How to build a PAPRa Fan Box (96mm)

A video on how to build the BNC connector:

Strip the red wire on the fan:

Connect the smaller brass component to the red wire:

Crimp the brass component to the wire:

Test that the crimp went well by tugging on the brass component:

Make sure to put the wires through the ground cylinder before connecting the brass component to the connector:

Push the brass component into the center of the connector.

Since the wire is braided, this step can be tricky, and a small item like a paperclip can help push the component into the middle of the connector:

Check that the brass component is visible and flush with the interior plastic column in the connector:

Tugging on the wire should not have the component pull out:

Strip the black wire:

Crimp the ground cylinder to the back of the connector with the black wire:

Another angle of the crimp:

Place the waterproof seal around the edge of the BNC jack:

Place the Fan Outlet Spacer (P-TET-000145) into the fan:

Place the Fan Outlet Spacer (P-TET-000152) into the fan:

Note the orientation:

Begin taping the Fan Outlets into the fan:

Cover all of the air gaps with dryer tape:

Place the base gasket (P-TET-000146) carefullyinto the fan box (P-TET-000140):

Place the Fan Outlet Gasket (P-TET-000) inside the Fan Outlet Spout raised edge (P-TET-000144):

Place the fan outlet spout (with gasket) into the fan box:

Place the BNC jack into the fan box:

Make sure the BNC jack is seated in the hexagonal space:

Place the washer around the BNC jack:

Place and the finger tighten hex nut on top of the washer and BNC jack:

Tighten the hex nut with a wrench:

Place the fan (with outlet spout) into the box, holding the gasket in place:

Push the wires in to the fan box.

Place the Fan Gasket (P-TET-000147) on the Fan box.

Place the filter interface on top of the fan box:

Place 4x M4x16mm screws through the filter interface:

Secure the filter interface onto the fan box with 4x M4x16 screws using a hex screwdriver:

Option to use an impact drill:

Place the Filter Gasket (P-TET-000148) onto the Filter interface (P-TET-000158):

Place the stealth filters into the filter gasket:

Place an M4 square nut into the center space of the Filter Frame (P-TET-000159):

Fastening an M4x16 screw from the opposite side to hold the M4x16mm square nut in-place inside the Filter Frame using a hex screwdriver:

Place the Filter Frame (with M4 nut inside facing down) onto the Filter Interface. Make sure you get the orientation correct and avoiding direct contact with the filter:

Place 4x M4 nuts into the corner spaces of the Filter Interface, screwing in M4x16 screws in the process to secure the Filter Frame onto the Filter Interfac with a hex screwdriver:

Remove the center-piece M4 scew:

Secure the weather guard ontop of the fanbax assembly with an M4 screw using a hex screwdriver:

Insert the MOLLE Strap (P-TET-000153) into the MOLLE Spacer (P-TET-000193):

Secure the MOLLE strap (with MOLLE spacer) onto fanbax with M4x16 screws with 2x M4x16 screws using a hex screwdriver:

Secure the MOLLE Catch (P-TET-000154) between the MOLLE strap and fanbox with 2x M4x16 screws using a hex screwdrivef

Congratulations! You’ve now built a Tetra PAPRa Fan Box!

Changing the filter depends on how much you use the device. If you’re using the device where there are a lot of particulates in the air (such as a construction site or a woodshop), you may want to change every month or so. If you’re using the device where there are less particulates, every two to three months should be fine. HEPA filters just get dirtier and eventually the fan will have a hard time pulling air through the filter, and the filter should be swapped before that happens.

This particular box was built around the Klein Tools p100 filter. Off-brand filters may not be as effective, so be sure that the filter is NIOSH certified.

No, the fan box is not water proof. With the weather guard in place, water should not get into the filter directly, but increased humidity could decrease the effectiveness of the device.

It is important to periodically check that the nuts are tight on the fan box, to ensure that the box is properly sealed against the elements. Hoses should also be cleaned periodically as well.