Robert Moore <<remmoore>>
writes:

Four years ago, I built my first instrument
pod – I called it the Nerf Fairing, because I used a closed-cell foam to create
the body of the pod. I wrote about it here:
http://ozreport.com/forum/viewtopic.php?t=10760&highlight=nerf

The pod worked very well overall. After 4 years, it looks as good
as the day I finished it. There were, however, a few things I was hoping to
improve.

First, the vario was positioned behind the GPS. This meant that at
faster speeds, I had to look behind me to see it. Also, the GPS was far enough
out front that I had to speed up and bank left to be close enough to read the
street names on the moving map. Both were less than ideal.

Second, the connection jacks from the vario to the GPS and wind
vane were somewhat exposed. While it likely makes little difference in terms of
drag, I thought I might be able to improve that in a next-generation pod.

Lastly, (and most compelling) is that I needed a winter-time
project. Frankly, building a new pod was going to be a pure vanity project - I
wanted a new toy, and was prepared to build it.

Pod design had evolved since I built the Nerf Fairing. Dustin’s
pod, for example, is more streamlined than the predecessors; the vario was out
front where I wanted it, and the teardrop shape is quite appealing. There is
nothing available in this style that fits my older instruments, so I would have
to come up with a few tricks of my own.

Over the last few years, I’ve gotten more confident in working
with carbon fiber.  I’m certainly no expert, but my skills have improved with
use. I decided to try building a CF pod. Apologies in advance for not having
mid-process photos.

The first step was to shape the guts of the pod. I used a chunk of
simple packing Styrofoam; shaping it first with a hot-knife, then with my dremel
to get the shape. On the interior, I got a very nice instrument fit by wrapping
them both in sandwich wrap, then placing a strip of mylar around them. I could
then pour an epoxy/micro-balloon mix into the remaining cavity, which left me
with a perfect friction fit on the first try. I used a very lightweight spackle
in some places to correct spots that needed a bit of filler.

The carbon layers were applied in a way I haven’t used before –
laying them directly over the pod, but not wrapping them. It didn’t take much to
get the layers to stay where I wanted – I used a few push-pins if the carbon
didn’t behave. After curing, I sanded each layer to barely expose the carbon,
then applied the next layer. There are four layers at the back – where the most
forces are applied – and each layer extended farther toward the front. Only the
final layer extends the full length of the pod.

Once the carbon was complete, I used a fine brush to apply
additional epoxy over the pod. The interior cavity got only enough to cover the
styrofoam, but the exterior required some additional sanding and coats to get a
nice finish.

 I also built a pivoting mount –entirely from scratch – that
includes a carbon-epoxy body which transitions nicely from the pod. I used
simple hardware store material for the mount that cost around $15.

I didn’t think my carbon work looked good enough to leave it
exposed, so I applied two coats of primer before spraying on a dark-grey
metallic paint job.

I’ve flown with it a couple of times. So far, it does exactly what
I hoped for, gave me a lot of satisfaction in building it, and cost very little
to complete.

The full article with more pictures can be found
here.