Power Boat
     Bowdidge
Marine Designs
Yacht, multihull and sailboat designs
@ WEB DESIGN BY BOWDIDGE MARINE DESIGNS

         We have boat plans (both yacht designs, catamaran designs and power designs) for all sizes. From the 12ft Mushulu Dinghy stitch & glue yacht tender to the Oceansky 57 catamaran. We design timber boats, plywood boats, strip plank boats, fibreglass composite boats, steel and aluminum boats to very modern styling for both monohull designs or multihull designs, powerboat or sailboat and in round bilge, multi-chine or radius chine hull forms.

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Mushulu 12 Builders

   Boatbuilders Testimonials

Cruise Control 5.2 Specifications & Plans List
   Boat Plans

                                    

                                   

Sheet 17 - Plan & Profile Construction sheet
Sheet 18 - Cabin lamination & Tabbing Detail
Sheet 19 - Bulkhead Nesting Detail
Sheet 20 - Cabin Nesting Detail
Sheet 21 - Cabin Panel Construction sheet
Sheet 22 - Full Size Bulkhead/Frame Templates
Sheet 23 - Full Size Bulkhead/Frame Templates
Sheet 24 - Full Size Bulkhead/Frame Templates
Sheet 26 - Electrical wiring diagram sheet
Sheet 10 - Frame Construction
Sheet 12 - Construction Sections/ Plan & Profile Detail
Sheet 13 - Construction Sections/ Plan & Profile Detail
Sheet 14 - Construction Sections/ Plan & Profile Detail
Sheet 15 - Construction Sections/ Plan & Profile Detail
Sheet 16 - Construction Sections/ Plan & Profile Detail
Builders Construction Manual
Sheet 11 - ABP/ USCG compliance construction detail
Sheet 1 - Profile & Arrangement Plan
Sheet 2 - 3-D Perspective Plan
Sheet 3 - Lines Plan
Sheet 4 - Strong Back Construction & Set-up plan
Sheet 5 - Longitudinal layout
Sheet 6 - Lamination Schedule
Sheet 7 - Plywood Hull Panel Construction
Sheet 8 - Longitudinal & CVK Construction
Sheet 9 - Hull panel nesting sheet
                                                    SPECIFICATIONS
                   Quality & Comprehensive Plans for the
                                 Amateur Home Builder
Sheet 25 - Full Size Bulkhead/Frame Templates

     The following drawings will be supplied. Back up service is also provided as needed. 
All plans provided are drawn on 2ft by 3ft sheets 
                  includes full size patterns

Sheet 1 - Profile & Arrangement Plan
Sheet 2 - 3-D Perspective Plan
Sheet 3 - Lines Plan
Sheet 4 - Strong Back Construction & Set-up plan
Sheet 5 - Lamination Schedule
Sheet 6 - Longitudinal Layout
Sheet 7 - Panel Measurements and Construction
Sheet 8 - Bulkhead Construction Detail
Sheet 9 - Australian Builders Plate Construction Detail
Sheet 10 - Construction Sections/ Plan & Profile Detail
Sheet 11 - Construction Sections/ Plan & Profile Detail
Sheet 12 - Construction Sections/ Plan & Profile Detail
Sheet 13 - Construction Sections/ Plan & Profile Detail
Sheet 14 - Construction Sections/ Plan & Profile Detail
Sheet 15 - Construction Plan & Profile Detail
Sheet 16 - Cabin Lamination & Tabbing Detail
Sheet 17 - Bulkhead Nesting sheet
Sheet 18 - Cabin Nesting sheet
Sheet 19 - Full Size Bulkhead Patterns
Sheet 20 - Full Size Bulkhead Patterns
Sheet 21 - Full Size Bulkhead Patterns
Sheet 22 - Full Size Bulkhead Patterns
Sheet 23 - Full Size Temporary Frame Patterns
Sheet 24 - Full Size Temporary Frame Patterns
Sheet 26 - Full Size Temporary Frame Patterns
Sheet 27 - Electrical wiring diagram sheet
Builders Construction Manual
                   Quality & Comprehensive Plans for the
                                 Amateur Home Builder
                                         STRIP PLANK COMPOSITE PLANS LIST
Sheet 25 - Full Size Temporary Frame Patterns
                                         PLYWOOD COMPOSITE PLANS LIST

