Francois Vivier Morbic 12 Building Instructions

Building Morbic 12

Clinker dinghy

Customer name :

Plan number : MO12 -

© François Vivier – March 2017

7, avenue des Courtils – 44380 Pornichet - France

tél : [phone] or 33 (0)2 28 54 97 86

E-mail : [e-mail] – www.vivierboats.com

François Vivier Architecte Naval – SARL au capital de 8 000 € - Siren : 451 456 669 RCS Saint Nazaire

March 2017 Building Morbic 12 Page 2/21

1. Plan package content

1.1. The present manual

1.2. Appendices

Numb Rev Titre Date Pages

1 8 Timber list 2 October 2013 2
2 10 Plywood list 18 April 2015 11
3 5 Fittings 2 October 2013 3

1.3. Manual of “wooden boatbuilding” sheets (mainly in French)

These documents are extracts from my book on wooden boat construction, “Construction bois les techniques mod­ernes” (in French). Though only a few are presently translated, equivalent information in English is available from
other sources. For example, the websites of epoxy suppliers give comprehensive information in regard to saturation,
gluing, filleting, and sheathing. Sheet 44 is already translated and I intend to translate other ones. If you need some
technical advice, please tell me and I will answer your questions.

Numb Version Rev Titre Date Pages

05 Toutes 0 Imprégnation époxy 25 sept. 03 2
06 Toutes 0 Collages et joints congés 14 octobre 03 2
07 Toutes 0 Stratification sur bois 15 novembre 03 4
08 Toutes 0 Imprégnation et collage : solutions par temps froid 12 novembre 03 3
12 Toutes 1 Rivets à bateaux 15 novembre 03 2
15 Toutes 1 Scarf des panneaux de contreplaqué 9 novembre 03 2
16 Toutes 0 Pièces en lamellé-collé 30 décembre 03 4
22 Toutes 0 Montage de la structure sur chantier 8 avril 04 8
43 Toutes 0 Tenue provisoire des clins 6 novembre 03 1
44 Toutes 1 Liaison des bordés à clin 3 avril 04 3
51 Toutes 0 Bordé en contreplaqué cousu-stratifié 8 avril 05 4
71 Toutes 0 Bancs et planchers 7 octobre 03 1
72 Voile 1 Gouvernail à safran relevable 2 novembre 09 2
81 Voile 0 Mâts et espars ronds 17 octobre 03 3
82 Voile 0 Le gréement au tiers ou de misainier 10 octobre 03 3
91 Voile 0 Peintures et vernis 18 novembre 03 3

1.4. Plans (A3 format booklet)

Numb Version Rev Titre Date Scale

01 All 0 Hull lines (outside planking) 6 February 2008 1/15

12 All 3 Building frame 7 November 2010 1/15
21S Sloop 5 Longitudinal structure 2 October 2013 1/10
21T Balanced 6 Longitudinal structure 2 October 2013 1/10
22S Sloup 5 Transversal structure 19 September 2011 1/10
22T Balanced 7 Transversal structure 19 September 2011 1/10

25 Voile 3 Rudder 2 November 2009 1/10

31 Balanced 0 Balanced lug rig 6 February 2008 1/25

32 Sloop 1 Lug sloop rig 20 June 2008 1/25

33 Balanced 0 Battened balanced lug rig 31 October 2009 1/25

35 Balanced 0 Mast and spars balanced lug rig 6 February 2008 1/15

36 Sloop 0 Mast and spars sloop lug rig 7 August 2008 1/15

41 Sail 1 Oars 30 January 2009 1/10
S31 Sail 0 Sail mark 6 February 2008 1/1

51 All 1 Building frame dimensions 18 April 2015 1/10

52 All 0 Hull planking dimensions 20 December 2014 1/10

53 All 0 10 mm plywood parts dimensions 20 December 2014 1/10

54 All 0 Stem dimensions 20 December 2014 1/4

55 All 0 6 mm plywood parts dimensions 20 December 2014 1/10

This document is the property of François Vivier Architecte Naval. It shall not be copied, transmitted to any other person,

nor published as a whole or partly, without the written consent of the architect.

