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The carbon fiber cutouts are the pieces of carbon fiber used in the tip-to-tip layup, which consists of laying plies from the tip of one fin, over the tube in between them, over the tip of the next fin (and repeating for the other three sides). The preparation for the tip-to-tip layup involves cutting out squares of carbon fiber and attaching them to wax/parchment paper using spray glue. The purpose of the paper is to prevent the carbon fiber from warping when it is being handled. Then, the actual shapes are cut out using a laser cutter. In general, fiber glass can fiberglass can not be cut on a laser cutter, but carbon fiber can, as long as the fiber is dry (i.e., not "pre-preg", referring to sheets of fiber that have already been impregnated with epoxy). Make sure that whichever laser cutter you use can fit the largest cutouts (the CSAIL laser cutter has a width of 18", too small for the final layer of the tip-to-tip cutouts). 

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1. *Using tape, mark squares of carbon fiber (24 squares, 4 for each size cutout, making sure there is enough room to fit the cutout with ~1 inch margin on all sides) using the following table:

   Cutout Number	Dimensions of CF square
   1 (smallest size)	18" x 20"
   2	18" x 20"
   3	18" x 20"
   4	18" x 20"
   5	18" x 24"
   6 (largest size)	20" x 24"

2. Cut along tape and label which size cutout it is (1-6) on the tape so you keep them organized later when laser-cutting.   Next steps tell you to attach wax paper, but wait until after laser-cutting to do this because wax paper burns in laser-cutter
3. Prepare 25 (24 for the cutouts, one extra) pieces of wax or parchment paper (if paper is too small, tape the pieces together so that they are the same size or slightly larger than the carbon fiber squares
4. On the extra piece of wax/parchment paper, use spray glue to test to see how far you should hold the glue from the wax/parchment paper so that when you spray, the paper just barely sticks to your finger. If you use too much spray glue, the carbon fiber will be difficult to remove from the paper and the fibers will be warped, ruining the tip-to-tip layup.
5. For the rest of the 24 pieces of paper, lightly spray the wax or parchment paper with spray glue. Use your finger to see if it just barely sticks to the paper. 
6. Carefully take a piece of carbon fiber (one of the squares you cut out earlier) and lay it gently onto the wax/parchment paper, smoothing out any imperfections and making sure the piece is square (and not warped into a diamond or other shape). 
7. Laser-cut carbon fiber 
   1. Select proper settings for carbon fiber (100% power, 4% speed)
   2. Select proper file (make sure the size of the carbon fiber square matches with the cutout file- this is why labeling the carbon fiber earlier is important)
   3. Place carbon fiber in bed of laser cutter
   1. Make sure there are no loose pieces of wax/parchment paper curling up, as this will get in the way of the laser-cutter
   2. If you have room, weigh down the carbon fiber (but only after testing the path of the laser cutter, or you may damage it if it runs into the weight)
   3. Turn on the exhaust
   4. Cut! (Start with a test piece to make sure it's being cut properly) You may have to cut twice, so make sure you don't move the carbon fiber or the cutout will be messed up when you cut it for the second time.
   5. If you see small areas smoldering (meaning slightly glowing, NOT a flame- fire is bad), keep the laser cutter door shut and wait until it extinguishes. Opening the door would cause oxygen to enter and the smoldering to get worse.

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Waited to cut excess off peel ply, release film and bleeder fabric until started vacc bag 

5. Tip-to-tip Layup

TALK TO PROF. MARK DRELA before doing the layup. He will have tons of tips (because the below procedure may very well not be ideal- also do research to see what works for other teams, and look up Jim Jarvis guide on the internet). For example, it may turn out that we should apply the dry cutouts to the fin can BEFORE adding epoxy instead of AFTER. Who knows??

Required Materials:

• System 3000 High Temp Epoxy Resin + Hardener
• Squeegees
• Popsicle sticks
• Epoxy boats or paper cups
• Paint rollers (LINK)
• Acetone
• Shop towels
• Scale
• Respirators
• Gloves
• Large sheet of Mylar (to protect surface from epoxy during layup)

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