Composites: Artistic Expression

This week we'll be making something from two things: the glue and the fabric. And with this we will make a bowlplate to contain the sustenance of life: food.
I designed it in solid works.

To make sure I can get it out of the compression mold, I made a champfer (sp?).

I made the mold out of foam on the GEAR lab ShopBot. I did two molds, the positive and negative.
Here is my favorite part of ShopBotting, setting the z-height - you attach that clip and then put that plate under your part and it zeroes by approaching the plate til the circuit is complete by just touching. It never even leaves a mark on the plate. Very slick.

Here is my mold after the rough cut and during the fine cut - you can see the difference. The toolpaths for the fine and rough cut were made in Parts Works 3D.

After the fine cut, you can see there's still plenty of roughness (I was using a fairly large drill bit (.25") at a fairly large stepover), so I sanded it down.

Here I am using wax paper to make sure my composite doesn't stick to my mold.

For the fabric, I used fiberglass. We were warned against using it, due to how risky it is to inhale small particles that can do serious damage to your throat; However, I have experience using fiber glass, and more importantly, I did all of the work with it (including cutting the fabric) in a fume hood, wearing thick gloves and a face mask. Below you can see the tape along the edges. This is to keep it from unravelling too much. So what I did was to keep the tape on while I spread, or more accurately, squeegeed (sp?), the epoxy on the back side, then flipped it over and removed the tape and did the epoxy on this side.

Below is the setup in the fume hood. I cut the fabric into the shape of the plate and lay it into the negative, and then put the positive on top.

I used an arbor press for compressive force and cranked it down with two pieces of wood on either side and left it over night.

Here is the plate the next morning. Not too shabby. As you can see the edges are a bit scraggly, so I re-epoxied them.

Lastly, I had a bit of fun with spray paint in the fume hood. Spray painting is so fun, I see why teens do it, but I think it takes a little bit of practice. Gotta work on my tag before I get out there.