March 2017 Building Morbic 12 Page 3/21

56 All 0 Rudder dimensions 20 December 2014 1/3

57 All 0 Timber parts 13 September 16 ½ & 1/4

2. Main characteristics

2.1. Dimensions

Hull length 3.67 m
Waterline length 3.35 m
Breadth 1.55 m
Waterline breadth 1.40 m
Draught (centreboard up) 0.17 m
Draught (centreboard down) 0.78 m
Depth under sole 0.56 m
Sail area (balanced lug) 7.6 m²
Sail area (sloop lug) 9.4 m²
Sail area (battened balanced lug) 7.8 m²
Buoyancy 230 litres
Light weight (without rig) 80 kg (about)
Light weight ISO (ready to sail) 110 kg (about)

The ISO light weight refers to the boat ready to sail with rig, centreboard, rudder, oars, anchor and mooring
line. This weight will vary according to choice of plywood and timber. Thus, it is recommended to weight the
boat prior ordering the trailer.

2.2. Boat presentation

Morbic 12 was designed to be:

✔ A dinghy, able to take 1 to 3 crew, with a performing balanced lug, as the International 12 feet which has

been an Olympic class.

✔ A "sail and oar" boat, able to sail anywhere. The moderate size makes Morbic 12 an ideal boat for fre -

quent single handling but she is able to take a crew of 3 and is fitted with 2 rowing thwarts.

✔ And also a simple motor boat, with its generous transom width. A cut-out in the transom allows to fit a

short-shaft outboard motor.

The small size of Morbic 12 allows such a multi-purpose use. Being light, she may be rowed easily, despite
her generous breadth giving stability for sail and motor. Morbic 12 is:

✔ A practical boat, the flat bottom making easy hauling on the strand,

✔ A modern design, with clinker plywood, for easy construction by a first time home builder,

✔ Simple with the pivoting and removable centreboard and minimal structure items,

✔ Safe with large side buoyancy tanks,

✔ Light and so effortless,

✔ 2 rig options : standing lug (picture) or sloop lug (with a jib).

✔ And all that keeping the lovely looking of a classic boat.

2.3. Motor version

There is also a purely motor version, without a centreboard and rudder and with a large locker forward. It is
built from a separate plan package.

2.4. Building time, tools

It is difficult to give an estimate of the time of construction, so much this one varies from one builder to an ­other, according to the experience possibly gained during former constructions. The tools you have at disposal
and you are able to master influence the working time. Some boats are true works of art, others are rather of
simple and rustic style.

The cutting up of timber takes also time which could be sub-contracted. Only basic portable tools are neces ­sary: drill, screw driver, jigsaw, electric plane (especially for mast and spars), without forgetting a good quant­ity of screw clamps.

The building time is about 200 hours, using precut timber. Construction time may be doubled for a first con ­struction project and if you want a high quality finish. These times are complete, including rig, fitting and paint ­ing. To build yourself such a boat supposes that you are looking mainly for the satisfaction of a beautiful work,
without being to much worried by time constraint.

This document is the property of François Vivier Architecte Naval. It shall not be copied, transmitted to any other person,

nor published as a whole or partly, without the written consent of the architect.

March 2017 Building Morbic 12 Page 4/21

2.5. Compliance to regulations

WARNING

Morbic 12 is a boat that may capsize. Thus it is important:

to be equipped in order to withstand immersion into water,

to be prepared to right the boat,

to be always vigilant, to carry the sail appropriate for the wind and the sea state,

particularly if no external assistance is available.

Morbic 12 is designed in compliance with the requirements of the European Recreative Craft Directive
1994/25/CE amended 2003/44/CE.

It is designed to sail in the following categories:

✔ In category C, with a maximum of 2 persons on board (maximum loading 200 kg)

✔ In category D, with a maximum of 3 persons on board (maximum loading 250 kg)

The minimum crew is one person, as the boat may be right up by one person only in calm sea conditions. It is
recommended to be at least two on board when sailing in poor wind and sea conditions or away from any pos ­sible assistance.

The maximum power of the outboard motor is 3 kW.

The definition of these categories is pointed out below:

Category C (Inshore): designed for trips in coastal waters, large bays, estuaries, lakes and rivers where condi­tions up to, and including, wind force 6 and significant wave heights up to, and including, 2 m may be experi­enced.

Category D (Sheltered waters): designed for voyages in close coastal waters, small bays, lakes, rivers and
canals where conditions up to and including wind force 4 and maximum wave heights up to and including 0,3
m may be experienced.

