Skin is On

After a few trials and errors I finally sewed the skin on my sof kayak. It only took two years of the kayak hanging under our deck in order for me to start the process. I guess I’ve been busy. A bachelors degree, half of a masters degree, and a new career will do that to a guy.

When I first started to sew the skin I had a lot of troubles. I decided to use the method show by Cape Falcon Kayak. I bought 8oz ballistic nylon from George Dyson in Bellingham, which was an interesting trip. The first step was sewing the end pockets, which was easy.

The problems started with the cutting of the nylon fabric. I put a strip of wood down the middle of the deck but i found that the nylon moved a lot while cutting. I virtually had no idea where I was cutting the cloth. Next time I do this I will tack the skin to the gunwales before cutting.

My first attempt at sewing the main seam was pretty bad.

I then made calls for help across the internet. I decided to continue with whip stitches but I would soak the nylon while sewing, thereby giving me more cloth to work with and allowing the skin to tighten immediately after drying. For the most part this worked well. I still managed to have a couple of wrinkles along the sides of the hull. I don’t know if this is common or not, and how much it will affect the paddling.

There is some bunching in the center of the cockpit, and I assume that will not be a problem for when I stitch in the coaming.

I’m still a bit hesitant in coating the kayak with polyurethane. I don’t want to spend a lot of time and money coating the kayak in case one of the following fails:

  • little holes caused by the stitching, will they get sealed?
  • are the wrinkles going to cause problems?
  • will the seams hold?

Time For Another Interlude

Over the past couple of weeks while waiting for the weather to warm up for fiberglassing the canoe, I had the chance to work on the SOF kayak. I’ve actually pretty much finished the frame and just need to set aside some time for sewing the nylon skin. There were several little things that I did to the frame to get it ready. In no particular order:

1. cut out the coaming base plate, riser and rim, and fiberglass the rim for extra support and longetivity

2. add extra supports for the coaming base and station behind the coaming where a lot of weight will be put on when getting in and out of the boat

3. putting small decks on the bow and stern, and filling the ends with some hardwood, then shaping to a smooth round nose

4. adding 1/4″ thick and 1″ wider station in front of the coaming because I thought my initial station was a bit weak

5. epoxied foot rests on to the chines

And voila! pretty much ready for the skin

The Pygmy Tern 14 Launches

Well, several months after finish the kayak we finally got it into the water two weekends agp. Such is life when you are busy with little kids!
We had a successful launch, although the cheap champagne that was poured was pretty skunky. If that’s the worst thing that happens with this boat we’ll be happy.
My wife took the kayak out for a little paddle, along with her new Holst GP. She was happy with the pair although it sounds like she’ll need some time to get used to the two. The Tern14 had a looser feel than what she was used to (stability, not tracking). I also gave the kayak a quick paddle. It seemed pretty quick and tracked well but I can’t compare it to anything really. I’ve only whitewater paddled until this weekend. I didn’t try to maneuver the boat too much as I wasn’t used to the Greenland paddle. I did manage to roll the kayak on my first attempt so I suppose that means it rolls pretty easy (I haven’t been in a kayak in about 5 or 6 years).
Beach shot #1
Beach shot #2
Here are some thoughts on the boat. First, it looks very nice and seems to have a lot of potential for paddling. It’s relatively comfy, the seat works good, and the secondary stability is rock solid. My two biggest gripes with the boat have to do with the coaming and the hatches. We found it difficult to yank off the spray skirt with one hand. Lifting the tip of the skirt up and out was not enough to release the skirt from the coaming lip, the skirt would still catch/hold at about 11:30 and 12:30. Flipping the skirt off with a second hand was easy, but then you’d have to let go of your paddle. This definitely needs some adjustments, I’m surprised that it was so difficult. Secondly, the hatch covers don’t seem to fit super great. They do not sit flush with the deck and after a few rolls and wet exits there was some water in the bulkheads. I think part of the problem is with the way the foam lies on the hatch lip. At the very tips the foam perhaps bunches up by a mm or so, and maybe this is enough to keep the whole hatch from being as tight as it could be. I left the hatches on the kayak for a long time, thinking that the foam may compress. However, I think a bit of work may be needed. Perhaps I will try to notch or cut away a bit of foam on the ends. Any input is welcome on either of these issues!

