Introduction: Reclaimed Timber Hollow Wood Surfboard - 9'2
Welcome to my second Instructable! This one is about using as much reclaimed timber as I could to build a big fish, a nice chunky mellow cruiser for those gentle low swell days. The sizes are 9'2" x 23" x 3".
There are a lot of pictures here to try to show the build process. Please feel free to ask any questions using the comments feature and if you like the project then please vote in the Woodworking Contest. All the timber used is reclaimed or junky offcuts.
If there is enough interest in the project then I can draw up the plans and share a PDF with you, so don't be afraid to ask!
UPDATE = finally got the plans drawn up:
(ignore the first rib at the tail end labelled x=12.5cm - this is just for fish tail position)
UPDATE 2 = following quite a few SUP related questions I have added a new SUP template! 9'2 length, nose is 19", tail is 20 7/16 and thickness 4". Centre width is close to 28" so I reckon plenty of volume for fresh water too.
You will need to figure out the butt crack but the existing butt crack template should be pretty close - its got a bit wider in the tail so expand it a bit = if it looks right then it will be!
Step 1: Go Hunt Out Your Timber!
My stepson was working on a building job renovating a 1920's beach house on the Northumberland coast and I managed to score some old roof timbers. Knot free, tight grained and dry, and over 3m in length so plenty of material for a big hollow wood board. It would be rude not to use this perfect excuse for the next reclamation project! The nail holes and metal staining will look awesome once the board is finished, and are proof of the reclaimed nature of the materials used.
I also had some 3x2 Scots pine construction timber left over from building a bathroom at home that looked pretty good too. Long lengths and knot free are really handy for hollow wood board building. All you need to do is to rip the timber up into strips about 5 or 6mm thick, and butt join the planks together using an exterior waterproof glue like Titebond 3. Masking tape works well to hold the planks together as the glue dries, and if you have access to sash cramps and some heavy weights these help to keep the boards flat. I was thinking diagonal decks too for this build. I'm lucky that I have access to a big tablesaw for this, although any timber supplier would be happy to do this for you for a small fee. Its more important you have a flat workbench or floor area for the plank glue up.
Step 2: Stick the Frame Plans to Your Plywood and Cut Out.
I used 6mm Russian birch plywood for the fishbone frame. A friend gave me the plans so it was just a case of gluing them to the plywood and using a bandsaw to cut out the spar and the ribs. The design used an inner nose and tail block. I also drilled out any excess in order to save a little weight and to let air be able to circulate inside the board. I added a notch in the spar for a threaded brass insert (Anchor Inserts do a useful sample service if you are cheeky enough to ask..) which will become the vent. I held this in place with a couple of plywood strips and more Titebond 3.
Step 3: Cut Your Bottom Deck to Shape and Glue the Frame.
I already had a clamping jig from an earlier project. Set up the bottom section to match the spar rocker, mark out for the frame position, then apply glue. I used gorilla glue here. Then position the frame and clamp in place. You can see the nose and tail blocks here too. I used some recycled science benches for the nose (teak) and ply for the tail. I had enough teak to add a strip around the fishtail too.
Step 4: Add the Chine Strip.
You can see that the notches in the ends of each rib enable a chine strip to be easily fitted - the first rail strip will glue onto this so the chine strip determines the outline profile of the board. I also cut notches in the nose and tail blocks to locate the chine strip into. Again, Gorilla Glue is good to use here as it foams up and fills any gaps. Its also really easy to clean any excess away with a chisel. Dr Schenk PU glue works just as well and can sometimes be found on ebay for a lot less than Gorilla Glue if money is tight. The PU glue cures quick on a warm day too.
Step 5: Build Up the Rails.
I used some more slices of the old roof timber here - the first rail strip is bevelled so that the next one can hook over it. It runs the full length of the board and is tapered at each end. Gorilla glue works well for these strips. Let each strip cure overnight, and then the board can be taken out of the clamping frame for a quick tidy up. You can see where I trimmed back the rail strips at the nose and tail ready for fitting the deck planks. Can you see how awesome the diagonal bottom deck looks? I will need to make the top diagonal but the other way to eliminate the board wanting to twist. You can also see how the vent works too. I also added some blocks for where the keel fins will be fitted later on.
Step 6: Deck the Top.
I use planks glued up in twos and threes for the decks. Some people like to glue up the whole top, then feather the rails to fit the deck on top in one piece. I prefer to butt the deck planks to the edge of the rail strips as I think it gives a much cleaner look. It also means you can easily position a hole on one of the planks directly over the vent hole. The diagonal planks gave me some interesting gaps to fill, so I used some more reclaimed teak and luckily scored a mahogany hand rail too, so this was ripped up and glued in. Once the glue had cured I gave her a quick sand. Looking good!
Step 7: Tidy Up and Sand to Final Shape.
A quick tidy up of the old girls butt crack and a little time with a belt sander and she is looking really tidy. time to think about the fins. I also drilled a hole for a leash plug and glued this in with a paste of epoxy resin and sawdust.
Step 8: Fin Box Install. Disaster Strikes!
I wanted to use Lokbox keels on the fish but didn't want to buy the router jig. I decided to make my own. I used a CNC router to cut out the fin box jig, which I did in two parts so I could then router out the oval shape then the T shaped channel for the finbox. then it was a case of using the jig to cut out the recesses for the finboxes and glue them in using epoxy resin and sawdust.
I had a disaster here - the jig slipped and I ended up making the oval misshaped. After all the hours spent building, the board nearly became firewood. Time to walk away from the project for the night and think of a strategy.
Step 9: Fin Box Fix and Glassing.
The internet can be a wonderful place - one of the builders on the Tree To Sea forum suggested a pinline to hide the miss cut. I used a CNC vinyl cutter to make up a couple of stickers to cover up the edge of the fin boxes. Disaster averted!
I used a single layer of 4oz fibreglass and Resin Research epoxy resin. I filled up the fin slots, leash plug and vent with some plasticene first. Then, using some tissue paper and a laser printer I printed out my logos. For this I had to glue the tissue onto some carrier paper for it to feed through the printer, then ran it through twice to get good depth of toner onto the tissue. I laid the glass over the board and trimmed it to size - you need a couple of inches hanging over the rails, and also some relief cuts to help the glass conform to the butt crack and nose profile. Then add an apron of 50mm masking tape around the board to prevent any drips staining the top. It also gives you a guide where to trim the fibreglass after it has gelled (but before fully set). I mixed up the resin and squeegeed the logos in place first, then laid the glass over and squeegeed that in place. Once the surface has become "toffee-like" in other words nearly solid, get a craft knife and trim away the excess fibreglass. Repeat for the top, making sure the fibreglass overlaps along the rails. Gloss the board with a fill coat of more resin and leave to cure
Step 10: Final Sand.
I prefer a sanded finish on a wooden board - super glossy can make a wood board look like plastic. Sand all over using #120 grit right the way up to #1500. Open out the leash plug, vent and finboxes using a dremel and we are done!
Step 11: Hit the Beach!
Wax up and away you go!
Now.. Who's for 3D Printed keel fins?