NOTE: The significant wave height is the mean height of the highest one third of the waves, which approxim ­ately corresponds to the wave height estimated by an experienced observer. Some waves will be double this
height.

This document is the property of François Vivier Architecte Naval. It shall not be copied, transmitted to any other person,

nor published as a whole or partly, without the written consent of the architect.

March 2017 Building Morbic 12 Page 5/21

3. Right of use and general information

3.1. Right of use

The purchase of plans gives the right to build one unit, by an amateur builder. They can be sold only by the
naval architect (François Vivier) or approved partners (see my web site).

Plan package, comprising the present manual and all the attached documents listed on page 2, is the prop ­erty of the architect. Except for the needs of construction and purchasing (sail plans, material lists...), the doc ­uments may not be reproduced, transmitted to a third party, nor published entirely or partly, without written au ­thorization from the architect.

3.2. Plan number

The plan number, registered on the front page of this manual, is specific to the purchaser and must be re ­called in any correspondence with the architect or Icarai (builder and kit seller).

Please inform the architect when the boat is first launched, and of change of address or ownership while
building.

3.3. Liability of the builder

Morbic 12 was designed with care and in full compliance with the European regulations. However, each boat
is built under the whole responsibility of its builder, and sails under the whole responsibility of its crew. Both
the architect and Icarai (boats from a kit) decline any liability in regard to people, legal entities, and property
resulting from construction and/or from use of a boat built from the plans.

3.4. Respect of the weights, scantlings, materials, and buoyancy

Amateur builders should be careful to note the necessity of respecting the plans and specifications, especially
scantlings and choice of materials, so that the boat does not become too heavy. Such extra weight would
make it less seaworthy, more difficult to launch and retrieve, and would involve a risk of overloading the road
trailer. Conversely, it is strongly dis-advised to reduce scantlings or to use materials of lower quality. Respect ­ing the specifications concerning volumes of buoyancy is an essential condition for compliance with EC regu ­lations.

3.5. E-mail assistance

If you encounter difficulties during construction, or if you have suggestions to make, please feel free to contact
the architect (preferably by e-mail or phone). Specify the number and the date of the plan (see front page).
We will answer your questions and, if necessary, update the plans to benefit other builders.

François Vivier Architecte Naval

7, avenue des Courtils – 44380 Pornichet - France

tél : [phone]

e-mail : [e-mail]

www.vivierboats.com

Note: I am always happy to receive pictures and news about the boats I have drawn !

3.6. Supplies, kit

Materials and fittings needed for construction, in particular those specific to the boat, can be sourced from my
partners (see my web site): marine plywood (panels or NC cut parts), sawn timber, centreboard, fittings, sails,
outboard motor, trailer.

I have observed that to buy a kit allows the amateur builder to avoid bad surprises, un-compliant purchases,
high delivery costs and generally is a cheaper and easier way that to try to source all different materials and
equipments.

This document is the property of François Vivier Architecte Naval. It shall not be copied, transmitted to any other person,

nor published as a whole or partly, without the written consent of the architect.

March 2017 Building Morbic 12 Page 6/21

4. Plywood Kit and full size patterns

New (April 2015): the Morbic 12 plan package comes now with dimensioned drawing. Therefore, kit or full size
patterns are optional.

4.1. NC cut plywood kit

The kit includes all the plywood parts necessary to the construction precut on numerically controlled machine.
The majority of parts are at final dimension or require only little fit. Refer to the appendix 2 which gives the
nesting plans of the parts in all panels. The planking strakes are assembled by “puzzle joint”, as shown on the
following sketch. You have to glue them together and get a plank ready to be placed on board with only ends
adjustments:

Puzzle joints require to be glass-epoxy sheathed inside, at least in areas which may be in contact with trailer
rollers or supports during launching and recovering.

The kit offers up the following advantages:

✔ Reduction of the construction time: you will save the time of marking and cutting many parts within many

plywood panels.

✔ Reduction of the need for space to scarf and cut out the panels.

✔ Reduction of the risk of construction error and improvement of the assembly accuracy.

Kit is to be ordered to boat-builder Icarai (see page 5) in France of other representatives abroad. If you buy
the kit, you do not have to order the polyester patterns.

