Thursday, 2 July 2015

Cast Resin Elliptical Fins

Namaste Fin Fondlers and welcome to this instalment of making surfboard fins using epoxy casting resin. You may have noticed that things have been a bit on the quiet side on my blog. The rumours have been flying around and it has absolutely nothing to do with my lack of activity on the surfboard building front or my new interest in gerbil farming. I have been busily beavering away in the Ashram working on some new and exciting fin creations, in wood and also resin. I have also been researching into the amazing hydrodynamic properties of elliptical fins and applying this new found knowledge to fin design. I've managed to create an elliptical 9" long board fin using CNC machined marine ply and the results have been fantastic. But more of that in a future post. In the meantime, put on the kettle, make yourself a nice hot cuppa char, sit back and enjoy.

The first step involves designing the fin in CAD (Computer Aided Design) software. I've been using FreeCAD which is a free open source package. It's taken a bit of time to learn the ins and outs of the software but I've managed to teach myself everything I need to know to put together a fin design. This particular fin design uses an elliptical plan shape (think Spitfire aircraft wing) and a NACA0012 symmetrical foil which is a high lift, low drag, and low stall foil. Perfect for a surfboard fin. Once the fin is designed I super-impose it over a mould block to form the mould blank.

The mould design is then imported in CAM (Computer Aided Manufacture) software. This is where the tool paths are created. These tool paths are a set of numbered coordinates that the CNC machine will use to cut the mould out of a timber block.

 Now the fun bit. Letting the machine do its thing. Cutting the mould blank out of high quality (Furniture grade) pine. This takes about 3 - 4 hours. It's high precision stuff accurate to 0.001 mm. A mould block is machined for each side of the fin.

The completed mould block sanded with 600 grit sand paper, and finished with a polyurethane varnish.

Some timber sides are screwed in place to hold in the silicon rubber.

 The silicon rubber poured and waiting to cure. This is done for both sides of the fin.

The completed silicon moulds ready to be clamped together. 

 Ready for the casting resin.

Mixing up the casting resin with a little translucent black colour. This is a fit for purpose epoxy casting resin with excellent mechanical properties and a low viscosity for easy pouring.

Pouring the resin.

I leave the resin to cure overnight. 

 Splitting the mould. 

And  presto! As my old Dad would say "It's just like a bought one."

 Ready for some light sanding around the edges. 

I made a set of three fins (thruster prototype) for my mate Paul who is in the process of testing them for me. I'll keep you posted and provide a ride report.

Wednesday, 3 June 2015

The 7th Annual Wooden Surfboard Day 2015

Sunday the 2nd of August is set down as the date for this year's Wooden Surfboard Day to be held in the park at Currumbin as in the past years.

We look forward to meeting other budding wooden board builders and the projects that they have been working on through the year. Each year peoples experience grows and the level of skills and finish of boards is a testament to the long hours and effort being put in.

So if you are working on a project at the moment or thinking of starting one, now you have a reason to get started or stuck in to finishing it for August. Please feel free to send pics and details of any boards you are building to share with others to wet their appetite.

As you now know it is a gathering of like minded people who enjoy being challenged by spending countless hours in the shed building wooden boards. A great time to meet others with the same passion and to see what they have been up to.

If you don't build boards but want to find out more you could not be in a better place to ask all the questions you want. There are many ways to build a wooden board and they will be on display on the day.

So bring your boards and go for a surf. The Alley in winter is often at it's best for a slide across the banks on a wooden board. And there is nothing better that being on one you built yourself.

Looking forward to catching up with old faces and welcoming new ones.

