Turtle Sense communicator PVC housing assembly instructions

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Overview

The Communicator (Comm) unit housing is made out of standard PVC schedule 40 white pipe pieces and fittings. There is an upper section which houses the Comm PCB and phone board assembly, and a lower section which holds the battery pack. The pieces of each section are glued together with standard PVC pipe primer and PVC pipe cement. The two sections are attached to each other with a set screw, and another set screw holds the entire assembly onto the PVC pipe and concrete base (or "tower). There are also two wood support pieces which attach the Comm board to the PVC Inside Threaded Pipe Plug.

Materials used

  • 3" Schedule 40 PVC pipe, about 9" total
  • 3" Schedule 40 PVC shallow flat cap, qty 2
  • 3" Schedule 40 PVC inside threaded pipe plug (a.k.a. cleanout plug), qty 1
  • 3" Schedule 40 PVC coupler, qty 1
  • 3" Schedule 40 PVC cap, qty 1
  • PVC pipe primer
  • PVC pipe cement
  • 91% isopropyl (rubbing) alcohol
  • 1/4-20 x 1/4" allen set screw, qty 2
  • Hardwood blocks (such as Maple or Cherry) 3/8" x 4.2" x 1.1", qty 2

Preparing the pipe pieces

  1. Cut one piece of the PVC pipe 5 1/8" long, and another piece 3". A chop saw works best for this.
  2. Put a small chamfer on both ends of both pieces. A power sander or sanding by hand with #36 or #50 sandpaper works well.
  3. De-burr the sanded edges.
  4. If the Inside Threaded Pipe Plug does not fit loosely into the Coupler (very likely), sand off a little of the perimeter of the plug and de-burr.
  5. Using alcohol on a paper towel, clean the outer surface of both pipe pieces, and the gluing surfaces of all the fittings.
  6. Following the "Mechanical - Side View" drawings, drill the holes in the center part of the Threaded Pipe Plug, and carefully de-burr them.
  7. Following the "Mechanical - Side View" drawings, drill mounting holes in the two hardwood blocks.
  8. Drill a 9/32" hole through the flat faces ofthe

Gluing the pipe pieces

Work in a well ventilated area. The general procedure for gluing a joint is this:

  1. Check the fit of the pieces before gluing. The pieces should be able to go partway together.
  2. Apply primer to both surfaces of the joint.
  3. Within a minute or less, apply glue evenly and thoroughly to both surfaces of the joint.
  4. As quickly as possible, join the pieces firmly and hold them in place for about 30 seconds until the joint starts to set. A hammer may help seat the joint completely, but usually isn't necessary.
  5. The pieces can be handled in about a minute, but the glue takes up to 24 hours for full strength.

Following the "Mechanical - Side View" drawings, assemble the pieces together, one joint at a time:

  1. Glue the Inside Threaded Pipe Plug into one end of the 5 1/8" pipe piece. If any glue oozes out the edge, wipe it off or sand it off later.
  2. Glue the Coupler to the 5 1/8" pipe piece, on the same end as the plug in the previous step. G
  3. Glue the domed Cap onto the other end of the 5 1/8" pipe piece.
  4. Glue the two Shallow Flat Caps together, back to back. Use a flat surface with a vertical surface behind it (such as a stair tread and riser), to align the caps when you glue them.
  5. Glue the assembled Shallow Flat Caps to one end of the 3" pipe piece.

Final steps

  1. On the open end of the coupler and the open end of Shallow Flat Caps, drill a 3/16" hole about 3/4" from one end. These holes are for the set screws.
  2. Chamfer both holes, and then tap them with a 1/4-20 tap. Drill and tap the holes after the gluing is done, to avoid possibly gluing the wrong end.
  3. Insert the set screws into the tapped holes with a 1/8" allen wrench.
  4. Drill a 9/32" hole through the flat faces of the back to back caps. Drill the hole just a bit away from the inner face of the 3" pipe piece.