Building a Board

Learn how to build a Paddleboard

The Kaholo and San O’ paddleboard kits are designed for virtually anybody to build, without any significant woodworking background. They require no specialized tools, but if you have a lot of tools you may have a slight advantage. More important is not to rush it; just follow the step by step instructions and if you have a problem, contact us to assist before moving on. For most people, the Kaholo is about a 50 hour project; this will be broken up into ½ hour to 2-3 hour time periods. Some steps can be broken into sub-steps, whereas other steps must be completed as one larger step.

Following is a pictorial overview of building a wood paddleboard from a kit (example is Kaholo 14):

KAHOLO/SAN O’ CONSTRUCTION TIPS:

These tips are variations from the current Kaholo manual which I feel (after building MANY San O’ and Kaholo Paddleboard kits) are improvements in the process for either ease of assembly and/or an improved finished product.

• Clean up puzzle joints. When gluing long pieces, carefully sand the puzzle joints so that the pieces go together easily; if they hang up even a bit, you’ll end up with high/low spots on the joint that may require aggressive sanding (which will result in ugliness due to sanding through laminations).
• Chamfer hull-shear panel connection. Slightly chamfer/bevel (45 degrees) edges where shear and hull panels meet; more where they meet at a sharp angle, less where they are closer to the same plane. Doing this will make a much better, fairer chine, but will require removing, adjusting, and replacing some or most of the bulkheads, one by one.  All this is a bit more work, but makes a MUCH better board.
• Chamfer shear clamp. The lower, inside edge of the shear clamp should be chamfered at about 45 degrees (the chamfered edge will be about ½” wide). This will cut unnecessary weight, AND will make it easier to seal that underside edge when coating the interior.
• After wired, do NOT spot glue and remove the wires prior to filleting. This will leave a lot of holes to fill (the epoxy fill is harder than the wood), and it will be difficult to impossible to get fair panels. I suggest filleting over the wires, then cutting the outside wiring off (using a Crescent micro cutter, or Harbor Freight equivalent for surface flush cuts) as flush to the wood as possible, then sand to smooth rough edges.  The wires left in the wood will fill the holes (for the most part), are much easier to sand than epoxy fill spots; they look cool as you see the shiny copper edges giving it a nautical appearance.
• Thin epoxy to waterproof interior. When coating the inside for sealing, used thinned epoxy (denatured alcohol probably best); thin about 5-10%. If you research this people will discuss degrading the resin’s strength, but inside the board we are not strengthening it, but rather waterproofing it. The thinned resin will flow into every nook and cranny with ease, and getting thorough coverage is more important that thick coverage in my opinion (i.e. extra weight with inadequate waterproofing).
• Limit filleting of interior. When filleting the interior, it is not necessary to fillet fully around every bulkhead. I recommend doing the full backside of the forward bulkheads (with some tabs of fillet on the front side), and the front of all the aft bulkheads (again with tabs of fillet on the backsides); fillet fully around the two most mid bulkheads. This puts the most strength in the direction of the most force, and saves unnecessary weight. (N/A to San O’)
• Same as above, different location. Where the stringers set into the bulkheads you can fillet two opposite corners of each, and all four corners of the first and last; same reason as above. (N/A to San O’)
• Stringer locations. This is purely optional, but to optimize strength I often move the two side stringers forward and tie them into the next forward bulkhead (maybe even slightly bending them toward center).  You can notch the bulkhead about ½” deep to accommodate that connection.  I will then slide the center stringer aft so that it barely extends beyond the #3 bulkhead; this covers more of the gap between the last and second to last bulkheads; I often extend that center stringer to tie into the furthest aft bulkhead.  This was more important when the Kaholo decks were 3mm instead of 4mm as they are currently (in fact, I used to add an extruded or expanded polystyrene bulkhead between the #10 and #11 bulkheads in the K14, but this isn’t necessary unless you’re using a thinner deck, or doing it with a strip deck).
• Don’t wire stringers down to bulkheads. Instead of wiring the stringers down to the bulkheads, make sure that each notch is just adequate to keep the stringer right at (or even very slightly below) the top of the bulkheads. After resin coating each stringer, set the stringer into the notch, do the filleting at each connection (as already described), then place wax paper or plastic/poly across all connections over each bulkhead, then a piece of scrap 1×3 or 1×4 across the top making sure it covers all three stringer/bulkhead connections, and finally add a few pounds of weight on each which will push the stringer into a perfect flush position on the bulkhead.  You will not need to do this on all bulkheads, but maybe every other one or so; it will be obvious where the need is!
• Nose block fit. If the nose block that comes with your kit doesn’t seem to be a really good fit, or it is very heavy wood, I recommend custom making your own; I do this every time! I use a light weight piece of pine or redwood, and install it proud to the shear panels so that I grind/sand it down flush, typically thinning it to about ½” – 5/8” thick; plenty strong and less weight. NOTE: The nose block, any tail overlay (which is needed for structural reasons), and handle reinforcement must be installed before deck mounting.