For any more info contact:

Sunday, 15 March 2015

Wooden Board Repair

Namaste Splinter Merchants. Well it's a sad day when your favourite woody takes a hit for the team and has to sit it out on the bench for a while. Unfortunately, a few weeks ago, Mike thought it would be a great idea to test out his new Hotdogger in some dumpy shore break. Since he's been surfing his new woody he's had delusions that he's Michael Peterson and he's been pushing the board to it's limits. So far it's held up well but one thing led to another and he ended up pile driving his board into a sand bar. Just to give you some perspective of the forces involved, Mike is pushing 110kg which is about 250lbs in old school measurements. The result was a smashed nose block and some spilts in the deck, hull and rails. Anyway, we put the Hotdogger in for some surgery and managed to get it back on the paddock with a little help from Dr. Epoxy. Here's a few snaps for your viewing pleasure.

Friday, 20 February 2015

Hollow Wooden Surfboard Classes

For those of you who are thinking about building a wooden surfboard but don't know where to start or don't have the tools or workshop space, Stuart Bywater is offering instructor led wooden surfboard building classes at his workshop in Brisbane. Stuart is an artisan furniture maker and wooden surfboard builder with many years of experience in the woodworking trade.

Having a skilled and experienced wooden surf board builder guide you through your first build is a big help and it can save you hours of frustration, and costly mistakes.

Details of class times are available on Stuart's web site.

Sturat Bywater Wooden Surfboard Classes

Sunday, 11 January 2015

Wally's 9'1" Longboard

Namaste readers. My mate Wally has been spending time during his holidays working on his latest woody, a nine-one longboard. Wally is an industrial design teacher and spends his days showing his students how to build wooden surfboards (what a job!) but he had been neglecting his own wooden board project until recently. So here are a few snaps and some words about his latest passion. Take it away Wally.

It's been more than 12 months since I got the templates for a 6'2" Fish and a 9'1" Mal. Finally I have something to show for it. I worked with my son Peter on and off over the last 3 days. He is a pretty sharp guy and I appreciated his input. We learnt so much and have ideas to improve the next one.

Some Notes:-

The holes in the centre stringer and ribs were too large (straight from AKU and HBTM). While making the board lighter, the frame is much weaker so I will probably use circles next time and cut the drainage grooves on the laser or CNC Router. Pete will give the board a good workout to test it out and see how strong it is.

We glued the bottom skin on before the deck making it difficult to make and line up the drainage channels.

After watching Zac and Toby struggle with putting the rails on their boards I was determined to come up with a better clamping method that was quick and foolproof for the students, minimising gaps. It worked really well. Next time I will use an additional 5 clamps to ensure no gaps. We put 3 rail strips on both sides of the board in the first clamping and 2 on each side in the second.

I chose not to do any steam bending to speed things up, hence the decorative nose and tail.

I have got to say its a real buzz to see the top skins and rails go on.

We didn't glass the inside of the board because we missed this step when we glued on the first skin.

I will pay more attention to positioning and supporting the drainage system and the pressure release areas on my next board.

Pete has taken the board home to finish off will have final pics soon.

The comment repeated continually by Pete during the whole process "this is awesome".

Well Wally and I can't wait to see the photos of the finished product. There's nothing like a wooden board project to bring a father and son together. Keep up the great work.

The rocker table and clamping system.Gluing on the bottom skin.

Applying some thickened epoxy for the top skin. 

Gluing down the top skin.

A close up of the rocker table clamping system.

 The rails ready for gluing.

 The rail clamping system. The rails for both sides are glued at the same time to save time.

 A close up of the rail clamping system.

 Clamping on the rails using sash clamps.

 Ready for the nose block.

Nose blocks getting glued on.

More to come...

Tuesday, 18 November 2014

Paulownia Timber Supplies

For those of you looking for Australian plantation grown paulownia timber for your next wooden surfboard or marine project, Stuart Bywater of Bywater Designed is now supplying quality grade paulownia.

Stuart has a range of precut board sizes and can supply custom sizes to suit your needs. No order is too big or too small with delivery to anywhere in Australia.

A range of rough sawn and dressed Paulownia boards are available.

