Sorry I haven’t posted a update on the build for a while. Has it been almost 3 weeks?! I’ve been busy with other stuff and these blog posts do take a bit of time to write. I have been working on the “Neytiri” Night Heron. It’s all the stuff that needs to be done before I can bond the deck to the hull. Over the next few days I’ll get you up to date.
First up: forming the carbon fiber skinned recess for the cockpit coaming.
Work from 10/18/10 to 10/25/10
With the deck stripped and sanded I could now turn my attention to the next big construction item: forming the cockpit.
The stock plans for the Night Heron have a nice modern “key-hole” style cockpit opening: 29-1/2″ long by 16″ wide. It’s a great size for your average paddler. My customer though isn’t average by any stretch of the imagination (and he’ll tell you so!). He prefers the small “ocean” style cockpits. They’re closer to the traditional openings found on Greenland skin-on-frames. To get in you have to slide in with both feet. It’s easy once you get used to it. They can offer a better connection with the kayak. The size/shape he picked is close to the one found on his old Valley Canoe Products “Anas Acuta.” It’s almost 10″ shorter at 20″ long by 15-1/2″ wide.
From a lesson learned while building the guitar a few years ago, I made a 1/2 template of the opening for layout and construction out of some 1/4″ plywood. It’s so much more rugged and accurate than a piece of paper or posterboard.
To facilitate easier lay-back rolls, my customer wanted cockpit coaming recessed so that the lip would be even with the aft deck. It’ll be made in carbon fiber to match the sides and is central to the overall design. The faceted sides of the deck wouldn’t allow me to use use my foam trick making the recess, riser and lip in one operation. I’d have to do things differently, more like how I build my wooden cockpits. I’ll strip a flat recess, then add a riser and the lip.
Using some scraps of wood, some clamps and screws, I laid out the profile of the recess. I originally aimed for a recess that was straight from the back to front, making the coaming flat side to side and front to back. The faceted sides made that impossible. It was a trial with a lot of error but I finally got a pleasing shape in both plan and profile with about a 1-1/4″ concavity. That’s less than the Anas Acuta. I cut it out to the line and sanded it smooth. I then stripped it using some nice wide white cedar and sanded that smooth.
The riser will be made in two pieces with an inner and outer ring. The outer ring will be bonded to the recess. The inner riser and lip are going to be cast in one piece so that they slide into the outer. First I made a female form for the inner riser and lip out of plywood that follows the concavity of the recess. I I also took the extra time to fair and paint it super smooth. The goal being to reduce my sanding late. I’ll also be able to reuse it on other projects. The size and shape are very popular. I may even offer pre-made carbon fiber coaming “kits” for other home builders.
To make the outer lip I built out the form with a few layers of pvc fabric and packing tape. I wanted to get the total thickness close to the finished inner riser. I then laminated the inner riser with strips of carbon fiber and fiberglass. It doesn’t need to be be very thick. It’ll get more layers of carbon fiber and fiberglass when it gets attached to the recess. When it had cured I popped it off and trimmed it roughly to height. I took the template and traced the outline on the recess. I offset the line to account for the thickness of the inner and out risers and cut it out to the line.
I dropped the outer riser in the hole and tacked it in place with a few beads of hot glue. A fillet of epoxy all the way around will permanently bond it. After the fillet had cured I sanded it smooth. I masked off the edges of the sapele deck around the recess and laminated on a layer of carbon fiber to the recess and the riser. The carbon is for show and gives incredible strength to the riser. When I ‘glass the inside, I’ll wrap a layer of glass onto the inside of the outer riser.
But that’ll be a later post…
Next up: the special carbon fiber deck trim.