• Interior reinforcement for rigging* (also see “Carry Handle” below). Most people will want to add bungee cords for on-deck storage.  These can be mounted to the rail, into the shear clamp, HOWEVER, you’ll have a better mount if you glue 3” tabs of leftover shear clamp material (4 of them) to the inside of the shear clamps so that the bungee mounts are on the flat of the deck. I would recommend on both the K12-6 & K14 just in front of the #s 3 & 4 bulkheads (your choice of location however), and just behind the #s 3 & 4 bulkheads on the Nui. NOTE: Typically, an added deckplate hatch (which I highly recommend installing) would be located between the #s 2 & 3 bulkheads on the K12-6 & K14; between #s 1 & 2 on the Nui.
• Leveling the interior grid. Prior to deck mounting, you must ‘level the grid.’ The best way to do this is to plane (block plane by hand, or hand-held power plane) the high edges of the shear clamps, being very careful not to catch and take pieces out of the bulkheads. For final leveling I recommend cutting a 6X24” 80 grit sanding belt so that it is one long piece, then mounting it to a 2×4 to make a long sanding block. By sanding across the whole width (both straight across and diagonally) you will have a much flatter grid, hence a much better deck mount! (N/A for San O’ due to concave deck, although you may want to consider a curved sanding block, made per the concavity template in the kit.)
• Cut deck to exact fit. It is much easier to install (i.e. no flexing up of deck due to straps or wrap), and will be rounded over enough later to eliminate any irregularities!  I NEVER recommend using nails or screws for deck mounting; if you do, you will not be able to round over enough!! I also never recommend mounting the deck cut oversized!
• When glassing, I recommend let the excess glass cloth hang over the edge by at least 6-8” (more won’t hurt); when glassing the hull, you will wet out the fiberglass down the side to the start of the rail round-over, and when glassing the deck, it will be wetted out 1-2” overlapping the hull glass. It doesn’t have to be precise at all!!
• Strategic glass reinforcement. I highly recommend adding a strip of 2” wide glass tape from the tip of the nose back about 18”along the keel line, and the same glass tape centered over the rail of the board (on each side) starting between the #s 3 & 4 bulkheads (all models) to just past mid board. These reinforcements will protect the keel-line at the nose from shore hazards, on the rail glassing will help protect against errant paddles!!  These can be added as soon as the glass itself becomes tacky.
• Fin mounting (twin). After the fins are glued on (and dry) using the jig as the manual describes, you will fillet the fin bases and reinforce the fin mount with glass. TWO THINGS: I do these in one step (fillet and glass reinforce), and I DO NOT use glass tape for reinforcement.  Instead, you will cut pieces of leftover 4oz cloth in the shape and size of the fin (using the fin as a pattern, preferably before mounting), and leaving a 2-3” flange at the bottom edge.  There will be 4 pieces of cloth; both sides of each fin. First you will make a really smooth, even fillet at the base of each side of each fin.  You will then add the glass cloth to each side of each fin, wetting it out top to bottom, and out onto the flange on each side. This will reinforce the entire fin making it near bullet-proof, and will facilitate smoothing out the edges of the glass at the edge of the fin, instead of down the center.  Using glass tape will leave a substantial edge to be feathered, which is not only difficult to do well, but creates a great risk of sanding all the way through the VERY thin glass of the fin as you’re trying to feather it out.
• *Carry handle. The handle provided with the kit is not ideal for carrying your Kaholo (which is also true of nearly all production boards on the market). The problem is that it is too short to be able to adjust the fore and aft ‘trim’ of the board. However, the solution is simple: A longer handle which you can easily obtain materials for and make yourself (or, you can purchase the materials in a package or finished handle from me); this will require internal reinforcement different than prescribed in the manual! So, all you will need is a 24” piece of 1” tubular nylon webbing (REI or mail order), a 14” piece of ½” foam caulking backing (any hardware/home improvement store), and some mounting hardware (#10×1” truss head SS screws, 1” wide SS fender washers – or flat piece of SS about 2 ½” long, drilled for two screws at each end. First you will feed (push, pull, tug) the foam backing into the webbing, centering it; then fold each end of the webbing back under itself for double thickness (using small flame or hot knife you will burn stringy stuff off the ends of the webbing – after you feed foam through); then pierce two holes through the doubled part of the webbing, preferably using something hot (i.e. heated ice pick, wood burner with round tip); finally mount the handle to the board. NOTE: Before mounting the deck, you will reinforce for the handle, and it will be different from what the Kaholo manual says. On the K14 you will reinforce about 6” in front of the #6 bulkhead, and 6” behind the #7 bulkhead; for the K12-6 you can do about 4” in front of #5 and about 6” behind #6; for the Nui, it will be 10” forward of #7, and 4” EACH SIDE of #8.   YOU WILL THANK YOURSELF FOR INSTALLING THIS HANDLE EVERY TIME YOU CARRY YOUR BOARD! It facilitates carrying it suitcase style, as well as on your head!!