Powerboat Plans

 

Complete listing of Powerboat Designs
List of Discontinued Planing Hull Designs
Powerboat Hulls explained
Horsepower v Speed guide

 

Study Plan Packages contain all the sheets #1 from the actual plans plus various construction sheet from that particular plan. All available profiles and  accommodation layouts are shown. They cover several large sheets and are intended to give you a more in-depth overview of the design in which you may be interested. Material lists for all the basic materials required to build the hull, deck and superstructure are included with all  Study Plan Packages. Most study plan packages consist of between six and twelve full size sheets.

Study Plan Packages include the accommodation layouts to scale and from these scale drawings you can sketch and customize your own layout to suit your particular needs if you feel ours is not exactly what you desire. Study plans are available for all our designs and the prices are shown below. We have shown on these pages our full range of stock plans. Our catalogue shows all these designs and is intended mainly for those who do not have internet access and for those who enjoy leafing through pages of boat plans on rainy days.

To see drawings and photographs of the design that interests you just click on the links below. See below this list for an explanation of the different types of powerboat hull shapes etc.

PAYMENT AND RECEIVING STUDY PLANS AND FULL PLAN SETS.
All plans are downloadable and we will send a link for you to do so once payment has been cleared. If you wish to receive the study plans or full plan sets on CD rather than download them we are happy to burn a set to CD and post it out to you at no extra charge.
For payment you can either : phone us with your credit card details (Visa or MasterCard) : email us with the study plan or full plan set you desire and we will send a funds request through paypal so you can pay online with your credit card : by an Australian cheques : through Western Union : direct deposit into our bank account.
Once you have bought and studied the study plan set and decided to proceed to the full plan then the amount you paid for the study plan set will be deducted off the price shown here of the full plan set.

ONE IMPORTANT NOTE. We no longer sell  planing hull shapes. All powerboat designs now for sale are of either full displacement or semi displacement hull form.

 

DESIGNS
Design Name
 
Type of plan order Hull Type
Material AU $
 
Longboat 21 Study Plans   fiberglass AU$25
  wood epoxy  
  both materials  
Full Plans & Patterns displacement fiberglass AU$290
displacement wood epoxy  
Waverunner 22 Study Plans   steel/alloy AU$25
Full Plans & Patterns semi disp steel/alloy AU$290
Waverunner 25 Study Plans   steel/alloy AU$25
Full Plans & Patterns semi disp steel/alloy AU$290
Coastworker 25 Study Plans   steel/alloy AU$25
Full Plans & Patterns displacement steel/alloy AU$300
semi disp steel/alloy AU$300
Waverunner 28 Study Plans   steel/alloy AU$25
Full Plans & Patterns semi disp steel/alloy AU$300
Trawler Yacht 29 Study Plans   fiberglass AU$25
  wood epoxy AU$25
  both materials AU$25
Full Plans & Patterns displacement fiberglass AU$300
displacement wood epoxy AU$300
Coastworker 30 Study Plans   steel/alloy AU$30
Full Plans & Patterns displacement steel/alloy AU$350
Coastworker 30 mk2 Study Plans   steel/alloy AU$30
Full Plans & Patterns semi disp steel/alloy AU$350
Trawler Yacht 30/32 Study Plans   fiberglass AU$30
Full Plans & Patterns displacement fiberglass AU$350
Waverunner 34 Study Plans   steel/alloy AU$30
Full Plans & Patterns semi disp steel/alloy AU$350
Coastworker 35/37 Study Plans   fiberglass AU$30
  steel/alloy AU$30
Full Plans & Patterns semi disp fiberglass AU$370
semi disp steel/alloy AU$370
Fine Line 1100 D Study Plans
  steel/alloy AU$30
Full Plans & Patterns
displacement steel/alloy AU$370
Waverunner 38 Study Plans   fiberglass AU$30
  steel/alloy AU$30
  both materials AU$35
Full Plans & Patterns semi disp fiberglass AU$370
semi disp steel/alloy AU$370
Power Cat 39 Study Plans   fiberglass AU$35
Full Plans & Patterns   fiberglass AU$390
PCF 36/40 Study Plans   fiberglass AU$35
  wood epoxy AU$35
  steel/alloy AU$35
  all materials AU$35
Full Plans & Patterns displacement fiberglass AU$390
displacement wood epoxy AU$390
displacement steel/alloy AU$390
Waverunner 40/42 Study Plans   fiberglass AU$35
  wood epoxy AU$35
  steel/alloy AU$35
  all materials AU$35
Full Plans & Patterns displacement fiberglass AU$390
displacement wood epoxy AU$390
displacement steel/alloy AU$390
Waverunner 44 Study Plans   fiberglass AU$35
  wood epoxy AU$35
  steel/alloy AU$35
  all materials AU$40
Full Plans & Patterns semi disp fiberglass AU$450
semi disp wood epoxy AU$450
semi disp steel/alloy AU$450
Waverunner 45 Study Plans   fiberglass AU$35
  wood epoxy AU$35
  steel/alloy AU$35
  all materials AU$40
Full Plans & Patterns semi disp fiberglass AU$450
semi disp wood epoxy AU$450
semi disp steel/alloy AU$450
Cent Spray 45 Trawler Yacht Study Plans   steel/alloy AU$35
Full Plans & Patterns displacement steel/alloy AU$450
Power Cat 46 Study Plans   fiberglass AU$35
Full Plans & Patterns   fiberglass AU$450
Trawler Yacht 45/48 Study Plans   fiberglass AU$35
Full Plans & Patterns displacement fiberglass AU$450
Waverunner 52 Study Plans   fiberglass AU$35
  steel/alloy AU$35
  both materials AU$40
Full Plans & Patterns semi disp fiberglass AU$500
semi disp steel/alloy AU$500
Waverunner 55 Study Plans   fiberglass AU$35
  steel/alloy AU$35
  both materials AU$40
Full Plans & Patterns semi disp fiberglass AU$500
semi disp steel/alloy AU$500
Trawler Yacht 56 Study Plans   steel AU$35
Full Plans & Patterns semi disp steel AU$500
Waverunner 65 Study Plans   fiberglass AU$35
  steel/alloy AU$35
  both materials AU$40
Full Plans & Patterns displacement fiberglass AU$600
displacement steel/alloy AU$600
semi disp fiberglass AU$600
semi disp steel/alloy AU$600

