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BUILDING THE FOILS (RUDDER AND CENTREBOARD)

Building the foils is a very satisfying experience and a great result can be achieved with a few basic tools and a little patience.

The Oz PDRacer plans include full size foil templates which make it pretty easy, but if you don't have the confidence, Duck Flat Wooden Boats have a great kit which comprises the laminated boards, with router cuts to the correct profile. It's then a simple task to plane back to the cuts and end up with a perfect set of foils every time.

Of course it's not much more effort and a lot more economical to build them out of scrap material, so settle back and watch the process!

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FIRST FIND YOUR TIMBER

Here is our raw material, a heap of old window reveals, which need to be milled to the correct width then laminated. Admittedly a nice pile of western red cedar or paulownia would make lighter boards and arguably would easier to work with.

The pile on the table are ready to go. There is nothing fancy about this timber, its just finger jointed pine, but with so many laminations it will be quite stable when it's finished.

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LAMINATING THE BLANKS

All the bits are cut and laminated together. As the boards will be glass sheathed, we've just used ordinary old carpenter's waterproof "yellow" glue.

At this point you will need some clamps and a flat surface to ensure that the boards are glued up with no twist in them.

If you don't have any clamps, it's easy enough to use wedges fixed to the bench top with the glue-up laid horizontal.

We've glued the rudder and centreboard as one continuous length to save a bit of work in shaping.

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MAKE THE TEMPLATE

Print the template from the plans and glue it onto a stiff card or piece of ply.

Carefully cut it to the lines, so that you end up with two pieces exactly as shown.

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ROUGH SHAPING

Clamp the blank to a bench, and keeping a check on the template, start rough shaping.

I like to use a power planer for this stage, as it removes a lot of material quite quickly, but it's a luxury rather than a necessity.

A power planer is far too aggressive for final shaping unless it is in expert hands, and even then I'd be very cautious indeed.

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CHECKING THE SHAPE

Stop regularly and check the shape against the template.

I use chalk to mark the high spots and work on those.

With the flat centre sections in the board, it's really easy to keep flat and under control with just two clamps.

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FINE SHAPING

When the shape is starting to get close, change to a hand plane. (If you started using a hand plane, have a cup of coffee and relax, you are on the downhill run!)

It's a lovely feeling making shavings with a razor sharp plane.

Swoooosh!

Plane in long strokes, preferably the full length of the board to keep it fair.

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TWEAKING THE SHAPE

As we get closer to the final shape, the plane is set finer, and the stops are more frequent.

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SHAPE THE PROFILE

Once you are satisfied that the shape is as close as it can be, it's time to cut off the backs of the foils to the shapes set out in the plan, then carefully hand plane the new profile to match the template.

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TRIM TO LENGTH

Cut the full length board "in half". OK it's not exactly half, so double check your measurements before cutting.

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FINAL FAIRING

Final fairing is done with a longish board and sandpaper, just taking out the minor bumps and tracks left from planing.

These are very small imperfections, but time spent here is rather satisfying at the end of the job.

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GLASSING THE TIPS

Round the bottoms of the foils, and then it's time to start glassing!

Hold them upside down in some convenient position. I've used a vice, because that's easy for me, but something as simple as a bungee cord round a table top would do.

Cut some strips of glass on the bias and glass the tips, don't worry if the edges aren't stuck down, they can be cut off with a razor blade before the rest of the glass goes on.

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LAYING OUT THE GLASS

Once the epoxy on the tips has set, trim and sand any rough edges, and layout the board ready for glassing.

Note we have inserted a couple of screws in the ends of the boars so we can prop them on the floor without sticking to it.

We've also elevated the boards above the table using a couple of cleats with a masking tape surface to stop them sticking to the wet epoxy.

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FUN WITH RESIN

Wet out lightly using a squeegee. A piece of ply is perfect for this purpose. The object of the first coat is to get the glass to adhere to the board.

Too much resin at this stage will float the glass away and cause noticeable bubbles, so stay vigilant and use "just enough".

You will easily see if there's not enough as it will appear dry.

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MORE FUN WITH RESIN

Once the first coat of epoxy is still tacky, pop back with a heavier filler coat.

It's easier later if you can get a reasonable finish, but don't try too hard. If you are becoming frustrated, leave it, there's plenty of time to fix it all later!

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SANDING THE BOARDS

With a nicely filled glass mat, the surface won't be perfect so it's time to become friendly with your sander.

A random orbital is perfect for this, but 120 grit wet and dry will do if you want nice muscles.

Here the board on the right is fully sanded the one on the left has clear imperfections. Click on the pic for a better view.

Both will be sanded to a nearly perfect finish, but not so aggressively as to remove any glass.

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SANDING THE LEADING EDGE

It's not possible to machine sand the curves at the leading edge, so gently sweep over them by hand with a cork block.

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READY FOR VARNISH

Once the sanding is done, the boards should have only minor imperfections, so they'll be ready for their final coat of epoxy.

If they need more work, don't be afraid to repeat the process, and give them an extra coat.

The boards in the picture have had their final coat, and are ready for a final sand and then some varnish to protect them from the elements.

Remember epoxy is not a good inhibitor of UV and should not be used as the final finish.

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In This Section:

Building notes and additions to this section are now on a monthly schedule, so watch our "news" pages, or check our ever changing menu panel as more building pages come on line:


one minute guide
building overview
• materials
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marking out
hull assembly
hull assembly 2
hull completion
foils
spars
rigging
finishing
sails
signs and graphics
kits and supplies

 

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