Now that we know the circuitry works, let's put everything in its place. We'll use some steel and nylon fasteners as well as a few spots of glue.
Unplug the battery to begin the assembly process. It's safer that way.
- Prepare the PIR sensor and the PowerBoost by attaching six M2.5x6mm threaded nylon standoffs to the printed-circuit board mounting holes with M2.5x4mm nylon screws.
- The longer M2.5x6mm nylon screws will be used to attach the standoffs to the enclosure in a later step.
Mount the components to the interior of the enclosure in the order shown.
1. Fan
- Orient the fan with the wires exiting towards the top of the enclosure.
- Use four M2.5x16mm steel screws, flat washers, and hex nuts.
- Place the washers and nuts on the interior side of the fan.
2. N-Channel MOSFET
- Position the MOSFET so the pins and connected wires are to the right.
- Attach with one M2.5x10mm nylon screw and hex nut.
3. micro USB Panel Connector
- Attach using the included steel screws.
4. PowerBoost 500C
- Position the board with the battery connector towards the enclosure bottom side.
- Secure with four M2.5x6mm nylon screws.
5. Li-Po Battery
- Mount on the bottom side of the enclosure using two very small dots of blue tack putty.
- Wait to plug the battery wire into the PowerBoost until all components are installed.
6. PIR (Motion) Sensor
- Orient the sensor with the two adjustment controls facing outwards.
- Attach to the right side of the enclosure using two M2.5x6mm screws.
7. On/Off Switch
- The switch mounts using its threaded shaft.
- Remove the outer nut and lockwasher.
- By hand, spin the lower nut onto the shaft as far as it can go. This will provide a longer shaft outside the enclosure.
- Insert the switch shaft into the hole in the enclosure's back panel.
8. USB-A Panel Connector
- Attach with the included steel screws.
At this point, all the primary components are attached. Re-connect the battery to the PowerBoost and test to see that the extractor is working properly.
- Set the PIR sensor's duration and sensitivity adjustments as shown. This level of sensitivity will detect movement within about 5 feet of the sensor. The fan duration at this setting is approximately 60 seconds.
Next we'll attach the filter support rods, the prismatic window plastic, and finally the activated carbon filter material. Almost done!
- Using a fine-toothed saw, cut two 1/8 inch acrylic rods to a 2-5/8 inch length.
- Dry-fit the rods in the mounting holes and check for a proper fit; the rods should fully nestle into the u-shaped holes.
- Test that the front panel fits correctly with the rods in place. Use a small file to adjust the rod holes as needed.
- Place a very small drop of gel super glue in the bottom of each hole as shown. Do not put any glue in the front panel's rod holes.
- Press the two rods into place and hold for 30 seconds until the glue sets.
- Allow the glue to cure for at least 15 minutes before handling.
- Cut the 1/8 inch thick prismatic plastic sheet into a 1-3/4 by 2-1/4 inch rectangular window.
- Dry-fit the plastic window to the underside of the front panel to assure a proper fit.
- Apply a few very small dots of superglue or acrylic cement to the underside of the front panel in areas that won't show.
- Press the smooth side of the plastic window in place against the underside of the front panel.
- Set aside until the glue cures.
- Cut a single layer of the activated carbon filter material to the dimensions shown.
- Place the filter material over the large opening in the front panel. It should fit snugly. The acrylic rods will hold the filter in place when the front panel is attached to the enclosure.