Where Fibreglass is mentioned as a material this means Balsa sandwich / Foam sandwich, Single skin or C-Flex. All steel plans are readily adaptable to aluminium construction unless otherwise stated. Most wood epoxy designs can be built using either moulded ply or strip plank or a combination of the two.

 

PLANING DESIGNS  (We no longer sell planing hulls. The below listed planing designs are no longer for sale but are listed here for those who already have one, or have recently acquired one, and desire information on it.)
Design Name
 
Hull Type
Material
Waverunner 20/22

Waverunner 24

Coastworker 25

Waverunner 28

Waverunner 285

Coastworker 30 mk2

Waverunner 30/33

Waverunner 342

Coastworker 35/37

Waverunner 36

Waverunner 38

Waverunner 44

Sports Fisherman 47

Waverunner 52

Waverunner 55

Waverunner 65

planing hull

planing hull

planing version only

planing version only

planing hull

planing version only

planing hull

planing hull

planing version only

planing hull

planing version only

planing version only

planing hull

planing version only

planing version only

planing version only

fiberglass

fiberglass and wood epoxy

steel/alloy

steel/alloy

fiberglass

steel/alloy

fiberglass

wood epoxy and steel/alloy

fiberglass and steel/alloy

fiberglass and wood epoxy

fiberglass and steel/alloy

fiberglass, wood epoxy and steel/alloy

fiberglass and wood epoxy

fiberglass and steel/alloy

fiberglass and steel/alloy

fiberglass and steel/alloy

 

Powerboat Hulls Explained:

HULL TYPES:
Power boat hulls are divided into three main types namely, Displacement, Semi-displacement and Planing hulls. Each hull type can have many sub types, which are closer to one or other end of the spectrum. Considering each hull configuration in detail will reveal its benefits and disadvantages, your choice will be influenced by your intended usage and the size of your wallet.

The size of your intended power boat will also be a factor in your choice of hull type; for instance if you are considering a large power boat (large is a relative term) then you will be less likely to choose a full planing hull. Large fast planing hulls require large expensive engines and use large amounts of fuel and operating costs are high. Below are the outlines of the qualities of the various types of power boat hulls.

Starting at the Displacement end of the range, these were the first to be developed and to go back to the beginning of time; the original log canoe and even the ark (as far as we know) were all displacement hulls.

HEAVY DISPLACEMENT:
These heavy displacement hulls include such craft as tugs and deep sea trawlers. If you study these boats in profile you will notice that the stern rises above waterline. The mid section of the hull is very full and the midsection is deep in the water. The chine and buttock lines will reveal the full bellied shape usually present in this type of hull. The heavy displacement hull has to be able to carry great loads and in the case of tugs, be able to get a great grip on the water in order to do its job properly. The "hull speed" of this type of vessel is generally less than that of other types. This PCF 40 is a typical full displacement Trawler type hull. This hull is also used as a working trawler.