                  The following drawings will be supplied.
             Back up service is also provided as needed. 
  All plans provided are drawn on 2ft by 3ft sheets 
               Includes full size Patterns

MUSHULU 12 SPECIFICATIONS
Length of Hull:  17ft     (3.66m)
Beam: 5ft - 6in            (1.67m)
Depth: 2ft - 4in          (.701m)
Freeboard : 1ft- 6in      (.457m) 
Transom Shaft Length: S/S (15" or 381mm)
Weight (boat only): 145 lbs (66kg)
Min Rec. HP: 15 hp
Rec. KW: 11.18 Kw
Max. HP: 20 hp
Max. KW: 14.91 Kw
Max. Main Motor Weight: 121lbs    (55kg)
Number of People (Basic): 4    (NOTE: 1 person = 1 adult or 2 children)
Max Load (Basic): 676 lbs    ( 307kg)

Design Brief:
 Overall, our main priority had to a simple open plan design, with the priority being for easy planing at low speeds, great stability whilst at rest, and  reduction in fuel consumption without compromising the strength, durability and safety of the design. Careful consideration was given to loads of storage lockers, comfortable seating throughout and a stable platform for fishing or other recreational activities without compromising safety for those on board.
    The principles on which our boats are designed are for strength, safety, seaworthiness and comfort. We will not sacrifice these in order to gain high performance. Nevertheless, our boats have a reputation as excellent performers. They are also known for their strength.

    Designed for ease of construction for the first time builder, the Mushulu 12 is light enough to be easily trailerable for adventures in distant places. But overall, it had to be simple and easy to build, without spending everything you have.

                                                                                    The Arrangement Plan
                                                                                                   Performance

Running through HullSpeed (a part of our Maxsurf ship modeling program suite), the result is a light hull built in our standard material epoxy-glass-plywood composite construction. The deadrise is 60 degrees at the cutwater, about 14 midship and 10 degrees at the transom, the Mushulu 12 has enough vee to handle choppy seas without problems and her moderate beam produces great stability and lift for planing at low speeds.

As the chine rise is very progressive, the Mushulu 12 does not have an obvious hump in its transition from displacement speeds to planing, resulting in a good moderate speed boat. Overall, the Mushulu 12 is able to maintain moderate speeds between planing and displacement without pushing a huge bow wave.

     Approx Planing Speeds Vs HP @ 60% Propeller Efficiency
Horsepower vs Speed (kts)
Speed (kts) vs Trim Angle
Please click above image to enlarge
Please click above image to enlarge
NOTE: Figures provided above are based the vessel being loaded as per a normal days outing  
                                                                            Australian Builders Plate
Click Image for More information
    All our Designs comply with the Australian Builders Plate / USCG National standards

Australian Builders Plate
The purpose of the Australian Builders Plate
The Australian Builders Plate is a national initiative that will make boating safer by providing vital information about the capacity and capability of boats. The Australian Builders Plate requires boat builders to determine boat-specific information and display it on the plate in a standard format. The information that needs to be provided includes: 

  • recommended maximum engine power rating and engine weight for outboard engines 
  • recommended maximum person capacity and maximum load
    Flotation used (basic or level)
"The Cruise Control  5.2"
"Engineered ...with style"
        For the arrangement plan, the question most asked is;
"Could we please  include a private area in regards to the toilet arrangement, not only for guests but more importantly... the opposite sex". So in this regard, we made this one of our  top prioritys with this design, using real walls and not flapping curtains to the outside world.                      
       In regards to design of the hull, the Cruise Control 5.2 incorporates a sharp high entry angle at the bow and a 20 degree deep-V hull form at the transom, delivering a smooth dry ride by displacing water away from the boat, while a wide bow flair keeps it from rolling back into the boat. Also by featuring a higher degree of deadrise at the transom, this provides added stability in rougher seas.

        Also the large chines on the Cruise Control 5.2 hull form, deflects water down and under the hull, acting as two points on which it balances. These points provide a great deal of dynamic stability for a more solid ride while also increasing lift and reducing drag for a faster more efficient running hull.
 Australian Builders Plate / USCG Compliant