Integrate Piston Cup Assembly

Rule: if you are not directly helping with integration, you must be dancing.

NOTE: Should write separate procedures for pathfinder. Specifically related to the height that the whole assembly needs to be.

Materials: Diaphragm, Cup, 4x grub screws, 7/64 hex wrench, piston, elbow fitting, plug, FireBolt XL, Payload Bulkhead, 8x 3/4" 1/4-28 bolts, Avionics Bay (Coupler), eye nut, castle nut, cotter pin,

  1. Screw diaphragm into Cup with four grub screws using a 7/64 hex wrench

  2. Make sure that the piston rod is fully extended.

  3. Integrate the T-fitting into the piston's inlet port (nose cone side, blunt end) with 2x plugs and 2x FireBolts, a pair on each side. Make sure the T bar is horizontal with respect to the end plate.

    1. Insert detailed BP procedure here
      PROPOSED CHANGE FOR HARDWARE REV: Integrate the T-fitting into the piston's inlet port (nose cone side) with an elbow fitting, plug, and Jumbo FireBolt.

  4. Screw the Payload bulkhead into the top of the piston using 4x 1/4-28 bolts that are 3/4 inch long. You need a 3/16ths hex key.

  5. Insert Avionics Bay

    1. Insert detailed AV Bay procedure here

  6. Put the coupler over the piston and screw in the lower bulkhead. The switchband should be on the nose cone side.

    1. The milled face of the lower bulkhead should be internal to the Avionics Bay.

    2. Screw in with 3/4" 1/4-20 screw.
  7. Screw the piston into the diaphragm

  8. Put an eye nut on the piston.

    1.  PROPOSED CHANGE FOR HARDWARE REV: Add a castle nut on the piston rod and insert a cotter pin.
  9. (Stand in step for CRIMP) Tie a piece of paracord to the eye nut. Tie a knot on the other end.
    1. NOTE ON HARDWARE REV: If the new eye nut is too large to put a quicklink around, consider milling the eye nut down, sewing a piece of webbing onto it, or otherwise just doing something more professional than "tie a piece of paracord." 
    2. Secure a 1000lb quicklink to the paracord, followed by a 1500lb swivel and another quicklink.
      1. PROPOSED CHANGE FOR HARDWARE REV: See if you can't sew at least one line directly onto the swivel?
      2. POTENTIAL CHANGE: Perhaps everything should have its own swivel?
  10. Coil the booster–mission package webbing and stow in several small infinity wraps using minimal tape. The optimal height of the infinity wrap is a little over 1". Leave enough slack (i.e. do not infinity wrap) on one side to extend the lines from the diaphragm to the forward closure.
  11. Attach the booster-mission package webbing to the at the diaphragm quicklink.
  12. Attach both Tender Descenders in series to the quicklink attachment point. Attach the drogue riser onto the second Tender Descender quicklink. For the time being, leave the line on the outside of the cup.
     
  13. Coil the main riser and stow in several small infinity wraps using minimal tape.
  14. Attach one end of the main riser onto the quicklink attachment point. Attach the other end to the packed main parachute.
    1. Pack the coiled riser behind the main parachute (towards the nose cone) inside of the cup. 
    2. PROPOSED CHANGE: Add a section on packing the main parachute before this.
     

  15. Put the airframe tube over the assembly. You may need to move the drogue riser and mission package to booster webbing out of the way.

    1. “Struggle with clocking” - Jakob, 11:20am

  16. Screw in four ½” 8-32 screws to attach the airframe to the Avionics Bay.
  17. Attach the drogue riser to the packed drogue with a 220 lb quicklink. Coil and stow excess drogue line (if necessary) and pack everything into the booster section.
  18. Coil and stow excess mission package to booster webbing and secure with a small amount of painters tape. Place this in the booster section. Then attach the mission package to booster webbing to the forward closure with a 1000lb quicklink, followed by a 1500lb swivel, and then another 1000lb quicklink.
    1. PROPOSED CHANGE FOR HARDWARE REV: See if you can sew it onto the swivel.
  19. Now, attach the other side of the mission package to booster webbing to the forward closure

  20. Screw in the nosecone with the right clocking using four 8-32 screws.

  21. Put the mission package assembly on the booster and secure with 3x 6-32 shear pins. For the Pathfinder vehicle, you will need to skip every other hole.

Notes from integration:

  • Need to turn down upper counter torqued nut on piston because it otherwise doesn’t screw far enough in?

  • We would rather have the piston cup assembly be too short than too long because we can only compress it so much when we do the last step.

  • Consider switching to words like "fore and aft" instead of "up and down"

  • Purchase 1/4-28" bolts that 3/4" long.

  • Cut the mission package to be 25" long.

  • Avionics bulkhead outer rim should be shaved down a little bit–does not fit with mission package tube.

  • Get torque specs and think about them.

  • Add notes about the dental tool.

  • Think about access to diaphragm area for screwing lines when doing mass saving cuts

  • Think about standardizing clocking marks and directional marks

  • Purchase 6x 8-32 grub screws
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