The construction described in the following pages is based on the assumption you are working from
full size patterns. If you have the plywood kit, some task are deleted.

4.2. Full size patterns on polyester film

These patterns give the marking of moulds, bulkheads, centreboard case, transoms, planking, rudder...
Bevels are drawn. Position of battens and various pieces to be fixed on the bulkhead faces are also marked.

The support is a polyester film (also said mylar), very resistant to tearing and not subject to humidity vari­ations. Marking are to be transferred to the plywood sheets.

For that purpose, you may use a screwdriver grinded to form a spike. With a hammer, the wood is marked
through the film. You may also use carbon paper spread between film and plywood. An other very efficient
method is to use a tracing wheel as used by dressmakers :

Polyester patterns are delivered in a resistant tube and are to be ordered from François Vivier Architecte
Naval SARL according to current price list.

This document is the property of François Vivier Architecte Naval. It shall not be copied, transmitted to any other person,

nor published as a whole or partly, without the written consent of the architect.

March 2017 Building Morbic 12 Page 7/21

5. Summary of the construction process

Before starting the construction, the general process of which is presented in the following pages, it is import ­ant to read the whole manual and plans for a good overall comprehension. That remains true at all stages. A
good preparation will avoid errors, sometimes not easily retrievable, and will save time.

The general process is as follows:

✔ Cut-out of the moulds and main girder from chipboard or MDF panels,
✔ Assemble the transom, the stem, the false stem, all made of several layers,
✔ Set up all elements on the building frame,
✔ Lay down clinker planking,
✔ Fit the false stem, make epoxy fillets on the outside hull,
✔ Turn over,
✔ Fit the gunwales, rub-rails, seat risers, buoyancy tanks,
✔ Sheath the sole and garboards,
✔ Fit the centreboard case, mast step and mast partner, foot rests,
✔ Turn over for outside hull finishing works,
✔ Sheath the sole and garboards,
✔ Fit the skeg
✔ Paint the hull
✔ Turn over again for inside finishing works,
✔ Painting and varnishing
✔ Fittings

The following tasks may be done at any moment and scheduled according to your own space and weather
constraints:

✔ Centreboard,
✔ Rudder,
✔ Mast and spars,
✔ Oars...

This document is the property of François Vivier Architecte Naval. It shall not be copied, transmitted to any other person,

nor published as a whole or partly, without the written consent of the architect.

March 2017 Building Morbic 12 Page 8/21

6. Chronological description of construction

6.1. Building frame

Patterns

Appendix 2

Plan 12

Sheet 22

The building frame is based on a stiff main girder (250 X 350 mm), made of chipboard or MDF
panels. MDF is easier to work out and is chosen for NC cutting.

The fore face of the main girder will be used as support for the fore bulkhead of the boat. There ­fore, it has to be perfectly perpendicular to the other faces of the girder.

Doublers are screwed into the girder sides in order to make slots for the proper positioning of
girder supports and station moulds (see plan 12).

The main girder is supported by chipboard/MDF transverse parts. If preferred to ease work, the
main girder may be raised using saw horses or any other available means.

Then set down all six station moulds and check they are perfectly aligned and spaced. 3 of these
moulds are in fact bulkhead supports. Only bulkheads are part of the finished boat. Holes (6 mm
diameter) are drawn on the patterns (and already cut-out in the kit) to allow quick and good posi­tioning of these bulkheads.

Look carefully at plan 12 to place properly the bulkheads (for or aft of station moulds).

Before bolting the bulkheads, protect the station moulds with plastic film to avoid gluing the hull
planks on these moulds. Notice that moulds are voluntarily recessed from the bulkhead outline in
the overlapping area.

