1st Petal Prototype

							           1st Petal Prototype
• Fabrication completed October 27, 2008
1st Prototype Components
                       Weights
• Weights of components are summarized
  below
• End-closeouts were aluminum for this
  prototype, would not be the case for real
  object (carbon material)             Item
                              Carbon fiber facings
                                                   Weight(g)
                                                         61
                                       Honeycomb          16
                                       POCO foam          27
                                       SS Tube            32
                                       Epoxy              30
                                       CGL                30
                                       Carbon tubes       15
                                             Subtotal    211

                                       Closeouts+pins     43

                                             TOTAL       253
   2nd Prototype – Proposed Changes
• Add a bit more honeycomb(gap to side carbon tubes too large)
• Grind honeycomb flat before gluing to facing.
• Grind honeycomb to thickness after gluing one side to facing to improve
  thickness uniformity. Demonstrated on prototype piece
• Small increase in length of POCO foam(right up to outer closeout)
• Bond POCO foam/tube assembly to facings with Hysol 9396/30%(or more) BN
  instead of CGL-7018 => make rigid connection between foam and facing. Use
  bond-line control (the equivalent of 75 micron little shims)
• Modify U-section of POCO foam to allow for tube contraction as result of the
  above
• Reduce size of closeouts
• Bond closeouts with bond line control(glass beads)
• Decide about precision location of carbon tubes – try it on this prototype?
• Some minor tooling modifications to make assembly easier

                    Currently scheduled for assembly Dec. 1-12