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Exploder performance shortboard SUP fishbone framework kit

“Tunnel 13” Redwood Pin Lines for Hollow Paddle and Surfboards

“Tunnel 13” redwood pin lines

I was telling the story of the redwood pin lines material in the boards I build and my brother-in-law said, “Bro, you need to tell that story!”  So, here goes.  It’s really a story about the part of Oregon I live in and the railroad tunnels that connect Southern Oregon to Northern California.  The original railroad line north in California and the railroad south in Oregon meet at the top of the Siskiyou Mountains near where Interstate 5 crosses over the mountains.  The line was completed in the mid 1880’s and “Tunnel 13” is the one at the top of the pass.  As the story goes, the shoring timbers for the tunnels were enormous 80′ long clear, vertical grain redwood timbers that were cut in Humboldt County in Northern California in the the early 1880’s.  From that point the timbers were put on a steamship and shipped to Portland, Oregon and were then loaded on flatcars and sent south to the top of the Siskiyou grade where they were used to shore up the various tunnels, including “Tunnel 13”.  So now the story gets really interesting.  For approximately 40 years following the completion of the rail line, everything went fine at “Tunnel 13”.  Then, in 1923, the three DeAutremont brother attempted to rob the train by stopping it at the mouth of “Tunnel 13” where they proceeded to blow up the mail car killing the mail clerk.  The brothers also shot and killed both the conductor and engineer.  The subsequent manhunt lasted four years and eventually all were caught and imprisoned. The attempted robbery was the last train “robbery” in North America.

In the late 1990’s the railroad abandoned the rail line over the Siskiyou Mountains since the tunnels were designed for older and narrower trains.  When the trains stopped going through the tunnel the tunnel became a nice dry place for homeless people to live in and the homeless, with their campfires, caught the shoring timbers on fire.  A few years later the railroad decided to rebuild the tunnel to wider specs for modern trains and all of the partially burned timbers were salvaged.  At the time I was building cabinets for a new house project and the owner of the project knew the salvage contractor for the tunnel shoring timbers and we ended up building an outdoor kitchen out of “Tunnel 13” redwood.  When the house with the outdoor kitchen made from “Tunnel 13” redwood was sold I was asked if I wanted all of the leftovers and well, that’s how my prototype hollow paddle and surfboards ended up having “Tunnel 13” redwood pin lines in them.Umqua race SUP fishbone framework kit

Rocker Tabs for Building HWS

Using Rocker Tabs for Building in the Rocker Profile



paddleboard fishbone framing kit




If you have ever built a hollow wood standup paddleboard (SUP) or hollow wood surfboard you have probably built it using some variation of a rocker table.  When I started building hollow wood boards I did as well.  I built my first boards that way because that’s the way everyone else was building.  But there is a simpler way of building these hollow wood boards without building this single purpose adjustable table.  The CLEARWOOD team has developed a rocker tab system that allows the frame to be assembled on a flat work surface instead of the adjustable rocker table.  The rocker tabs are designed into the bottom to the frames and are referenced off of a flat baseline which is part of the layout created when designing the board.  The tabs are cut off and sanded flush when the board is flipped over during the building process.

If you are a builder that does your own design work you can easily design these tabs into your framework during the design process.  The addition of the rocker tabs will consume a bit more plywood but not substantially more and the simplified setup for establishing a true rocker profile makes it well worth the additional effort. I cut my frame kits out with a cnc router but I am also starting to see builders that hand cut their parts starting to experiment with the rocker tab solution to creating a consistent rocker profile.


Standup Paddle Board Fins

Standup Paddleboard Fins


I’ve been paddling my set of  Black Project standup paddleboard fins on my 12′ 6″ and 14′ flatwater hollow wood paddleboards for a couple of months now and have a pretty solid feel for the performance value this set of fins contributes to my paddling.  These are highly refined fins that address all the components necessary to provide uncompromising performance for those wanting to get the most out of their paddling whether racing or touring.  The super refined foil on these fins is based on the extensive experience of Black Project founder, Chris Freeman and his team riders who has been involved with windsurfing and paddleboarding for many years and have developed Black Project fins based on the need for speed and performance.  In my opinion, these fins leave nothing “on the table” when it comes to maximal performance.  The primary reason I have been attracted to Black Project fins has been to really get the most out of my hollow wood standup paddleboards and also, since I’m usually one of the more senior paddlers on the course I need all the help I can muster!  What I have found over the course of dozens of sessions is that the ease with which I can maintain my target strokes per side has improved and my strokes per mile have gone down by a few percentage points on average.   I find these fins to just feel smoother through the water with less visible tail turbulence than any fin I have previously used.  For crosswind/side chop conditions the R8 Series in the 28 size has provided a combination of speed, stability and control that is really easy to feel and provides major confidence in rough conditions.   All in all, these are great fins for touring or racing if you are looking for a seriously uncompromising fin. 