6.2. Cut-out and assembly of structural parts

Patterns

Appendix 2
Appendix 1

Plan 12

Sheet 22

All parts are cut-out using the patterns. Several parts need to be pre-assembled:

✔ The transom is made of 2 layers. The inner layer is cut-out with 2 mortices in order to fit into

ends of side seats longitudinal bulkheads. Glue both layer using bolts into the alignment holes
to avoid slipping of parts when glue is curing. Afterwards, remove bolts and fill in the holes
with epoxy putty. Bolts may also be replaced by screws which may be kept in place. Upper
edges of both layers of transom are aligned. Other edges are slightly shifted. This allows to
get the proper bevel as follows:

Gluing of transom and centreboard (background)

✔ The stem is made of 3 layers of 10 mm plywood. The centreline layer ensure a link with bulk -

head 5. An additional layer of 6 mm ply is glued over both sides to make an apron, increasing
the gluing area of the hull planking over stem bevels. As for the transom, use bolts to keep the
alignment of parts when glue is curing. The following sketch show how to get the stem bevel:

This document is the property of François Vivier Architecte Naval. It shall not be copied, transmitted to any other person,

nor published as a whole or partly, without the written consent of the architect.

March 2017 Building Morbic 12 Page 9/21

Stem gluing

✔ Mark the clinker lines on the aprons to ease plank lay down. If you have the kit, small notches

give the position of clinker lines. The marked line is the edge of the « inside » plank, which is
laid down first.

✔ The false stem is laminated at this stage, using the stem as a mould. Note that cut-out have

been made in the centreline layer to allow clamping.

This document is the property of François Vivier Architecte Naval. It shall not be copied, transmitted to any other person,

nor published as a whole or partly, without the written consent of the architect.

March 2017 Building Morbic 12 Page 10/21

✔ The fore bulkhead (# 5) is made of 2 layers of 6 mm plywood. The bevel is obtained in the

same way than for the transom. Add a batten on top (fore side) which will be used to lay down
the deck. Shift this batten upward (3 mm about) to allow bevelling according to sheer.

✔ The fore bulkhead and stem are assembled, taking care of orthogonality.

Then all parts are laid down on the main girder:

✔ Bolt bulkheads and stem to supporting station moulds:

Note that the mould is recessed from the bulkhead to avoid undue gluing during the planking process

✔ Set down the longitudinal bulkheads which must be glued to bulkhead 3. Add an epoxy fillet or

a batten inside the buoyancy tank.

✔ Lay down the transom which is glued to the ends of the longitudinal bulkheads. Glue inside

the transom the beam (35 X 25) which will receive the aft deck. It is better to bevel this beam
before gluing (take off the angle on plan 21).

See the epoxy fillet between transversal and longitudinal bulkheads

Transverse bulkheads have to be bevelled to receive the hull planking. Use a long batten to estim ­ate the quantity of wood to be planed off.

The mid-bulkhead (# 3 under main thwart) will be cut out at centreline at a letter stage, just before
setting down the centreboard case.

Longitudinal bulkheads do not require bevelling. Just do it if necessary when laying down the hull
planking.

This document is the property of François Vivier Architecte Naval. It shall not be copied, transmitted to any other person,

nor published as a whole or partly, without the written consent of the architect.

March 2017 Building Morbic 12 Page 11/21

6.3. Strakes preparation

Appendix 2 The patterns give the final shape of strakes (hull planks). They may be cut without any margin, ex-

cept at ends. The average overlap between strakes is 20 mm. However, the actual overlap may
vary between 10 to 25 mm to take in account possible inaccuracies of the design and building pro ­cess.

The sole (bottom planking) is made of 2 scarfed planks. Cut-out first both parts, then assemble by
scarf taking care of a perfect alignment. For that purpose, draw the centreline on each plank.
When gluing, check alignment and hold in place with a few screws of nails in order to avoid any
slippage.

For other strakes, scarf firstly the full plywood panels, then mark from the patterns and cut-out.

Attention: this require space. If you build in a small room, it is better to scarf panels and cut-out
strakes before setting up the building frame.

Then sheath the inside face of sole, as it is easier to do it now that into the boat at a later stage.
For the same reason, you may also glue and screw from outside the foot rests on this sole.

6.4. Lay down of the sole and first strake (garboard)

Plan 12

Plan 21

Plan 22

Sheet 51

The sole, when glued to the structure, will make the boat definitely stiffer. Bulkheads are to be per ­fectly aligned before gluing. For that purpose, draw the centreline on the inner face of sole and on
each bulkheads. Check also the spacing of bulkheads (see plan 12). This plan gives also the posi ­tion of the fore end of the centreboard slot, in order to get the good longitudinal position of the
sole.

The fore end of the sole, or rectangular shape, will be plane away when fitting the false stem. In fi­nal, only a small amount of wood will be kept.

