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Appendix F


Instructions for Constructing the Push-N-Go

The following table lists all materials needed to build the Push-N-Go. These materials were sourced from online vendors on Amazon and the Segal Prototyping & Fabrication Lab.

Table 7: Materials Used for Construction
Material Specifications Quantity
Pine Triangle 1.5 x 1.5 x .75 in 2
Pine box 1.5 x 1.5 x 1.5 2
Pine Board Plank 3 x 10.5 x .75 in 2
Pine Board Plank 3 x 8 x .25 in  2
Hex Nut ¼-20, Gr 5, ZP 6
Machine Screw M6, Zinc, 10 mm 6
Wood screw #10, 3 in  6
Foam Forearm Rest 27 x 13.5 x 4 cm 2
Bike Wire Brake Cable 6.56 ft 2
Epoxy General Purpose  Single Use Packet 4
Epoxy Steel Kit 10 Oz 1
Steel Compression Spring 42 IB, .105 GA x ⅞ In. x 3 In. 2
Stress Ball 2.5-in Diameter 2
Interior Door Hinge 3-in (76 mm) 2

Note: See Bill of Materials in Appendix B in report for detail on cost and part specifics.

The final construction should appear as below. The following instructions will provide the appropriate information to recreate the Push-N-Go.

 

Installation of the Push-N-Go is provided in Appendix G

The following tools are required to construct this device:

  • Band Saw
  • Palm Sander
  • Drill Press
  • Power Drill
  • Clamps
  • Popsicle Sticks

 

Safety and Skills Required:

  • Epoxy should be used cautiously as extended exposure to the skin may be dangerous. Follow instructions and warnings on packaging for proper use.
  • Band Saw and Drill Press require training by a shop professional and may be dangerous if used improperly or without proper provisions
    • Make sure all materials are fully stable before acted upon by the machine
    • Keep fingers, hands, and other body parts out of the path of the machinery as this may lead to cuts, bleeding, and or additional injuries 

Instructions for Construction:

 

  1. Forearm Rest Board Fabrication
    1. Place hinge on bottom of the board and position
      1.  The pin should hang over the edge, and the metal face of the hinge should lay flush to the wood, and not have overhang on the sides
    2. Trace holes of hinge, remove hinge from board, and use the markings made as guides to drill press holes completely through the board
      1. Choose a drill press attachment with a radius closest to that of the circle traced
      2. Secure wood fully
      3. Punch holes through the wood, adjusting and securing the wood appropriately between each punch
    3. Attach hinge to board with three machine screw and three hexes so hexes are on the underbelly of the board 
      1. Holding the head of the screw flush to the board and immobile, screw the hex nuts tightly with the hand below the board

2. Forearm Rest Fabrication

        1. Unzip mesh lining of forearm rest and insert collar
        2. Holding the collar on the inside of the mesh, poke the cable threw the mesh and screw on the collar so the wire is situated as below
        3. Zip-up mesh lining
        4. Mix two packets of general-purpose epoxy with a popsicle stick on a disposable surface
        5. Apply epoxy with popsicle sticks to 3 x 8 x .25 in pine boards, and bind the bottom of the forearm rest to the board. Let sit to dry for twenty-four hours

 

 

 

 

    Figure 14: Cable Threading                                                                Figure 15: Cable-Forearm Attachment

3. Springboard Fabrication

    1. Trace outline of spring on 3 x 10.5 x .75 in board centered 1.5 in from the end 
    2. Use the drill press to drill into the outline .5 in deep
      1. Compare drill press attachments to the size of the traced outline so they match up within a cm of the trace 
      2. Clamp board down so it is immobile, and position the outline directly below the press attachment
      3. Press down with the drill press, pulling it out of the wood after each .1 in drilled to release pressure, and blow wood shavings off the piece to keep the piece clear

Figure 16: Spring Drill Press

    1. Trace four holes in rollator frame that screws onto forearm rest onto board (5.75” apart lengthwise, 1.75” apart widthwise)
    2. Use the drill press to drill four holes
      1. Compare drill press attachments to the size of the traced outline so they match up within a cm of the trace 
      2. Clamp board down so it is immobile, and position the outline directly below the press attachment
      3. Press down with the drill press, pulling it out of the wood after each .1 in drilled to release pressure, and blow wood shavings off the piece to keep the piece clear

Figure 17: Spring Insertion

    1. Coat the bottom of the hole with mixed steel epoxy and insert spring. Apply firm pressure atop the spring to fix it in place for one minute. 
    2. Let dry for twenty four hours
    3. Coat the top of the spring with mixed steel epoxy and place triangle wood wedges on top
      1. The hypotenuse should point towards the long end of the board, and the base of the wedge should sit flat on the spring 

4. Partial Assembly 

        1. Position the free side of hinge on the forearm rest 5.5 in from the end of the long side of the wood springboard
          1.  * the forearm rest will lay snuggly on the wedge atop of the spring
    1. Using wood screws, drill through the open holes of the hinges in to the springboard wood

*Placement may vary based off on the cut of the wood and components used

Figure 18: Spring Assembly

    1. Wood glue the bottom side of the wood plank, with forearm rest, to the wood wedge atop of the spring
    2. Apply pressure for ten minutes, and let fully dry for twenty-four hours

Figure 19: Forearm Attachment

5. Palm Rest Fabrication

    1. Wood glue bottom of wood box to 3 x 10.5 x .75 wood board centered 4.5 in* from the end of the long side of the plank, and clamp 

*This may need to be adjusted based on the patient’s arm length and comfort preferences 

    1. Let wood glue dry for twenty-four hours, and wipe down excess glue with a wet rag
    2. Glue one stress ball to the top of each wood box with general epoxy
    3. Let all glue dry for twenty-four hours