Flatwater and downwind fins for sups


Text of Article for

Wood paddleboards and surfboards have a long history and they have been common in Hawaii for many centuries. The modern version of “woodies” however, is something altogether different than what ancient Hawaiians were riding. With the advent of waterproof glues and plywood which became available in the 1930’s, Tom Blake who lived in Southern California began constructing the “modern” “kookbox” type of paddleboard. These were common for several decades and used by the surf lifeguards on the beaches of Southern California.

Currently, highly refined versions of the “kookbox” can be built from scratch, plans or kits and come in many forms from surf style and flat water sup’s to straight prone paddle surfboards and builders around the world have taken up the challenge of building one or several of these craft for their personal quivers. There are forums online dedicated to this type of board construction with builders from many different countries contributing to an ongoing dialogue about all of the nuances of the building process. Some woods that can be sourced for hollow board construction will yield a finished board as light as or lighter than boards of equivalent size made of foam and fiberglass, with the added benefit that hollow wood boards can and do outlast many “boards” made of foam and plastic.


I will be honest here; building your own hollow wooden SUP is NOT a quick and easy way to get on the water. You may ask why, then, would anyone want to build a hollow wood board? The answer to that question can be stated in this way: the rewards are measured in the beauty, longevity and personal satisfaction that will come with building a wood SUP with your own hands. World-wide, there is great interest in alternative building methods for “home-made” surfboards and paddleboards. What that means to a prospective hollow wood board builder is there are many different styles of hollow wooden SUPs to choose from based on your interest in the various aspects of the sport. Additionally, hollow wood boards can be built with mostly sustainable products such as salvaged or plantation grown woods and there are now epoxy resins available which are made from non-petroleum based raw materials.

The process of building a board of this type is more about a personal journey and creative expression than it is about popping out a board that looks like everything else on the water.


paddleboard and paddle on beach

In the end, most builders don’t take on projects of this sort because it is easy. Building a hollow wood SUP can be learned by most people who truly want to learn the process but it is not a project for everyone. Certainly, previous woodworking experience helps. What I say to prospective hollow wood board builders is that if a board is “in you”, you will find a way to get it built. Most suppliers of kit components provide ongoing support during the building process, and as previously mentioned there are some great online resources for asking questions and gleaning insights into how the workflow should go. In the end, patience and commitment are the two main ingredients needed for you to finish a board and get it into the water.

A question many prospective hollow wood board builders ask is, “how long will it take?” There isn’t one answer to this question. It depends on the tools you have available, your eagerness to work on a woodworking project and the level of finished product you want to achieve. What can be said about building a hollow wood SUP is that it very well could be one of the most difficult but rewarding things you do in your life!


Randy Bogardus, Artist, Shaper and Woodworker


Closing up a Hollow Board-Tasks to Consider

Closing Up a Hollow Board-Tasks to Consider

Completing the assembly manual has taken me longer than I had planned and I am hearing from some “CLEARWOOD” board builders that are nearly ready to strip the bottom and close up the shell of the board.  So let’s go through the basics of what we need to consider before stripping the bottom and closing up the shell. 

We’ll start with the blocking that supports and reinforces the fin(s), vent and leash plug.  All three of these components should be installed on both touring/race boards and surf style boards.  All hollow boards should have all three of these blocking components installed prior to closing up the shell of your board.

 Some builders may ask why they would need a leash on a board intended for touring.  This is a fair question, but think of what would happen if you became separated from your board in really windy conditions.  Boards move quickly in the wind….likely quicker than you can swim so even though you may not use a leash every time you paddle, there will be times when using a leash is essential for your safety. 