The liaison between the sole and the garboard is done on the stitch and tape principle. As the sole
is thicker than the garboard, it has to be planed out all around, on the outer side, to get an edge
thickness of 6 mm about. See plan 22.

In practice, only a few number of wires is required, in addition to some temporary screws into bulk ­heads. Then the joint is filled-up with epoxy putty. When cured, remove the wires and fill the re ­maining open joints. Fair and sheath with a glass tape.

The following tasks are made at later stages:

✔ Sheath all the sole and garboard area, to get a tough skin, wearing resistant.

✔ After turning over, apply epoxy fillet and glass tape on the sole/garboard joint and sheath the

sole and garboard area. There is often sand in the boat and a tough surface is also much bet­ter. Aft, sheath also the lower part of the longitudinal bulkhead (2 or 3 cm).

6.5. Lapstrakes lay down

Sheet 43

Sheet 44

Sheet 12

The recommended technique is to glue the strakes using temporary screw (sheet 44). They are
also glued to stem and transom. Strakes are normally laid down without adjustment. As already
written, the overlap may vary around the average 20 mm value.

The small thickness of strakes makes neces­sary in some area to fill-in a V joint with an
epoxy fillet (see sketch).

The general process is as follows:

✔ Mark and plane out the bevel on the previous strake.

✔ Lean the strake being fitted against the building frame, well positioned according to notches in

bulkheads/station moulds and according to marks on the stem. As said, the average overlap is
20 mm.

✔ Shape the ends of strakes as explained in sheet 44.

✔ Then glue the strake hold in place with some screws into stem, transom and bulkheads. Tem-

porary screws may be used into station moulds.

✔ Lay down alternately strakes on port and starboard sides.

This document is the property of François Vivier Architecte Naval. It shall not be copied, transmitted to any other person,

nor published as a whole or partly, without the written consent of the architect.

March 2017 Building Morbic 12 Page 12/21

Strakes lay down

6.6. External completions of the hull

Plan 21 Before hull turning over:

✔ Fit the false stem. Shape this false-stem in order to get a flat surface on the fore end (14 to 16

mm wide) allowing to screw down a brass keel band.

✔ Apply epoxy resin on all plywood edges and add epoxy fillet into joints when required.

6.7. After turn-over

Plans 21 & 22

Lay down 2 transverse temporary battens over the hull, one at station 1 and the other at station

4.2, to check the hull is not twisted.

Lay down the fore deck and the aft decks/seats to check the curvature of the hull planking. If ne ­cessary, the hull may be squeezed with a rope or spread with temporary beams.

Check that the hull is well shaped. If necessary, it is possible to adjust the sheer line with a plane.
At this stage, the hull is still flexible. It will become stiff after adding other inside structure elements.

Then saturate all plywood strakes edges with epoxy resin, as already done outside. Sheath the
sole-garboard joint with a tape and sheath the full sole and garboards with cloth and epoxy as
shown on transverse structure plan.

6.8. Rub-rail, gunwale, quarter knee

Plans 21 & 22

Appendix 1

Lay down the gunwale (inside planking). Be careful as the glued parts are very slippery. In addition
to clamps, place some screws.

In order to ease gunwale adjustment at ends, it is made of two parts. The joint is just under the
thole board, so hidden when the boat is finished.

In the thole pins area, the gunwale is doubled with a second layer. Take care not to chamfer the
first layer in the doubled area, as well as in the quarter knees areas.

As we have not made any rabbet to cover the hull plywood edge, gunwale and rub-rail will be
placed about 2 mm above plywood edge as shown on the sketch. The slot will be filled up with
epoxy putty. If the gunwale is to be varnished, use wood powder to thicken epoxy in order to get
an appropriate colour. Then the full assembly may be planed out:

Cut out, adjust and fit (glue and screw) the quarter knees. Screw are preferably set from outside
planking. The quarter knees shape is given on the full size patterns.

A lower rub-rail may be added at the low edge of sheer-strake. It gives extra protection and a more
traditional look.

If the gunwale is varnished, it is preferable to cover screws with wooden bungs, or at least with
epoxy putty made with wood powder.

This document is the property of François Vivier Architecte Naval. It shall not be copied, transmitted to any other person,

nor published as a whole or partly, without the written consent of the architect.