Before applying a thin seal coat of epoxy to any remaining exposed wood surfaces in the interior of the board and completing the strip planking process, it is necessary to install internal blocking to support the fin system, vent body, leash plug, and any tiedowns or other accessories you may decide to build into your board.
Customers that purchase a full kit from Clearwood will receive internal blocking with their shipment. If you are procuring internal blocking on your own, good options include: EPS foam, Paulownia, and Balsa.
If you are building watertight bulkheads/compartments into your board for extended touring, deck hatches must have support blocking attached to the underside of the deck.
Blocking Layout
Careful planning is the key to successful blocking layout. Once you have selected the fin system, vent body and leash plug sets for your board, identify appropriate placement and record a list of measurements that correspond accordingly.
Later, you will use these measurements to hog out material, drilling into/through your strip planking to create the openings to install your fin boxes, etc.
We recommend reviewing the resources offered by GEARBOX, including the fin setup primer and install processes.
Below is an example of the internal blocking layout for a five-fin SUP that also includes vent and leash set blocking.
Note that the depth of the vent body and leash plug are different. The leash plug block is the full thickness of the board. The vent body has a groove to allow for ventilation.
Vent Body and Leash Plug
If you have drilled locator holes for the vent body and leash plug before completing the strip planking, the process is less stressful. In the picture below you can see the small locator hole for the leash plug to the left. Try not to forget!
Regardless, as noted previously, take accurate measurements to know exactly where to drill for the vent body and leash plug - including which side is which. This is because you must stop at a specific depth for the leash plug, but you need to drill through the block for the vent body.
Start with a pilot hole to guide the use of a sharp 1 1/2" Forstner bit, if installing the Clearwood vent body and leash plug.
When gluing (epoxy) the vent body and leash plugs we recommend taping around the openings with blue painter's tape to minimize the amount of sanding of hardened adhesive that squeezes out during the installation process.
If using the Clearwood vent body and leash plug note that all wood must be coated with epoxy before installation in order to prevent leakage at some point in the future.
You will also need to find a way to hold the vent body at a fixed position while the glue sets, such that it does not drop below the deck strips. The goal is for both the vent body and leash plug to be installed slightly proud of the deck and later sanded flush.
SUP Grip
The Clearwood SUP Grip is machined from a block of lightweight Paulownia.
Installation involves gluing the grip to the interior of the board with thickened epoxy, adjacent to a frame to improve rigidity. Consider your dominant carrying arm, and layout the grip location at a position between the centerline and rail, at the fore and aft balance point.
Drill a locator hole through the deck and be sure to carefully measure for the final step of cutting into the strip planking and rounding off the edges for comfort and aesthetics.
Fin Box
Similar to the vent body and leash plug, locate where you will cut into the board using the measurements recorded prior to completion of strip planking.
The Fins Unlimited 10.5" center fin box is included in Clearwood's full kit, some designs excluded depending on your preferred fin system and configuration.
If you are using twin, thruster, quad, 2+1, etc, templates and jigs for the installation of fin boxes, please follow directions covered separately by the manufacturer.
But, if you are installing the Fins Unlimited 10.5" center fin box, we suggest building a jig. The jig is specific to your router setup and is secured to the board with face clamps.
After internal blocking is laid out and glued in place, it is time to seal the interior.
Please reach out with your questions!