The fin is obviously a critical part of a paddle board.  It is essential to keeping you on course and tracking straight.  The lateral loads from pressure on the fin can be quite concentrated and therefor the fin(s) needs to be securely anchored to the structure of the board.  I recommend blocking both sides of the stringer (for the center fin) from three inches forward of the tail end of the board continuously to a point 2″ forward of the forward end of the finbox..  I use 1” thick material for this blocking and make the block the full depth of the stringer.  This will lock the finbox/fin assembly solidly into the framework and skin of the board giving you plenty of material from which to route a pocket for the fin box.  For surf style boards, the position and length of the fin boxes you choose will determine the position of the blocking so you will need to plan your fin layout and finbox choices prior to “close up”.


You will notice that in the photo above that the bottom went on first and that the deck went on last.  This board was built prior to developing the “rocker tab” system.  I’m showing you this photo to illustrate the blocking layout.  This board is a surf style and was set up as a quad + one.  You can also see the vent block which was installed the full depth of the board but in this case the vent block was notched to allow for pressure relief.  This is a good example of the multiple ways there are to address any particular situation with the construction of a hollow board.  In reality my system evolves.  The main idea to keep in mind are the basic principals regarding structure, venting and sealing prior to close up.

The leash plug is another component that can be subjected to quite high loading. Blocking that is securely glued to a cross (transverse) frame and skin of the board is one of the keys to avoiding leash cup failure.  The plugs that I make and most plastic plugs made commercially are in the range of  1” – 1 ¼” in diameter.  I recommend using a block that is a minimum of 2” x 2” and is the full depth of the board at the point of placement.  The placement position can vary but in general, leash cups are installed near the tail of the board on one side or the other of the stringer.  Since this block and all the other blocks necessary on the interior of your board are installed after you flip the board and before you strip the bottom, you must mark the center of the leash cup and vent blocks PRIOR to installing the bottom strips.  The simplest way I have found to mark the center of the leash plug block and the vent screw block is to drill though the block from the bottom side all the way through to the deck of the board.  I use a 1/16” diameter bit for this hole. This hole/ “mark” on the face then becomes the pilot hole when you get to the point of drilling the pocket holes for the leash cup and vent screw body and it can’t be sanded off. 

The vent screw block set up is slightly different since the vent needs to be open on the bottom (inside of the board) in order to work as a pressure relief vent.  This vent is typically slightly less deep than the body of the vent screw is long.  There are also different lengths of vent screw body’s so you will need to measure yours to determine the depth of the block.  If the block ends up being deeper than the vent body is long, it isn’t a big problem since you will be drilling through the block from the deck side.  Just remember to not make the vent screw block the full depth of the board or it won’t be able act as a vent.

At the time you “flip” your board you will have the deck and some of the rail in place.  Before you begin the process of completing the rail strips and installing the bottom strips you will want to seal the interior that is now in place.  From this point in the process of installing strips, the pieces should be pre-sealed since there won’t be any way to seal the inside after all the strips are in place.  There are several choices of material you can use to seal the interior, from thinned epoxy to marine varnish to exterior grade acrylic polyurethane.  I apply a thinned epoxy solution to all of the interior surfaces including the framework.  The reason I use thinned epoxy is because it is compatible with the epoxy I use to glue the strips in place.  The consideration in this regard is that the gluing surfaces on the framework need to maintain “glue-ability”.  Epoxy sticks to epoxy which has penetrated the fibers of the wood but would not adhere well to marine varnish, for example.  If you are using a Titebond or polyurethane product you would not want to apply a sealer to the glue surfaces on the framework since the bonding strength would then be compromised.

My system for sealing the pieces from this point to completion is to seal the strips prior to ripping them to width.  By so doing, you will then have strips with fresh wood uncontaminated by sealer.  If you are sealing your strips with thinned epoxy and installing strips with epoxy the surface contamination of the strips is not a problem but it is important to consider your sealers and glues as a “package” that needs to be coordinated for proper adhesion.

Another item for consideration throughout the close up process is how to keep the interior of your board clean and “rattle free”.  This isn’t an issue until the point where you can no longer get the “snout” of your shop vacume hose into the board.  There is no easy solution here other than vigilance.  My first board was full of wood chips that I get reminded of every time I pick the board up….rattle, rattle, rattle!  You just have to be really careful to keep the interior clean as you approach the point on “no return” with the vac hose.

That’s about it for this session.  If anyone has further questions or needs clarification email me or call me and we’ll sort it out.


Happy Building!