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Some topics of interest
The next steps:
The final coat of resin and hardener are applied to the outside of the deck and hull.
Make the rudder hinges up and then the rudder box and tiller.
Assemble the mast and shape the booms and centerboard / rudder foil blanks ( already laminated ).
Paint everything before adding the fittings, rigging, etc.
Materials used:
Timber:
I have chosen to use a hardwood called ‘Durien’ ( imported from Malaysia or Indonesia I think ), because the other timbers specified for the PDRacer are not available, at reasonable prices or quality in Perth.
‘Durien’ has a natural long reasonably straight grain with no knots in even the longest pieces
( perfect for masts, booms etc.), looks similar to ‘Meranti’, but has densities ranging from about 0.3 - 0.5. ( the lower densities are a mottled orange with a 'Balsa Wood' like interior )
I used mainly the denser pieces for structural parts ( 0.48 measured by me ), and obtained a piece of lighter density ( about 0.38 estimated ), purely by chance ( When you order the timber you don’t get a choice on density - that I know of ).
I purchased 3 lengths ( 1 x 2100mm, 1 x 2400mm, 1 x 4200mm - all 150mm x 50mm ), and 1 x 3000mm x 175mm x 50mm
I used my new ‘Triton Saw Table’ ( 50mm max. cutting depth easily portable - with detachable circular saw - included ) to cut them down to size. I had help from a friend giving instruction, and cutting the longest pieces.
The 4 pieces were cut into every size needed to make 100% of the boat ( some later modifications were made of laminated off cuts from the last of the timber ( less wastage that way ).
Marine Plywood:
I purchased 4 sheets, 1 x 6mm sheet for the bottom, 3 x 4mm sheets, 2 as per the plan for the sides, the other for some modifications, all sheets are 4 feet x 8 feet sizes ( about 2/3 of the last sheet ( for modifications ) will not be needed.
Fiberglass products:
I have used the ‘Bote-Cote’ product because of it’s versatility, you can epoxy coat needed parts, can make it a glue, and a filler, as well as use it to apply layers of fiberglass, and you don’t get a waxy buildup as it dries, that needs to be removed, before re-coating.
Materials sources in Perth, Western Australia:
Michael Storer’s Wooden Boat Plans - Plans for the Oz PDRacer.
Plans are only available by Internet - see the ‘Useful Links’ page of this Website under the heading ‘PDRacer Web Sites’-
GBI - Timber and plywood wholesalers.
27 - 33 Cleaver Terrace
Belmont 6104
Western Australia
PH: ( 08 ) 9478 0488
Cullity Timbers - Timber and plywood wholesalers ( no website ).
Unit 11 / 257 Balcatta Road
Balcatta 6021
Western Australia
PH: ( 08 ) 9344 7000
Sorensons - 1 of 2 agents For ‘Bote-Cote’ fibreglass products in WA ( no website ).
250 Ewen Street
Woodlands 6018
Western Australia
PH: ( 08 ) 9446 6159
Witworths - Discount boating equipment.
28 Oxford Close
West Leederville 6007
Western Australia
PH: ( 08 ) 9381 1442
Duck Flats Wooden Boats - ( Not local to Perth ) ready made PDRacer Sails and all materials.
25 Secker Road
Mount Barker
South Australia 5251
PH: ( 08 ) 8391 3988
Construction method:
The modern ‘epoxy’ boat building method:
I have used the modern ‘epoxy’ boat building method and pre-epoxy coated all timber and ply parts first to make it a low maintenance boat, as per Michael’s option in the plans.
For those that don’t know, the ‘epoxy’ boat building method is simply to use screws, nails etc. as temporary fixings during assembly of the various timber and plywood parts, while the epoxy glue sets.
The screws , nails etc. are then removed, and the holes filled, leaving just the glue holding everything together, which it does extremely well, as the epoxy glue is much stronger than the timber and plywood used.
The ‘Epoxy’ is made up of fiberglass resin and hardener, with a glue powder additive ( that contains micro glass particles ), that can be mixed to make both a ‘glue’ and ‘filler’ ( thickened ‘glue’ ).
The same resin and hardener used by themselves are used to coat all of the wooden parts prior to assembly ( this is optional ), and can be used with the woven glassfiber matting to apply layers of ‘fiberglass’.
Density calculation and simple tests undertaken:
Density Calculations:
To calculate the density of timber, you simply Measure the weight in grams, and calculate the volume in cubic cm, and then divide the weight by the volume .
So if you have a piece of timber weighing 480g and a size of 100cm x 5cm x 2cm, , you multiply all 3 dimensions to get volume, then divide the weight ( g ) by the volume ( cubic cm ).
This gives a weight of 480g divided by 1,000 cubic cm, which equals 0.48 ( your answer must be between 0 and 1 - 1 = the density of water ).
Other simple tests undertaken:
I conducted a simple buoyancy test of cured ‘Bote-Cote’ ‘Glue’ mixture ( 2 parts resin, 1 part hardener, 3 parts high strength ‘fillet glue powder’ ), by holding a leftover cured piece under water and watching what happened when I let go. The result: it floated to the surface very quickly, and floated about 50% submerged, definitely buoyant.
I conducted a simple buoyancy test of cured ‘Bote-Cote’ ‘Filler’ mixture ( 2 parts resin, 1 part hardener, 6 parts high strength ‘fillet glue powder’ ), by holding a leftover cured piece under water and watching what happened when I let go. The result: it floated to the surface slowly , and floated about 80% submerged, definitely buoyant.
The results of these tests lead me to believe that my PDRacer ( empty ) may even float if all buoyancy chambers were flooded ( the deck would probably be level with the water surface though ), how safe is that.
Website Links:
Hyperlinks to Materials Suppliers in Perth , and other PDRacer Websites and Plans
can be found on my ‘Useful Links’ page of this Website under the heading ‘PDRacer Web Sites’
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