I've been wanting a gimbaled camera mount for my kayaks, but have been unable to find a commercial gimbal mount that advertises being waterproof. On 3 of my kayaks, I have Scotty Deck Mounts which accept camera mounts, extensions, and other accessories.

My dream is to have a mount that will:

keep a camera level and pointed in a set direction (relative to longitudinal centerline) regardless of pitch and roll.
be strong enough and waterproof enough to survive a kayak roll.
have 360 degrees of rotation parallel to the longitudinal axis of a kayak.

Step 1: Pieces

Scotty Extension
(2) 1/4" 20 tpi 2.5" SS machine bolts
12" 1/4" 20 tpi SS rod
(7) 1/4" nyloc SS nuts
4' 0.75" carbon fiber sleeves
4' 0.25" carbon fiber sleeves
18" 1/2" PVC pipe

Step 2: 90° Curve

The Scotty Extension was cut in two at it's narrowest point

An 18" length of 1/2" PVC pipe was:

split at one end (bottom) to mate with the lower section of Scotty Extension.
split at the other end (top) to accept a 1/4" nylok nut.
drilled at the top end to accept 1/4" bolt.
bent PVC pipe to a 90° curve by heating with a hair dryer.
forced PVC over the lower section of extension by heating PVC with a hair dryer.
spread the top end to accept nylok nut by heating with a hair dryer.

Voids between PVC and Scotty extension bottom were filled with Gorilla Glue (polyurethane adhesive). I borrowed some of my grandson's turquoise Play-Doh for dams to constrain expansion of the glue.

The joined PVC pipe extension was wrapped with carbon fiber and wetted out with West Systems Epoxy. I should have used larger diameter carbon fiber sleeve and shrink tubing.

Step 3: Camera Bolts

Plastic handles (bottle lids) were attached to stainless steel bolts with gorilla glue. Holes were drilled in plastic to supplement the chemical bond with a mechanical bond. Hex shape of stainless steel bolt head was expected to provide mechanical bond for glue to stainless steel bond. The glue - stainless steel bond failed so I later beefed it up with West System 655K G/Flex Epoxy between gorilla glue and stainless steel.

Step 4: Cradle

The cradle was fabricated by wrapping 1" nylon strap with carbon fiber and wetting it out with epoxy. The cradle was shaped using electric tape to hold tight to a jig fashioned from a block of foam. The next day a second piece was added near to and parallel to the bottom. Quarter inch wide slots, for the camera mount bolt, were cut in both horizontal pieces. The slots allow positioning the camera so it hangs level. The space between these two parallel bottoms is large enough for a nylok nut to capture camera bolt when the camera is removed.

Step 5: Cross

The cross was fabricated from 1/2" vinyl tubing wrapped with carbon fiber. The cross over point was beefed up with a wrap of 1/4" carbon fiber sleeve. After wetting out the two pieces were held in place with a jig carved from 2x4 scraps.

Step 6: Cross Support

The cross support was fabricated by gluing a nylok nut and a length of 1/4 stainless steel threaded rod to a piece of fiberglass scrap. Joined parts were wrapped with 1/4" diameter carbon fiber sleeve, wetted out and vacuum bagged. The cross support goes between the 90° curve and the cradle.

Step 7: Assemble

The cradle was attached to the cross with a threaded stainless steel rod and nylok nuts. The cross was held on its support with nyloc nuts. The support was attached to the 90° curve with a camera bolt.

Step 8: TEST

This is a prototype.

The first tests produced video quality that is unwatchable because of the oscillating pendulum motion. After damping the motion by increasing friction, the video was calmed some and a little more watchable.

Step 9: Review

Okay, it kinda-sorta works. The last test with the camera mounted on the bow of the red and white kayak is much better than results from the test on the stern of the orange kayak.

My plan is to continue refining and testing. Adjustment of friction in the gimbal is not very refined or consistent. Adjustment requires using 2 open end wrenches to turn nylok nuts adjusting friction placed on cross tube ends. The connection between the 90° curve and gimbal support is not rigid enough and I've been unable to hold the longitudinal alignment during a kayak roll. Instead of splitting the top end of the 90 curve to capture a nylok nut on the handled bolt it would be better to just attach the cutoff end of the Scotty extension. (Just make the extension longer with 90° curve in the middle)

My test camera, Panasonic TS3, does not have image stabilization and I should probably upgrade it.