MEDIUM DISPLACEMENT:
These hulls include most regular work boats, general fishing boats and the pleasure boats where speeds of 1.34 times the square root of the water line length (or less) are sufficient to fulfil their operating requirements. For instance let us consider a 40 ft / 12.19 M, LOA. motor cruiser with a waterline length of 36 ft / 10.97 M, the square root of the waterline is 6 so multiply this by 1.34 and you arrive at a potential speed of just over 8 knots / 14.8 km/h. This is an economical speed for this vessel taking into account power required and fuel used to drive the vessel at "hull speed". Medium displacement vessels can only exceed the 1.34 rule by adding excessive amounts of power. If you already own an engine that has more horsepower than required to fall within the 1.34 calculation, then consider building a longer hull or one that employs semi-displacement hull characteristics. In a medium displacement hull, the V at the transom is usually fairly flat with anything from 3 to 7 degrees being the norm.

Once the most economical speed is achieved, it takes a considerable amount of power to make a displacement hull go faster. When this type of hull is over driven then the stern will drag in the water and usually create a large stern and bow wave. The boat may reach such an extreme bow high, stern down angle, where water could come in over the stern and swamp the vessel.

Displacement hulls should not be driven much in excess of their "hull speed". For vessels ranging in size from 30 ft / 9.1 M to 60 ft / 18.3 M waterline length, you should consider displacement hulls only if your speed requirement is around the 6 to 11 knot mark respectively. For higher speeds consider Semi-displacement or Planing hulls.

One important factor is that Displacement and Semi-displacement hulls are generally considered better ‘Sea Boats’ and are more suitable for serious offshore cruising than the planing hull type. As with heavy displacement hulls, medium displacement hulls are not so affected by weight as the semi-displacement and planing hull types.

SEMI-DISPLACEMENT or SEMI-PLANING HULLS:
As the names suggest these hulls fit neatly in between the displacement and the planing hull types. The stern of the Semi-displacement hull is lower and designed to be always below the water. The hull can be round bilge form but is generally of the 'Hard chine' type. These hulls have less fullness than a full displacement hull. The chine line runs aft with a small curve from where it enters the water and on back to the transom. The hull sections are moderately Vee'ed

wr38-06.jpg (21204 bytes)    This Waverunner 38 is a typical semi-displacement powerboat. This version performs best at speeds between 8 and 14 knots.

The semi-displacement hull will out perform the displacement ‘Hull Speed’ rules and will accept additional power and convert it to additional speed however there are limits to this benefit. Generally speaking for vessels with 30 ft 9.1 M to 60 ft / 18.3 M waterline length, you should only consider Semi-displacement hulls if your speed requirements do not exceed 12 to 16 knots.

As you have seen with displacement hulls additional power is wasted, however with semi-displacement hulls often the extra power may be utilised to advantage. If you already have access to a certain size of engine; or you already own the engine(s), then this factor may assist you in making the decision as to which type of hull best suits your situation

As with Displacement hulls, Semi-Displacement hulls can be driven harder, but at the expense of greater fuel consumption and again the stern will tend to dig in at higher speeds. Existing semi-displacement hulls can be made to achieve extra speed with the same horsepower by adding trim tabs or planing wedges at the stern. The trim tabs and the wedges will be fixed after trials are completed to establish the best angle. In no case should you try to improve the performance of your hull in this manner without the assistance of professional advice.

If you are building a Semi-Displacement hull, you should try and keep the weight to reasonable levels. The Semi-Displacement hull is a good weight carrier but it takes additional power and fuel to get the best out of an over weight boat of this type.

Finally this is the type I would personally choose when planning to undertake extended cruising, that is cruising that regularly involves cruising distances of over 100 miles from home base.

PLANING HULLS:
The planing hull is recognised by the straight run of the chine and buttock lines from midships aft. The chine and the bottom of the hull V will generally run parallel to the waterline. The V in section will generally be constant from just aft of midships to the stem The angle between the baseline and the bottom of the V will be in the range of 12 to 20 degrees at the transom. As with other types of hulls there is a great range of planing hull variations. Usually there is a planing strake or flat at the chine and often several planing stakes on the bottom of the hull.   This steel Waverunner 44 was built in Oman as a Fisheries Patrol vessel. This is one of many examples of this design. The hull is shown here to illustrate the planing flats of the chine that are necessary to help these larger steel boats up onto a plane.

You will often hear the terms 'Deep V' or 'Moderate V'. These terms are meant to convey the amount of V at the transom and in addition to this they do express two different types of hull. A true 'Deep V' hull will have 20 to 24 degrees of V at the transom while a Moderate V hull is one with around 15 degrees of V at the transom. The area in between 16 and 19 degrees can be described either way by the particular designer or builder of the particular boat. Suffice to say that a hull with a V at the transom or 20 degrees or over can be safely classified as a deep V and in my opinion should not be described as a long distance or passage making cruising powerboat.

