through the material, but it was catching fire while it was cutting especially in the thinner areas. Maybe this could be avoided if the material were more even, and if I had used a slightly different setting.


However, the cut out piece looks nice! I cleaned it up with scissors, cutting pliers, and sand paper.

The remaining material also looked cool, so I trimmed the edges (which were thin) with scissors.

One more issue: the flames melted the resin, which is apparently pretty flammable. I picked it up from the lasercutter without gloves, and it was sticky and I got resin on my hands (which is not safe!). I washed it off immediately and used gloves to handle it from then on, hoping it would harden again after awhile.


I think next time, I would use fewer layers of fabric and pay more attention to keeping the thickness very even. I think then it would be easier to lasercut or to just use scissors to cut it into shapes.

The resin did eventually harden again, and it all seems fine.


I also got to talk to Kenny, and he said the flames are normal when lasercutting, even with acrylic. He believes if I had waited longer before lasercutting (I waited about 12 hours) or done a post-cure in an oven, melting would have been less of an issue.