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NOTE: This page will likely be later updated so that each major sub- assembly is a separate page

Sub-assemblies

  1. Motor


  2. Piston


    Materials

     
    •  

      1/4 in torque wrench

    •  Integrated Firebolt
    •  Multimeter
    •  Teflon tape
    •  1/4 NPT plug 
    •  Safety goggles
    •  Gloves
    •  Scale
    •  Weigh boats 
    •  Popsicle sticks
    •  Elbow joint
    •  Tee fitting
    •  Adjustable wrench
    •  Vice grip/pliers
    •  Plug

    Procedures

    1. Using a 1/4 inch torque wrench, ensure that the bolts holding the piston together are very very tight. If the bolts are loose, the piston will lose pressure as it extends.

    2. Use multimeter to check continuity of Firebolt (should be about 1.0-1.4 ohms) and twist the wires to short it. Two people should visually confirm that it is shorted. Wrap the Firebolt with five wraps of Teflon tape. Use pliers to screw firebolt into the NPT plug.

    3. Everyone put on safety glasses. From now on, everyone within the vicinity of the pyrotechnics must wear safety glasses.

    4. Measure out the appropriate amount of black powder into a weigh boat (will vary over testing matrix) and pour it into the other side of the tee fitting, holding over a weigh boat. Seal the opening by wrapping over the head and opening three times with Teflon tape.

    5. Compress the piston completely!

    6. Screw an elbow joint into a side female end of the tee.

    7. Wrench the elbow and tee assembly into the inlet hole of the piston with 5 wraps of Teflon tape until extremely tight and turned upright.

    8. Screw a 1/4 NPT plug into a female end of a 1/4 NPT tee adapter.

    9. Seal the open female end of the tee fitting with another plug (filled with appropriate black powder).

       


  3. Payload - NC


  4. AV Tower

    1. Assembly Procedures for the Hermes II Avionics Tower

       

       

  5.  Soft Goods

     

     Materials

     
     
    •  

      Parachute Packing Box (shot bag, line holder, extra lines)

    •  Sandbags
    •  Rubber bands
    •  Soft goods
    •  Swivels box
    •  Flathead screwdriver

    Procedures

    1. Fold Main (also may refer to Hermes Parachute Packing Procedures)

      1. Tie main parachute down, at the vent and at the end of lines, applying moderate tension.

      2. Gather 8 lines and put them into the lines holder with weights, so you can focus on the other 8 lines.

      3. Go through each line and gore, inspecting gores for tears

      4. Pleat gores so middles are together and put the lines in the holder as you go.

      5. Once you've nicely folded one side (8 lines and gores), weigh down with sandbag and fold over other side to repeat 

      6. Fold up base of parachute towards middle in a triangle pattern

      7. Fold the wider sides of the parachute in towards the center line, using sandbags for assistance


    2. Pack Main

      1. Untie top of parachute from tension

      2. Pull vent to bag bridle through the inside of the bag and the hole at the end. Secure bag handles and vent to bag bridle with a quick link.

      3. Pull the inner layer of flaps forward Fold down the line-holding section of the bag so the bag is partially inside-out.

      4. Z-fold the parachute and pack it into the bag.

      5. Once the entire parachute is in the lower portion of the bag, securing secure flaps using the locking loop and locking pin.

      6. Fold lines into bites, secure two bites with rubber bands on both ends. Secure spectra Main Riser (Spectra) in z-fold with 2 rubber bands.

      7. Pack lines into lines line-holding portion of the main bag and secure locking loop

    3. Pack Drogue

      1. Similar to main

      2. Secure flaps with banding system (TBDto be tested)

      3. Figure 8 Coil lines into infinity loops, pack lines into side pocket.

    4. Coil lines

      1. Get green swivels/hardware box and lines and risers

      2. Drogue riser (infinity loops)

        1. Attach eye to eye swivel

      3. Motor section riser (2 coils, (infinity loops)

        1. Attach fork to fork swivel using motor riser loop

        2. Tighten forks hard!

      4. Mission package riser ((infinity loops)

        1. Attach smallest swivel


  6. Mystery Box

     


  7. MP Assembly

     Materials

    •  Hard goods box (6-32 bolts, 4 1/4-28 bolts, 4 1/4-28 bolts with washers, 3 chamfered 6-32 bolts, eyenut, cotter pin, 10-32 nuts, quicklinks)
    •  Integrated piston
    •  AV tower
    •  Recovery guard
    •  Payload stack
    •  Payload bulkhead
    •  NC coupler
    •  Antirotation rod
    •  Skinny god nut
    •  Integration stands
    •  Tender descenders and loops
    •  Black Powder
    •  Gloves
    •  Popsicle sticks and weigh boats
    •  Goggles
    •  Paper funnel
    •  Scale
    •  Hex key set
    •  Needle nose pliers
    •  Adjustable wrench
    •  Clocking tool

    Procedures


     

    1. Attach AV tower to payload bulkhead with 6-32 bolts

    2. Attach integrated piston to payload bulkhead with ¼-28 bolts

    3. Wire piston to AV tower

    4. Attach recovery guard to piston using ¼-28 bolts and washers **orientation matters will update

    5. Attach payload stack to payload bulkhead

    6. Attach nosecone coupler using 3 chamfered 6-32 bolts, attach nosecone

    7. Integrate soft goods and Tender descenders **Will update with line diagram 

      1. Another QL at end of MP Riser to Motor Section Riser (wide Black) and Main Riser (Blue Spectra)

      2. Main Bag Bridles and load-bearing riser to QL to a 1500 Swivel to drogue riser

      3. Drogue riser to QL to drogue lines

      4. Connection from bottom of drogue bag to Motor Riser

      5. Other end of Motor Riser to loop to swivel to loop to eyebolt

      6. For Tender Descenders from Main Bag TD loops to eyebolt:

        1. Wear goggles and gloves to measure appropriate black powder using weigh boats, scale, and popsicle sticks

        2. Hold TD loops in place

        3. Use funnel to fill TD with black powder

        4. Push the two pieces of TD together

        5. Repeat with second one

    8. Tender descender: Just follow the picture it’s super complicated. Tighten all quick links with a wrench

    9. Screw antirotation rod into diaphragm with locknut

    10. Attach diaphragm. Screw on skinny god nut and place diaphragm on. Next screw the eye nut on and insert cotterpin. . Finally, hold the skinny god nut with small pliers and screw the eye nut tight. Fold down and gaff tape over the spikey bits of the cotterpin!

    11. Set up integration stands. Stand piston-diaphragm assembly and cup close to each other.Thread main bag with lines and tender descenders through cup, so tender descenders are close to the diaphragm. Pull tender descender wires through half-moon shaped hole and attach tender descenders to eye nut.

    12. Push cup (with main bag, TDs and lines) onto diaphragm and secure with 10-32 nuts

    13. Attach swivel (on motor riser) to quick link on top of main bag

    14. Quick link drogue to drogue riser


Integration Order

Ideally, the piston, AV tower, and payload stack can be assembles in parallel and then each attached to the payload bulkhead. In parallel to this assemblage, the nosecone and mystery box can be integrated. Then the two groups would be integrated together with the soft goods and the fin can.

 

Soft Goods Assembly Pictures

 

P


MP Assembly Pictures