When deep V hulls were introduced they were touted as the last word in planing hull design. These hulls do perform well at high speeds in rough water which is one reason that they are so successful as racing powerboats. Deep V planing hulls, depending on the particular design, can be driven at speeds in excess of 50 knots, however most are designed to cruise at speeds between 30 to 35 knots. Modern computers can accurately estimate the power requirements and speed expectations of all hull types and are especially helpful in the case deciding the power needed for individual planing hulls.

Planing hulls are very popular, they make great pleasure boats if you are prepared to install sufficient power and pay the larger fuel bills. Planing hulls do not like being operated at low speeds; they throw a most unfriendly bow wave. Planing hulls are not the best of sea boats especially in severe conditions. For local and coastal cruising it is worth noting that a planing hull may allow you to get home before the bad weather arrives. If your type of cruising lends itself to the advantages of a planing and if the disadvantages including high cost of operation do not bother you, then by all means consider this type. In this case a moderate V hull is recommended. On no account select a planing hull if you intend to operate your boat in the canal systems of USA or Europe. These hulls are not suitable if your cruising area is restricted to low speed operation.

Our stance here at Fine Line Boat Design is that with the large amount of fuel and resultant pollution caused by planing hulls when compared to the displacement hull form shape is unacceptable and thus we no longer sell planing hulls.

PLANING FLATS AND STRAKES:
Almost all planing powerboat hulls are of single chine configuration and most have 'chine flats' or 'planing chines' and occasionally 'planing strakes' that assist with getting onto, and maintaining the planing attitude. It is my opinion that chine flats are desirable on all planing craft. Intermediate planing strakes may not be worthwhile on boats intended to perform at less than 30 knots. Planing chines or flats, will start with a small or no flat, at, or near the bow and the width of the flat will gradually increase, until it reaches its widest point somewhere just aft of amidships and maintains this width through to the stern. The efficiency of the 'chine flat,' may be improved by canting it downward by say 2 to 4 degrees throughout its length.

ROUND BILGE:
Hulls that are intended for passage making will most likely be of the round bilge hull form. It is possible to design a semi-displacement round bilge or round chine hull but the type is more suited to the chine hull configuration. Round bilge can be used for any displacement type hull especially those that are to be used for long distance voyaging. One area we are exploring is the design of steel radius chine power boat hulls; our ideas are at the developmental stage and I believe that this idea is worth further investigation.

POWER CATAMARANS:
These boats are becoming increasingly popular and come in a variety of hull configurations. It is possible to design displacement, semi-displacement and planing hulls to be used with the catamaran concept. Semi-displacement power catamarans offer promise as comfortable, roomy and economical cruising powerboats and we are investigating this concept and already designing boats in this configuration.

 

Horsepower Vs Speed

 

Displacement and Planing Hulls

Design Hull Type Displacement Engine H.P. Speed
knots
lb kg
  Longboat 21 Displacement 3000 1360 20 to 40 6  to 8
  Waverunner 22 Semi-Displ. 6500 3000 20 to30+ 6  to 10
  Waverunner 25 Semi-Displ. 9800 4450 33 to 75 7  to 12
  Coastworker 25 Semi-Displ. 8500 3860 100 to 130 10 to 12
  Coastworker 25 Displacement 8500 3860 50 8
  Waverunner 28 Semi-Displ. 10000 4550 33 to 120 8   to 12
  Coastworker 30 Displacement 14480 6570 65 to 100 8   to 10
  Coastworker 30 Mk II Semi-Displ. 13850 6300 85 to 180 8   to 13
  Waverunner 34 Semi-Displ. 17000 7710 50 to 150 8   to 12
  Waverunner 38 Semi-Displ. 30000 13610 120 to 185 9  to 12
  Cat 39 Power/Sailor Twin Hulled 24640 11200 2x50 to 2x180 8  to 25
  Waverunner 40/42 Displacement 28000 12727 80 to 100 8  to 10
  Waverunner 44 Semi-Displ. 44000 20000 120 to 250 10  to 14
  Waverunner 45 Semi-Displ. 46000 20865 120 to 250 10  to 15
  Custom Cat 46 Twin Hulled 34000 15420 2x80 to 2x350 12  to 24
  Waverunner 52 Semi-Displ. 58000 26310 250 to 450 10  to 14
  Waverunner 55 Semi-Displ. 57600 26130 260 to 450 10  to 15
  Waverunner 65 Semi-Displ. 81540 37000 250 to 500 10  to 16

Displacement is an AVERAGE ESTIMATED DISPLACEMENT of a amateur built vessel.

 

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