Interlude, part deux

I now basically have the frame together for the Interlude.
gunwale scarf
Here is a list of some of the issues I’ve encountered during the build.
1. I needed to clamp/jig the keel to keep it straight while putting the boards onto the frames
keel clamp
2. thickened epoxy was used to hold the boards to the frames and it seems to be strong
3. after the epoxy cured, I drilled holes and inserted 3/16″ dowels to pin the boards to the frames. I used PU glue to hold the pins
dowels glued
4. I found it very finicky to cut the board ends (chines & gunwales) in order to meet flush with the stern and bow plates
close but not tight
5. the bow and stern plates are epoxied in place with dowels
6. I had to remove two knots in my chines, and filled these holes with thickened epoxy
7. I’m not sure if my frames are deep enough, maybe I should add some extra support…?
8. I’m not sure exactly how I will finish off the bow/stern plates. It looks like other people add small deck plates to tie/hold everything together
9. I’m not sure what I’ll use to seal the wood. shellac? polyurethane? tung oil? epoxy (too expensive)?

Interlude: building a Sea Rider SOF

Prior to starting the stripping on the Freedom 15 canoe, I thought I’d try and rig together the frame of a skin-on-frame kayak.

I had come across Tom Yost’s website and found a ton of good information on his SOF construction method, along with several different kayak designs. It’s an unbelievably good source of information. Through a small amount of research and a few emails with Tom Yost, I decided to build his Sea Rider. As I have had this in the back of my mind for some time, I had already purchased nylon and cedar for the kayak. I did this last year while working on the Tern 14 for my wife. I figured that I would want a kayak in case we had a chance to paddle together, and a SOF would be the cheapest and fastest way to build a kayak for myself.

Earlier this year I transferred Tom’s offsets into my CAD program and printed out templates for the stations. I then cut the stations out of some extra 1/2″ plywood I had kicking around. This was a bit of a mistake because the plywood turned out to be of very low quality. The surface was so rough that it was difficult to trace the proper outline on the wood, and the wood had a tendancy to grab the saw when cutting which made it difficult to make precise cuts. As well, there ply had a lot of voids in it. I tried to fill in the voids as best as I could with thickened epoxy. So after all of the tracing, cutting and sanding I was almost ready to put the frame together. I also needed to rip the planks for the frame and scarf them together. I started with a 1x8x10′ wrc board and ripped it to make the chines and keel (1x.5×20′) and gunwales (1.5x.5×20′).
My first shot at putting the kayak together went okay. The keel is curved, so I’ll have to fix that before I glue everything together. I may also try to clean up the scarf joints a bit better before continuing.
curved keel

BTW, I chose the name “Interlude” because that is exactly what this kayak is. It’s an interlude in the building process of the canoe. Pretty imaginative eh.

Steam bending stems for canoe

I finished steam bending the stems for the Freedom 15. It was really easy. I grabbed our kitchen kettle and taped down the on switch to keep the kettle boiling. Over top of the spout I placed some ABS tube with my stem pieces. I didn’t worry too much about stuffing rags around the spout to trap the steam. The kettle was ejecting steam in all sorts of directions. The top end of the ABS was already sealed with a cap. In fact, the ABS I was using is actually my home made rod case for our 8wt fly rod. After 20min of steaming I grabbed the strips and slapped it on the stem mold. The wood bent extremely easy. Time really wasn’t an issue. All I had to do was clamp one end, pull the strips down and put on more clamp on. Voila. After that, I put more clamps just to secure the whole thing and to minimize recoil.

My stems consist of three strips of wrc for the inside, and walnut/AYC/walnut for the three strips for the outside stems. I’m not sure why a person would need hardwood for the inside. I’m not even sure why you need hardwood for the outside, the whole thing is wrapped in fiberglass and epoxy. I guess it doesn’t hurt, and I hope the AYC stands up to the abuse. One of my wrc strips actually cracked during the bending. I’m not sure why, but maybe there was a knot in it. I didn’t use particularly great wood for the insides stems.

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