Carbon fiber money clip class build

Carbon fiber money clip

Back in October I attended a Composites 101 class at Nova Labs. Taught by NL member Bo (an aerospace engineer), the start of class was a short lecture about composites in general, including a show and tell of various bits and pieces he’s collected over the years (a piece of a prototype tail-rotor shaft for a large helicopter was particularly cool).

The second and third parts of class were hands-on where we got to practice working with carbon fiber sheet and epoxy resin. Everyone in class got to make a carbon fiber money clip, and then the class built a wine bottle holder where we utilized honeycomb in addition to many more sheets of carbon. That project also gave us a chance to prepare for vacuum bagging a part.

So, how did we make the money clip?

  • Prior to class, Bo cut several parts from lite plywood and pink foam insulation on the laser cutter. Everyone got a set of these and some nuts and bolts to hold it all together.
  • Stack the parts up and fasten them with the hardware.
  • Prepare the two sheets of carbon fiber, mainly by securing the edge with masking tape, and trimming it down to be just wide enough to hold the edges together.
  • A sheet of acetate (very smooth, thin, plastic sheet) is put on the table, and the mixed resin is spread in a thin layer on the acetate.
  • The first sheet of carbon fiber is laid onto the resin, and then more resin is added on top of it fully wetting out the carbon fiber.
  • Add the second sheet on top of the first, and add more resin to wet it out.
  • Lay the second sheet of acetate on top of your resin-infused carbon, making a goopy sandwich.
  • From here, we bent the whole thing into the jig, and clamped the assembly together to allow it to cure.
  • Due to the time constraints of the class, we didn’t get to finish the parts that day. Bo came in a few days later and cut them down on a bandsaw, and sanded the edges.

While the surface finish of mine wasn’t perfect (I had several little bubbles) I think it came out pretty well for a first attempt.

4 thoughts on “Carbon fiber money clip class build

  • January 12, 2016 at 1:47 pm
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    Awesome! Thanks for the photos and the write-up.

    I’m wondering how the inside of the money clip (what I will call the belly) came out so well without anything clamping against it. In other words, how did the layers stay smashed against each other so well when nothing was holding them together other than the two pieces of acetate? Was there a little piece of the jig that was inserted between?

    Thanks for your help.

    Reply
    • January 12, 2016 at 10:33 pm
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      I think I got lucky more than anything else. When I did it I made sure the 2 layers of acetate were pushed together in that area, but that was about it. There was not anything else like a dowel inserted into that void pushing the ‘belly’ toward the outside.

      Bo, the instructor for this class, has done it several times, and I’ve seen the finished money clips waiting for pickup; plenty are not as clean or tight in this area.

      Reply
      • January 13, 2016 at 12:50 pm
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        Interesting. I was thinking of trying this at home. I’m trying to imagine how the tape was applied to the edge without fibers going everywhere. Or did you just stick the tape on in a square and cut through tape and fibers with scissors? I wish there was a composites class close to me! Anyway, thanks for the help.

        Reply
        • January 13, 2016 at 9:22 pm
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          The tape was applied to the larger sheet of material, and then trimmed down.

          Reply

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