BMD set's a completely new standard for strength, power and versatility. Stylishly designed to turn heads, but thoughtfully engineered for function and comfort, our boats are designed for individuals who are serious about having fun on the water.
        Designed to deliver the roominess and ride of much larger vessels, BMD compromise absolutely nothing in comfort, safety or style. For example, in regards to our power boat designs, we design deep-V hulls, plenty of seating for family and friends, lots of storage for dive gear, tackle and picnic supplies and numerous standard upgrades you won't find on any other amateur built boat in their class, providing a perfect combination of features and performance.
        By carefully focusing on the needs of our customers, BMD delivers a high level of usability, technological advancement and overall boating enjoyment.

 Safety and Design

     A gritty definition of strength would be that a structure must be able to cope with an applied force or loading without yeilding or giving way. That's fine if the load or force is predictable with a degree of accurancy. Not so fine when the sea throws unpredictable loadings on a hull structure. Therefore, no matter what the numbers show at the end of a calculation there has to be a safety factor built in that  puts the strength of a structure well abaove anything it could reasonably be asked to take.

     We do not believe in the "keep making it lighter until it breaks, then go up one" style of designing. Our boats are designed to last and serve their owners well and safely for many, many years to come. If the penalty for designing a strong and seaworthy boat is a little extra weight where it counts , then so be it. Engineering to classification standards such as ABS or Lloyds ensures this.

     However, this does not mean ugly and cumbersome, nor does it means a total sacrifice of performance. What it does mean is the correct engineering in the first place for the right loadings using APPROPRIATE TECHNOLGY.

APPROPRIATE TECHNOLGY versus HIT-TECH

     At no stage in our boat plans will any reference be made to the so called HI_TECH techniques. A pre-pregged, autoclaved post cured hull, full of carbon fibre and kelvar is great for the latest BOC boat but hardly relative to the guy down the road building under a plastic shed next to the vegetable patch. Therefore we assume the right amount of appropriate technology for each project or design. It's a good phrase isn't it..... appropriate technology.

     Put it another way, we will only use a material that is appropriate for the job. Don't worry if buzz words such as tri-axial or unidirectional roving or bias seem a bit much. All you do is buy the stuff and use it. Someone else has done the hard work of designing for you.

     The advent of saturation epoxies has brought Hi-Tech into the Appropriate-tech level opening up all sorts of options for the home builder. Again, they are chemically very complex but, as someone had done the chemistry for you, all you have to do is mix them correctly, follow the instructions and stand back. Hardly a complex process.

     Using technology appropriate for it's task is, to me, distilling it down to the simplest possible level so it is friendly and accessable to the user. For anything else....confuse yourself by reading other books.

Frankly, I feel that boatbuilding should be fun and satisfying. There are new mistakes to be made and new skills to be learned - but what else can anyone ask of life?

                                                                     AN EXAMPLE OF OUR LIQUID ENGINEERING 

                       With the best technical support: we will help you succeed!
                               All our plans come with full technical support.

@ WEB DESIGN BY BOWDIDGE MARINE DESIGNS

We will respond immediately. At the same please visit our forum site, to share ideas about our boats and thousands of pictures - see completed boats and many of the building steps done by builders like you.

Designed Boat Plans

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     Bowdidge
Marine Designs
 Boat Designs with "Reel Flare"

         We have boat plans (both yacht designs, catamaran designs and power designs) for all sizes for the amateur boat builder and Professional boatbuilder. From the 12ft Mushulu plywood stitch & glue power boat design to the Oceansky 57 strip plank composite multihull design. We design and build, plywood boats, strip plank boats and fibreglass composite boats to very modern styling for both yacht designs, multihull designs and power boat in round bilge, multi-chine or radius chine hull forms, including aluminum drift boats, aluminum landing craft, aluminum monohull boats, aluminum catamarans, aluminum special purpose boats, and aluminum RIBs

   Bowdidge Marine Designs
Performance  Boat Designs with "Flare"

So he built a test panel, stripping the panel as per our requirements followed by glassing the panel as per our lamination schedule for the PT24.
You'll note in the test that he's using a 16 kg weight. The test itself under the standard, only requires 15 kg.
The panel laminate thickness where the objects are hitting represents the outside of the hull .
In this case to pass standard requirements, the drop height need not exceed 1.4m or 4.59ft. But in the 1st video, you can see the weight was dropped from a height of 2m or 6.56ft with little effect on the panel or glass and... with no de-laminations.

In the 2nd video below, this simulates a boat doing approx 20-24 kts and hitting a submerged log, shipping container or whatever with a sharp point. In order to pass this test, the claw of the hammer must not penetrate the glass. Here once again it passes easily

Mark,
2nd set of tests done. 2.5m,3.0m, and 4m. Last 2 tests at 4m (13ft ) drop. The weight hit the board and rebounded about 5 feet back into the air-we could not find any mark or damage. We repeated at 4m and this time the weight rebounded about 7 feet up, eventually falling and finding its mark on a large flower pot. There was also a bruising mark on the board. No sign of any significant damage or breakage of the skin. Conclusion-Amazing! bomb proof. I doubt any ordinary marlin would even scratch our hide.

Regarding the claw hammer test-deepest indent was 0.42mm.
CONCLUSION:
Mark,
This really was a worthwhile exercise, not just for confidence, but also for understanding in regards to how you engineer your boats.
Thanks for you help and support.
Earl

Recently talking with Earl, who is building the Pro Tournament 24 from the Philippines, one of the concerns he had was the material that are available. So we talked about using different materials and in the end I mentioned about building his boat from Plywood, but strip planking it as per a normal strip plank hull as you would using Paulownia or Western Red Cedar. His concern though was that the plywood available is absolutely rubbish, being that it comes from China. In other words, you can drive a screw into it and basically pull it out with your hands, its that weak.
Not a problem I said, we'll engineer it differently, then let's do an impact test as per standards.

                                                                           LIQUID ENGINEERING - A MATTER OF STRENGTH
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