Lugs, Chains, and Paddle Blades

With these three modes we explore the natural world around us. The lugs of our shoes, the chains of our bikes, and the blades of our paddlecraft.

This is our archive of amateur exploration.

Enjoy!

Tuesday, April 15, 2014

DIY Kayak -- Strip Building


I'm building my own kayak. It's going to be a lot of work.

And, since I am learning minor details as I complete the project, I'm going to archive the lessons I've learned here. It will be a single post that I edit as I go. I have found other blogs outlining the process, but found it annoying to click through all of the entries.

First, some details. I'm building a Guillemot Mystery racing boat. I pulled the trigger and ordered the forms in late March, 2014. They arrived within a week, about ten big 24 x 36 pieces of paper with full-scale precision drawings of the forms to make the boat. To summarize the process and undermine dozens of hours of work, it's a simple process -- I'm going to build a skeleton of the boat (spine and ribs) and then cover it with really long, thin strips of wood. After it's all set, I'll remove it from the skeleton and seal it. The spine is called the strongback, and the forms are like ribs, or cross-sections of the boat, every ten inches.

I hope mine looks as good as this one!
The result will be a 20 feet long boat that is very light, tippy, and hard to control. It will (hopefully) be very fast. That last detail is the reason I picked this design, and the reason I am willing to put up with a tippy boat that's hard to maneuver.

I will update this post with more steps/lessons as well as images as the project goes on, and grade myself on each of the steps after they're complete.

Here goes:

This form will be 20" from the bow.
Step 1: Glue the designs onto boards. I'm using 3/4 inch thick fiberboard (got it at Pittsburgh's material re-use center, Construction Junction and I'll hopefully be re-using lots of materials for this project) and 3M Super 77 spray adhesive. Already I learned that even though the paper may look as if it's smoothly adhered to the fiberboard, it can still wrinkle and so it's important to spent several minutes smoothing each one out after it's been glued.
Supplies: $9 for the boards, $109 for the designs (inc. shipping), and $10 for the can of spray adhesive)
Grade: I give myself a B for this task. I could have been more careful with the glue and needed to be more diligent about smoothing out the paper.

Step 2: Cut out the forms. I'm using a regular jigsaw to do this. When I cut out the first few forms, the saw shredded the paper near the cut, which made for a rough paper line and in some places the paper even ripped across the design lines. To solve this problem I scored the paper just outside the design lines with an exacto knife so that when the jigsaw shreds it, the paper just pulls away at the score. I could also have tried a different jigsaw blade with finer teeth, but using the exacto knife was easier.
Supplies: Jigsaw, blades, and exacto knife.
Grade: B+

My custom form-sanding set up
Step 3: Sand the forms to their precise shape. I don't have a bench-mounted belt sander that moves up and down like a pro would, so I've made my own (minus the movement). I mounted my vice to a vertical slab of countertop, clamped my handheld belt-sander in it, and built a bench around it out of plywood. Getting the detail on some of the sharper corners may be tricky, especially the end forms.
Supplies: I already had all of this -- Sandpaper, belt sander.
Grade:B+

Step 4: Build the Strongback. This will be a 16'4" long, hollow box made of plywood. Sounds easy, right? It would be if it wasn't necessary that it is absolutely dead-on straight, and the dimensions precise to the 1/16 of an inch (and I'm a total hack carpenter). Of course plywood only comes in 8-foot long pieces, adding to the suspense. As of the end of the summer, I'd built my strongback out of some boards I took out of a basement shelving unit. It was good wood, but with several decades of use, the resulting product was not sufficiently straight (according to two far superior woodworkers). So, I disassembled it and am back to the Step 4 drawing board.
Supplies: Plywood, Drill, Wood screws
Grade:

Step 5: Mount the forms to the Strongback. Most of these will be simple; just screw down a small piece of scrap wood to hold the form in place, and then screw the form to it. However, the two end forms and several of the inner forms that are near the bow and stern must be custom-fitted because their shapes depend on the thickness of the forms I'm using (which are 3/4" instead of the 1/2" used by the designer).
Supplies: Scrap lumber and wood screws
The cove/bead edges fit into
each other without creating voids
Grade:

Step 6: Rip long boards of wood  into thin strips (1/8" for the top, 3/16" for the bottom), and cut cove/bead edges into them. I'll be using either Poplar or Basswood, and will be using a regular table saw with a thin detail blade for the ripping. Then, I will use a router and the proper bits to do the cove and bead.
Supplies: Table saw, blade, boards, router, bits.
Grade:

Step 7: Strip the boat by stapling the strips to forms and gluing the cove/bead joints. This is a long process and will take up most of the time building this boat. And, it must be done twice -- once for the top (deck) and once for the bottom (hull).
Supplies: Lots of glue, staples, and spring clamps.
Grade:

Step 8: Take out the staples and shape the boat. This essentially means make it round by knocking down all the ridges where the strips meet with a spokeshave, plane, and/or sanding.It'll be done separately for the deck and hull.
Supplies: Spokeshave, plane, and lots of sandpaper.
Grade:

Step 9:
Supplies:
Grade

Oct. 2015 Edit: Fuck it. I'm not doing this. I'd rather paddle a kayak than build it. I don't have time for this shit.