Paulownia Lengths of 2.4 or 3 meters

200 * 8 rough sawn

200 * 6 dressed 2 faces

190 * 6 Dressed 2 faces

Panels made to order

570 * 5, 4 or 3mm

600 * 5, 4 or 3 mm

For pricing go to

Call 0414 283 818

For more information contact Stuart at

Building a Foam Core Wooden Surfboard - Mike's 8' Hotdogger

Max kofler josh kofler

Namaste Hot Doggers and welcome to my latest wooden surfboard project, an eight foot woody for my mate Mike. Mike was keen to add a wooden board to his quiver and approached me to see if I could design and build one for him. Many years ago, back in the seventies, when a Brazilian was someone who played soccer and armpit hair, Chiko Rolls and Sandman panel vans were all the rage, Mike was a young grommet living on the Gold Coast. He was given a board as a birthday present by his then boss who worked next door to a local shaper. The board was called a "Hotdogger" and shaped by Ken Adler of San Juan Surfboards fame. It was essentially an egg shaped board and it went like the clappers but unfortunately Mike surfed it to death and it is no more. It was a fairly unique board for its time and Mike used to cop a bit of flack over it from his mates. It was affectionately referred to as Mum's Ironing Board (MIB).

Being a sentimental type of chap Mike was keen to relive the glory days of his surfing past so we set about designing and building a replica board based on his beloved Hotdogger. In his youth, Mike was a 6'5" streak of duck shit but since then he's put on a few kilos so we beefed up the volume of the board to make it a touch more floaty than the original.

Here's some photos for your viewing pleasure.

The outline and rocker is based on mathematical ellipses. I used a graphing application to plot the shapes and then imported them into AKU Shaper as image boards.

Gluing on the inside rail bands. I used a custom made Luthier's iron to heat and bend the paulownia strips.

My custom made Luthier's iron.

The inside rail bands trimmed up and ready for the top and bottom skins.

The top and bottom skins. Sanded, taped and ready for gluing to the blank.

The polyurethane glue is applied to the blank with a squeegee.

The skins are taped in place.

...and the board is slipped into the vacuum bag.

2 - 3 hours later after the glue has dried and all trimmed up.

The tail is trimmed ready for the tail block.

The nose is trimmed for the nose block.

Some spiritual artwork.

The right side rail bands are glued on, three at a time.

After 2 - 3 hours the board is removed from the rail jig.

All trimmed up and ready for the opposite side.

The left hand side rails being glued on.

Trimming the rails with a  palm plane and spoke shave.

The nose.

The tail.

Gluing on the tail block.

...and the nose block.

Ready to have the rails shaped.

The rails are shaped and sanded and the board is ready for its first coat of epoxy resin.

The nose block.

The tail block.

Taping up the bottom before applying the epoxy to the deck.

Weapons of choice.

Applying the epoxy.

Using a squeegee to spread out the epoxy. No need to be too precise as the roller will help get an even application of resin over the board.

A brush over with a foam brush removes any bubbles.

Now to the bottom of the board.

Cutting the fin slot with a custom made jig and trimmer.

Drilling the leash plug hole.

The leash plug hole ready for the plug.

 Gluing in the centre fin box with thickened (pigmented) epoxy resin. The ice block sticks (hot glued to the fin box) help to align the box perpendicular to the bottom of the board.

Gluing in the leash plug.

 A final coast of resin all over and a wet rub with P240, P360 and P600 grit wet and dry sand paper.

 I pyro pen the board's dimensions along the stringer.

 Some sound advice.

The board weighs in at 6.6kg

 In communion with nature.

Another happy customer. He just can't wait to get his Hotdogger wet.

Ride Report March 2015 (by Mike)

"I love the way this boards feels. It's loose and picks up speed in turns. I've only surfed it in small waves so far. I've got back into surfing recently after a 20 year hiatus but couldn't really get the hang of surfng a long board. This one is 8' but I can surf it like the single fins I used to ride in the 70's."

                                            Mike surfing the Hotdogger at Currimundi.