After having watched Brian’s first episodes, I’ve decided to go for this challenge: building an F1 kayak. I must say the “prep” work was pretty hard: finding the right wood (WRC, green oak) and cutting to length took me several days. Since I don’t own a table saw myself, I bought the wood cut to size from a local specialty wood shop. I then cut the spreader forms from a multiplex board, according to my size.
Before continuing the actual build, I wanted to make the steam-bent coaming ring. I thought it was a good exercise before steam-bending the ribs. I made it from kiln-dried oak, obtained from the local DIY-store, as I didn’t have access to freshly cut (green) oak. The first try went pretty bad: the strip broke after bending >45°. I therefore decided to soak the planks in water for 5 days before steaming them for 15 min. This helped and I achieved a pretty good coaming:
Bending the arched deck beams was pretty straightforward though:
April 2020: the hardest part: steam bending the ribs…
After the prep-work was done I finally started assembling the deck. This was really the most enjoyable part: using artificial sinew and wooden dowels it was really cool to connect the deck beams.
Bending the ribs was a bit harder though…As I said previously I didn’t have access to “fresh oak” in my region. I’ve contacted a local lumberyard and they offered me oak planks at €6 each, which I found too expensive. Luckily my father-in-law still had some oak planks from his living room flooring project. I soaked the planks in the bathtub for 2 days:
Yet the results were very dissapointing again after 15min of steaming:
I then took a more radical approach and decided too soak the planks in water for two more weeks. I also decided to use a rigid, aluminum backing strap to reduce elongation in the planks on the outside of the bend:
The planks then went in the steam box for about 12 minutes. I put four planks in at 3 min intervals to increase efficiency and to be able to bend all the ribs quickly enough so that I was able to adjust adjacent ribs to make a smooth curve. And voila: by combining sufficient presoaking and using a backing belt I managed to get pretty good bending with air-dried oak.
I immediately added the stringers to make sure the ribs dried in a way that resulted in a smooth curvature.
I then added the secondary stringer. The video suggest attaching it with woodend dowels, but in this case I decided to simply glue it on (I figured that creating to much holes in the gunwales might compromise its strength):
Now I just needed to add the two short back stringers and the single front deck stringer, again using wooden dowels and stringers. I added wooden floorboards, sewn to the ribs.
Be careful if you consider adding these floor boards: they should be thin enough so they don’t touch the fabric, otherwise the skin will stick to it, once you apply the coating (I speak from experience). Also, make sure that the end of the slats do not project beyond the last rib. An overhang could create a lip that can snag your shoes and prevent a quick wet exit! I got this tip from Christopher Cunningham’s excellent book: “building the greenland kayak”.
Assembling the frame was really fun and the video’s were excellent. To protect the frame I applied two layers of boiled linseed oil.
May 2020: skinning and coating the kayak
The time has come to cover up that beautiful frame with fabric. I got nylon fabric from Marcin Bober, a friendly kayak-builder in Poland. It’s supposed to have both good strength and shrinking capacity. Purchase (€90) and delivery went smoothly. First the fabric was laid over the frame and roughly cut to size. I then sewed a “pocket” on either side, as in Brian’s videos, sewing it 8cm too short. Together with a partner, I then pulled the rear pocket over the stern to create a good longitudinal stretch.
I then placed a batten under from the back side of the cockpit to the stern, to serve as a guide to make the cut while sewing. Unfortunately, during the sewing proces, the batten had moved a bit off-centre (without my notice) so I had to adjust a little and got an S-shaped sewing line. But oh well, that’s the best proof it’s hand-made 🙂
I decided I wanted a clean center line without pull-holes in the fabric so I used the “welting-cord” technique. If your interested in this technique these are some useful videos:
https://youtu.be/YcvxrXVFESE (Jeff Horton from Kudzu Craft)
https://youtu.be/-bU8Q-TU4Oo (Corey Freedman from the Skinboat school)
https://youtu.be/5U0-PoDuoVA (Nick Schade from Guillemot Kayaks)
Otherwise, Brian’s technique gives excellent results, too, and it probably is a bit easier and quicker to do. I guess it’s a matter of taste.
Coating the kayak:
Before coating the kayak there was another enjoyable step: heat shrinking the fabric. First I sprayed the fabric with clean water, then ironed it two times:
Skinning the kayak with nylon has the advantage of being a very strong and durable fabric, with some heat shrinking properties. However the choice of coating materials is limited, since many compounds poorly adhere to it. Brian advices using “Corey’s goop” a two-part coating from skinboats.org. Unfortunately I was unable to obtain this (shipping to Europe would be complicated). I did a bit of research and decided to go for Coelan, which is more readily available in Europe, though very expensive (€55/750ml). It has the advantage of giving a very flexible and UV-resistant result, but it is a very toxic product to work with (always wear a good respirator!). On a next boat I would dare to experiment with cheaper coatings like Epifanes classic boat varnish, though.
I decided not to apply a dye pigment, since I like the transparant “Japanese shoji style”.
Carving the greenland paddle
After building the kayak, carving the paddle was a piece of cake. You only need two tools: a jig saw and a block plane. This task is so much more enjoyable if your block-plane is razor sharp. First, the paddle shape is cut from a western red cedar plank. Then, little by little, wood material is removed by planing. This is described clearly in Brian’s video. The result is a lightweight, beautiful paddle. Since cedar is a softwood and the tips get a lot of blows, I decided to coat the tips with a double layer of transparent epoxy to increase the durability of the paddle.
Many thanks to Brian for the excellent instructions, to fellow-SOF-builders for their wise advice and my family for their patience! It was a great journey that I can recommend to everyone!
August 9, 2020
Looks great so far! I want to see more!
September 19, 2020
Thanks Matt! I’ll soon upload some more pictures :=) It’s a fun process!
March 8, 2021
Hey Sebastian, I enjoy your work! I want to use the same materials for skining like you: ballistic nylon and coelan. I saw you shrinking the nylon with water and heat. Is the shrink-effect permanent after painting with coelan, when the boat skin become wet inside?
March 9, 2021
thanks for your kind comment. The shrink-effect is permanent, but nylon does have the property that it loosens a bit when wet or cold. I therefore think it is ideal to do the sewing of the skin and the shrinking on a wet, cool morning. You can also spray the skin a bit wet during the sewing so it is a bit more flexible. After drying and in summer months the skin is drum tight again, so no problem for me. The skin I’ve ordered from Marcin Bober from Poland. He can also give you some alternatives to Coelan for varnishing. Coelan is good, but very expensive (I used 2x750ml gloss + 1x750ml matte at €50 a piece is about €150 for the varnishing in total…).
May 1, 2021
I was wondering where you got your bending oak from. I’ve started my canoe build about a year ago but I’m having trouble finding a good bending oak supplier. Would you be so kind to tell me where you found yours? This would save me a lot of time sourcing a supplier myself (This has already cost me a lot of time). I enjoyed reading and looking at your kayak build. Good job!!!
May 2, 2021
thank you for your kind comments. I suppose you’re from Belgium too? I got my oak from my father-in-law, who had some left-overs from his oak flooring. It was air dried and had a very low moisture content. I had a lot of difficulty bending the planks without breaking. I therefore soake them in water for 1 week and used a proper metal backing belt to prevent strain on the convex side. I did got an offer from “Vercruysse hout” in Wevelgem for air-dried oak planks , but they were pretty expensive at €7/piece. I think you could also inform with companies that supply oak flooring boards (parket)? I think ash would also work find (it’s strong and steam bends well, not so rot-resistant though so you might wanna properly oil/varnish it after bending). Good luck! Seb