A few years back I purchased 10 x 6’6" lengths of 4"x2" paulownia in order to build a hollow wooden shortboard - I had no idea how much I’d need. It turned out I had enough remaining to build a longboard (and there’s still plenty for another shortboard too).
This is the tale of the longboard.
Unfortunately, I didn’t plan ahead and so don’t have photos for each of the stages. In fact, the only plan I did have was that I wanted something around 9’8", fairly wide, nice and thick, soft rails, fairly weighty, and with a flatish rocker.
I started by ripping the 4"x2"s down using the bandsaw - 2"x3/8" - and stuck them together to make the bottom skin (I used Selleys Aquadhere Exterior throughout). To get the desired length I had to glue pieces end to end. I started by gluing two of the 6’6" pieces together along the long lengths but offset to create a 9’9" plank - four inches wide where they overlapped and two inches wide at either end. I then stuck two shorter pieces in ‘the gaps’ at either end to create one plank - 9’10" x 4".
I kept adding a plank at a time, staggering the joins, until I had a bottom skin. When gluing the first couple of pieces I clamped them to a straight edge as they weren’t particularly straight along their lengths. They also needed a bit of work to ensure they were a uniform width.
For the ribs I shaped the bottom profile of each, leaving the tops flat, from lengths of the 2"x3/8" - estimating how thick the board would be at each point. Spaced about 6" apart I worked from the middle, which I wanted to be fairly flat side to side, to either end, shaping and gluing each rib to the bottom skin as I went. Moving to the nose I gave each rib a more pronounced concave. Moving to the tail I gave each rib more of a vee. I used other boards as references at each stage - either mine, buddys’, random people’s at the beach, or surf shops’.
Up until that point I’d made no effort to introduce a rocker. The reason being: the project was too long for my shed and I hadn’t determined what I was going to do for a rocker table. I ended up building one on the deck - basically a ladder frame of 4"x2"s with the cross members routed and wedged to create the rocker. I used another surfboard to give me a starting point and adjusted from there - I wanted a flatter rocker in this instance.
I had the side-to-side profile already glued in so wedges were required to get the vee to sit flat. It was at this point I realised, gluing in a stringer was going to be a bit of a palaver. I didn’t want to cut too far into the ribs as they were under a fair bit of tension/compression holding the vee and concave. Anyway, I notched out as much as I dared and glued a continuous 7/16"x7/16" length, nose to tail, to the top of each rib. This didn’t quite hold the rocker so I ended up blocking in the gap between each rib. That took ages, but did the trick.
For the rails I glued lengths of 7/16"x7/8", bent to conform to the shape and rocker, of the bottom skin. It was then a case of gluing on the top planks. I did them one at a time, starting from the middle, as I hadn’t really decided upon the dome of the deck - the ribs were still flat across the top. I’d glue a plank, joining end-to-end on a rib where necessary, and then profile the next bit towards the rail.
I was too impatient to wait until it was all glued up to start the final shaping, so I sort of planed, trimmed, and sanded as I went. But once it was all together I could go for it properly. One layer of 4oz top and bottom epoxied.
The fin I’d made a year previously. Paulownia, two layers @ 5/32" laminated to two layers of 6oz cloth up the middle - to ensure it stayed true during shaping. I think I then did three layers of six ounce once shaped. I routed a channel into the board and used epoxy to glue the fin in - minimising the required roving.
