GPS Module

Firstoff, all of the props on this part of the build goes to Miraculon.  Specifically, this post on the Weather-Watch forum.  I followed this design for the most part with the exception that I used 3 inch PVC pipe instead of the 2 inch that he used.  Please read this to completion at least once before starting work if you choose to do it this way.

Here are the tools I used to get the housing built:

- Rigid Sawsall with 8 inch general purpose blade (hacksaw would work just as well)
- Dremel with sanding drum
- Bosch drill with angular head (not necessary, the other drill would have worked just as well)
- Craftsman cordless drill
- 1/16, 3/32 and 3/16 drill bits
- 3 inch hole saw (actually, I should have used a 3⅛ inch as I had to Dremel a little bit all the way around to get it to fit in the pipe)
- 24 inch length of 3 inch diameter PVC Schedule 40 pipe
- 3 inch PVC pipe cap
- Wood board (I had some 3 inch wide by inch thick board in the garage.  Thickness of the board should be at least inch in my opinion).  The first hole that you see in the picture was done by a 3 inch hole saw, which left WAY too much of a gap between the board and pipe).
- 1 inch long nails
- Measuring tape and ruler

Here is how I built the GPS unit:

1.  Cut the PVC pipe
- I put the cap on the end of the pipe for reference.  Since the pipe I used was bought in the store, both ends of the pipe are neatly cut and straight.  You do not need to cut a perfectly straight line in order for this to work.  There is 2 inches between the stop and the end of the cap.  If you are off by a little, you'll be OK. 

-  I picked a place to cut that gave me room beneath for the blade to go without touching cement when the cut was done.  IF YOU DECIDE YOU WANT TO CUT IT LIKE I DID (SEE THE PICTURE BELOW), BE VERY CAREFUL ABOUT THE SPEED OF THE BLADE AND THE ANCHOR OF THE PIPE UNDER YOUR FOOT!!!  There were a couple of times that I stopped because things weren't secure.  A better (safer) way of doing this would be to secure the pipe to your workbench with clamps.

-  I used my eye to guesstimate 1 inch (in hindsight, should have been 2) between the bottom of the cap and where my blade was. 

-  I kept the blade parallel to the bottom of the cap at all times.  I started the blade SLOWLY as I began the cut. 

-  Once the initial score on the pipe was done, I sped the blade up a bit to get it through.

Here is a pic sawing the pipe:

-  Once I was done sawing, I had burrs like this all over where the cut was.  They were very easy to get off by running my thumb around the cut.  Those that didn't come off this way were easily plucked off.

2.  Cut the plywood board for the bottom of the mount.

-  Since the board I was using was only inch wider than my drill bit, I had to find the exact center of the board to ensure a correct cut.  Like I said before, the bit I used was too large.  If I did it over again, I would have had a 3⅛ inch hole saw instead of the 3 I used.  I had some Dremel work to do to shave a little bit off my cut so it would fit in the pipe.  Here's a picture of me cutting the bottom piece:

Again...same thought process.  I started my cut slowly and paid close attention to the speed of the drill and the security of my foot on the board.  Also made sure the bit had clearance and would not strike the floor at any time.

- This is the finished product.  Notice the roughness around the edges.  I Dremeled the edges to clean this up.  You could use sandpaper as well:

-  Test fit this into the pipe to ensure it'll fit.  It should be a little snug.  If it's too big, Dremel or sandpaper

- (Optional)  If I were going to mount this outside, I'd probably put a coat or two of water sealant on it just in case.  My mount will be indoors for now so I didn't do that.

3.  Create the cable notch (or you can choose to cut a ⅜ inch hole a little further away from the edge of the bottom piece.

- Mark a vertical line along the edge of the wooden piece.  This will be where you'll notch it for your cable.

-  About ⅛ inch from the edge, I drilled a 1/32 pilot hole all the way through using the Bosch drill.  I made sure the drill stayed vertical.  I then got a 3/32 bit and widened the hole.  At this point, it was close enough to the edge where I gently leaned the 3/32 bit toward the edge and allowed it to dig through.

-  Now that I had a notch on the outside to work with, I got out the 3/16 drill bit and the Craftsman drill and layed the bit on it's side along the notch.  I fired up the drill and moved the bit up and down perpendicular to the edge along the notch to widen it.  Make sure to keep the bit perpendicular to the edge.  Periodically, I'd stop and check for depth and see if the cable would fit in the notch without any of it protruding above the curve of the piece.  If I could still see cable, it wasn't deep enough.  I'd rather be a touch too deep than not deep enough.

-  Here's a picture of the cable in the finished notch:


4.  Nail the bottom to the pipe.

-  I marked off 4 places, 90 degrees apart from each other.  I measured inch up from the bottom and marked there for drilling of pilot holes.  Using my 1/32 drill bit, I drilled the pilot holes enough to get through the PVC.

Finished hardware product:

Side/bottom view:

Inside view:

Ready for circuit board installation: