After building and finishing the two
floats, now it's the turn for
the main hull. Please click on the images to open an extensive photo gallery of
the various stages in the building process.
Before setting up the main hull, and while still having the room, I first made the beam bulkheads as these
requires a special construction for the folding mechanism. A rather big
laminating job with vacuum bagging. The first attempt is a bit disappointing,
with epoxy everywhere, not only on the part, but also everywhere else. Because
of a too sharp edge on the molded flange I pulled a big hole in the underside of
the vacuum bag. Getting a wet vacuum bag airtight again is quite a job. While
the resin clock continued it ended in a big mess. I left the workshop in my
underpants, and with epoxy in my hair (it's shorter now). Now I know again why I dislike vacuum bagging and like the vacuum
infusion so much. However, vacuum
bagging is the way to go for this complicated laminating job. Or just
hand-lay-up. But once used to the quality by a vacuum treatment, it's hard to be
content with anything less. I am very comfortable using it.
At the end, after eight vacuum bags, it's becoming
more of a routine with less mess and better vacuum bags. Practice, practice
Setup first main hull half: This is one of these
memorable stages. Not only the "real boatbuilding" work, at
least the fun part has just begun in this stage, but more memorable is
the fact that the hull fits in my small workshop as I had thought to myself.
It's a close fitting and a relief at the same time. I've started with the
starboard side of the main hull as the geometry of this hull half fits better
in my workshop.
I knew before that the height of the workshop is not enough to
join the two main hull halves, so the planning is to make the second hull half
and the joining to a complete boat in a bigger workshop somewhere else (still to
find that place). This will be temporary and the completing of the boat will be
again in my garage.
Layup dry laminate and infusion. The bag was perfect, the vacuum was
almost perfect, however after the vacuum was on, I discovered I had a batch of
wrong tubes. They look the same as I've had before, but these ones were pressed
together and useless for the infusion job. Very disappointing. As infusion was
planned for the next day (Monday, and with an announcement on the F-boat forum
for a live show on the webcam)) a quick ride to fellow builder Bert Hofman
brought the solution as he had enough tubes to help me out. It was late Sunday
evening (or better said Monday morning very early) when all tubes were replaced
by the good ones.
Below the video (14,6Mb) and at the right the moving animation (1 Mb) of the
Beam bulkheads and folding system setup : Making and
positioning the carbon lower folding strut anchors turned out to be a tough job.
I've had some worries because they are such an important structural part of the
boat. The first two attempts were a bit disappointing but finally I developed
the right method to wrap the carbon around the anchors blanks.
The building project until now was mainly a matter of forming foam into hulls,
laminating (ok, better said infusing) and gluing bulkheads into position. It
gave me the feeling of putting a boat together, but not constructing something.
However, mounting the beam bulkheads and lower hull strut anchors with the
accompanying reinforcements is much different from that and gave me the feeling
of a constructing work. I was already impressed by the design drawings and
engineering quality of Ian Farrier and the way these elements are being
constructed is more than an confirmation of that.
The daggerboard case is made of marine plywood and I discovered the hard way
(at least after two failed vacuum bags) that the porosity of the plywood makes
it impossible to make an airtight seal with sealant tape onto the wood.
Something to remember for all wood builders. The vacuum infusion was done with
two bags, one for the infusion and one for the vacuum integrity. A stopgap and
not something to copy !
and cockpit area. The finishing of this first main hull half with all the
structural bulkheads and the making of the cockpit coaming, emergency escape
hatch and the safety compartment.
On the left a video of the
infusion of the escape hatch coaming.
the starboard main hull half: This went on quite straight forward.
Turning the hull with the four tackles was exciting and she went over with literally just a couple of
millimeters to spare
Most of the work was cleaning up the mess and to find a new place for
all the stuff that I still don't want to throw away. The half hull is
remarkable stiff and instead of starting the other hull half I decided
to start with some more interior work as access to the hull is great in
this stage. However, life would be easier if I knew what do with
the interior ..... decisions, decisions .........
Interior layout: I finally decided about the layout of the interior. The
biggest change compared to the
standard aft cabin layout is the galley on
starboard instead of port. Main reason for this is that I still like "the
office" on board, which lead to a rather conventional layout, in particular in
combination with a quarter berth. Because of the galley on starboard the settee
in front of this is now shorter, but still useable as a (sea) bunk with the feet
through an opening in the cabin bulkhead. Above that the diesel oven is situated. Galley top
can be extended by folding down the backside of the settee back. The dinette is now two
meters wide and can be converted into a large spare double bunk. Also the shower
is a little wider. Without rebuilding the interior this can accommodate six (with
table down eight and with spare bunks in the floats even ten) Cooking is on a
ceramic diesel stove and in addition to this a fully gimbaled single
cylinder burner, positioned in a dedicated housing and well ventilated outside.
Of course the interior question is a matter of personal taste. I think this is a
good sea going layout and at least for now this design gives me some peace of
Systems: Click on the colored system items in the layout
drawing below to open a principle sketch about the subject. I will add more as
Carbon bobstay anchor:
Some time ago I had a look on the composite department of
and there I learned that they put a lot of effort in saving weight at the ends
of airplanes and wings. Not a surprise of course but this reminded me of the
quite heavy bobstay anchor in the bow of the F39. In spite of the fact that I
prepared the piece of stainless steel to fasten into the bow, I decided to make
a much lighter carbon one, almost in the same way as the carbon chainplates.
Moving to another workshop: Quite unexpected and totally on the spur of
the moment we bought a new house ..... Sometimes that one in a lifetime moment
comes along, in our case a water villa with a jetty large enough for mooring our
F-39 trimaran. So, the other "dream" we had, living in a
house near the water, has become a reality now and we will move to our new place
by the end of this year (2009). Which means I have to give up the workshop
at home and move the boatbuilding project to the workshop of our company.
This of course is a temporal solution with the necessity of getting in a hurry.
This means from now on I will focus on finishing the F39 on the outside and get
her in the water to tie her up along the jetty of our new home. Further work on
interior, hardware and rigging will be delayed till she is at home again.
Setup of the second main hull half. Again a fun
part to do. Working in the new workshop looks to be much faster due to more
space, better equipment, less distraction and less socializing.
And now there are a lot of critical observers (i.e. colleagues). No doubt
they will inspect the work on Monday morning to discuss the working rate of
their "boss" ..........
again. Fitting out the new workshop turned out to be much more time
consuming than anticipated. But now everything is in accordance with my wishes
and this weekend I had the feeling to continue the boatbuilding again instead of
all kind of other things, like organizing and cleaning up too much company
materials, dragging along too heavy girders, hoisting and mounting too heavy
winches, organizing and connecting too much electrical wires, building and
pulling down again an incomplete scaffolding, which despite some missing
components was strong enough to hold up the main hull half for a while, which by
the way wasn't necessary if I had done the electrical winches first, etc.
infusion of second main hull half: The handling of all the glass and vacuum
materials is now much more convenient in this spacious workshop. However, in my
enthusiasm I forgot to add some reinforcements in the window area and the area
of the anchor locker. While writing this, the inside of the hull has been
covered with the vacuum materials except the vacuum bag. Next weekend I have to
fix that .......
one of the hottest days of the year (Saturday July 11 2010)
the vacuum infusion of the second main hull half went
flawlessly. I few hours before I was desperate not being
able to find a big leakage in the vacuum bag. At first I
thought having found the culprit, a forgotten connection of
a vacuum line. But after I repaired that nothing changed.
To be able to hear better, I put the vacuum pump outside the
building, however I knew that the leak was probably too big
to be able to hear. I spent the whole Friday evening and
Saturday morning on finding the leak. All kinds of scenarios
went through my mind, including the worst, a poreus or a
punctured hull. Just before I thought I was getting crazy, I
noticed the cleaning lady who was still in the building on
this Saturday morning. Knowing that women are much more
patient, I asked here to help me finding the leak. After 5
min (!?) she found a small leak in the bag. Unfortunately
nothing changed when I closed it with a piece of tacky tape.
Some minutes later she found the real wrongdoer, a big
square in the bag, hidden in a pleat. She made my day!
Thanks Angela! Now, I got some vacuum and the rest of the
leakages were easy to hear and I even finished with a
The drop test (vacuum pump off) resulted
in a not worth mentioning loss of
vacuum. Room temperature was 32º Celcius
and so was the resin. Just perfect for a
fast infusion. Click on the above
picture for the photo galery.
side folding system setup and beam bulkheads: When working on the starboard
half I made all the carbon lower folding strut anchors, but not the complete
anchor assembly for this port side. So, before putting in these carbon anchors,
I first had to do some unfinished business on the carbon anchors. Cook them in
the oven (this time not the one in the kitchen) and making the total anchor
Maybe it looks like I always have the things under control.
But that is only apparent and silly mistakes are indeed made.
After I freed
the two carbon anchor assemblies from their vacuum bag and
was preparing to mount the assembly in the hull, I
discovered that the base plate was shorter than the
anchor….. F**###(censored) In a fit of madness I had the
base plate mounted in the wrong direction. Itself is not so
bad were it not that all the UD fibers are now running in
the wrong direction. Too bad of all the beautiful laminate
work (and a waste of three days).
There is a lot of
laminating work to do around the beam bulkheads with up to
20 layers of UD fabric in some areas. This construction
looks to be real solid and bullet proof. As the lamination
and bond to surrounding areas is critical I try to be very
meticulous in this area.
milestone, Starboard meets port: Here some photo's of the joining of the two
main hull halves. Overall the hull halves fit very well together without
noticeable misalignment. On Menno's Blog (Dutch
F22 boat builder) I saw he used the two top battens to align both hull
halves. Great idea (thanks Menno) because these battens make the use of clamps
possible, which is much easier than bungling small wood pieces and screws.
I made the second (Port) main hull half a little longer in the stern. This was
not possible in my previous workshop due to the lack of space. After joining the
two halves I decided to make an extension to the Starboard half to make both
hull halves the same length. I don't know yet if I will make the hull one feet
longer, but doing this now in this stage is quite easy and I can always decide
afterwards to cut it off.
More bulkheads and details in the port side half:
I made all the other bulkheads in this port side after the joining of both hull
halves as aligning is much more easier this way. In the bow area I made the preparations for a second carbon chainplate. This is placed at the front of the anchor well and is intended for a heavy weather jib or storm jib. Since this is not a design feature, I've created my own solution.
All the "thinking" about the cockpit coaming and shelves in the cockpit area has
been done in the starboard half, so copying this to the port side was now done
in just one weekend. For now the inside parts of the mainhull are finished and
next is removing the frames and turning the hull upside down.
from the mold frames: A milestone again. A long weekend of preparations with
among other things unscrewing 7500! screws. The big event, hoisting the hull and
turning it upside down, was done in the next weekend. I like to do this on my
own, without onlookers, no hurry, good thinking and easy going. The hull is now
ready for further work on the outside.
External laminate from gunwale to keel: Before laying up the external
laminate, various "small" other jobs has to be done . Every time it is amazing
how a relatively small job takes much more time than expected. For example the
beam recess on the outside of the beam bulkhead. For cutting this recess area to
size and removing superfluous foam hull parts I needed all the cutting and
sanding tools I have, jig saw, reciprocal saw, multicutter tool, dremel tool,
powerfile, belt sander, angle grinder, powerplane and the handtools like
chisels, grater, hammer, file, multiknife, sandpaper, etc. and this all within 5
square ft . The four beam recesses took me two days with a lot of itch (from the
glass dust) as a result. Then some foam fill pieces, which took another whole
day. Everything is taking at
least three times longer then expected .....
I made a little change in the lay-up schedule of the external laminate in the
bottom of the hull. The plans specify an extra glass 0/90 layer in the bottom of
the hull, for abrasion purposes and also for the balance between the 0º
direction of the fibers inside and outside. As an alternative I've used a 45/45
Aramide (Kevlar) layer as the abrasion qualities of this type of material is
superior compared to glass. The topside of the Aramide fabric is covered with a
thin CSM layer, so the outside surface is glass and not Aramide. To compensate
for 0º direction strength I've also added a line of glass UD in the opposite
position of the internal UD layers. All in all a little heavier than specified,
but good for peace of mind ....
Bow pole: At first I thought of making the carbon bow pole by myself, also as a kind of exercise for making the carbon mast and boom in future. But for practical reasons I decided to buy a custom made bow pole, to save on time and to have a look in the kitchen of a professional carbon mast maker. Thomas Whilkes of Ceilidh Composite Technologies
(www.carbonmasts.com), the maker of the carbon bow pole, was so kind to discuss some ins and outs with me about making a carbon mast and the ideas I have to do this by myself.
The bow pole has been made in a female mould with carbon pre-pegs. The only thing I still have to do is making the
attachment points for screacher and spinnaker.
The bow pole is retractable and slides through a bow pole tube. To make the bow
pole tube I thought I needed the bow pole as a mould, but in hindsight it was not necessary to buy the bow pole in this stage, as the outside diameter is exact the same as a 125mm pvc drain pipe. So,
instead of the carbon tube I used a pvc drain pipe as a mould for the bow pole tube. With 7 layers of wallpaper I increased the diameter to 128mm for the easy gliding of the bow pole. The mould is finished with two layers of plastic film and a
Teflon coat between the films to be able to release the glassfibre bow pole tube from the mould.
In the mean time I'm playing with the RTM-Worx software, on the one side to make
the 3D model (that's fun) and on the other hand filling the model with material
qualities like resin viscosity and fabric permeability (that's just a puzzle to
translate in a lot of data)
Vacuum Infusion of mainhull bottom: I can say I now have a lot of experience
with making airtight vacuum bags. As a matter of fact, within this project this
is big hull vacuum bag number 9 and I thought it would be a piece of cake. After
all, it is not just a vulnerable foam hull but a foam hull with an airtight
internal laminate. And the joins of the Port and Starboard halves are covered
with a glass tape. So no worries about air tightness. I thought ........
Unfortunately this assumption proofed to be very wrong. I did some stupid
things, as using too long temporary screws
This area was also not air tight. Further more it seems there were air
channels in the
UD fibers in the forward beam bulkhead flanges. In short, it became a
headache vacuum bag, in fact the worse one I've ever made and it took much too
much time to get it right. As the infusion of the hull was planned and I had
appointments with some helpers I worked a continues 40 hours to get it right,
but unfortunately the bag was not good enough to start the infusion. A
disappointment for everyone and I had to
cancel the event.
After some more changes in the bag and improvements of the hull integrity two
weeks later it had to happen. Despite the fact the vacuum bag was still not
perfect the infusion started at 3.00 PM in the afternoon.
There were a few precautions taken to be able to solve possible problems during the infusion and this has worked out satisfactorily. Only the end counts and
despite the troublesome preparations it was again a success, a big relief and another milestone in the project. After a evening and night watch during the
cure of the resin I went home at 5.00 AM the next morning, tired but with a good and happy feeling.
On the left the video of the infusion.
"Upside down" interior work: While the hull is still in an
upside down position it is a convenient time to make the fillets that supports
the horizontal parts like the cabin floor, settees and chart table.
a material that is able to follow the hull shape and in the same time remains
horizontal I found Styrodur insulation foam to be the suitable material. All
positions are marked with a laser and the mold is formed by the Styrodur which
supported by temporary pieces of wood. Because of the light weight of the
Styrodur it is easy to fix with a 3M glue spray.
the hull upright: Turning the main hull upright is once again a milestone in
the project after which a new phase in the build starts. Farewell strong back,
the base construction on which all the hulls has been build, is now demounted in
little pieces and removed to the dumpster. With my four electrical winches under
the roof of the workshop, the actual turning went flawlessly. Of course I did it
alone again and to continue to fully concentrate without prying eyes of others.
With some extra ropes and the back-up of the workshop crane I took enough safety
precautions to avoid any risks.
For the support of the hull in the next phase of the build I've build two mobile
boat stands. For the subsequent assembly of the mainhull and the two floats the
boat have to be more or less moveable without too much of a hassle. I used the
hull as the mold for the two boat stands.
Preparations for the deck laminate: Now is the time to think very seriously
about the deck lay-out. During the whole build I have been pondering with a few
different options about rigging and hardware.
A deck stepped boom resolves the problem caused by lines (reefing lines,
outhaul, mainsheet) coming from the boom and interfere with mast rotation. I
made a mock-up to see how big of a problem this is and also studied a lot of
photo's of the big 60' Orma Tri's. My conclusion is that it is not worth the
extra trouble and the interference with mast rotation can be minimized by making
the line exit in the boom a little more aft of the mast. So the boom will be mounted to the
mast "the normal way" with the advantage that the boom induces the mast
I can see the advantages of the self tacking jib. However, there are some
complications. The track crossing the daggerboardcase interferes with the
daggerboard and the length of the track is limited by the folding movement of
the beam. Nevertheless (I'm getting older and looking for more sailing comfort)
I have decided to go for the self tacking jib and I assume that I am able to resolve
this in the finishing phase of the build.
Furthermore I decided to make a curved track for the mainsail sheet traveler.
Probably the traveler will be extended to the beams, but this is also of later
concern. The mainsail sheet goes to the winch on the port side of the cabin
And finally I have designed a plan to organize all running rigging from mast to
the winches on the cabin roof. With the above starting points and the
running rigging plan I am now able to put in all high density foam inserts in
all these places where hardware will be bolted down.
windows: The design calls for screwed down windows, but I don't like that
solution. Instead I want to glue them in a rabbet. The outside of the window is
then about flush with the outside of the hull. Determining the size of the
intended windows, also a little different from plans, was a challenge to get it
right. Finally I found out that I get the best appearance when the length
halfway the height of the window is about the same for all three windows. The
intended glazing material is still under consideration. The choices are
polycarbonate, acrylic or tempered glass. The windows are curved in two
directions and I prefer to make them pre-curved instead of pressing them in the
right curve. So, first thing is to make a mold with the right curve in it. I did
this by infusing a sandwich panel against the outside of the cabin wall. So far
the easiest part. Next is depending on which glazing material will be used ....
to be continued.
hatches: Well, it is a one-time opportunity so I choose for the difficult
option of flush hatches, which I found in Lewmar as the most economical ones. I
like fresh air and lightness and ordered one size 60 in the fore deck, two size
10 in the head and opposite passage way, two size 30 in the cabin roof and one
size 54 in the aft cabin. Flush with the deck means also a water drain below the
deck and that will be the next challenge to resolve.
cabin and cockpit construction: With respect to the vacuum infusion of the
deck there is a natural separation between the deck and roof of cabin and aft
cabin, as a result of the aft beam construction. So it is not necessary to
infuse the whole deck at once and therefore I have decided to first infuse the
roof of the aft cabin so I can finish the construction of the aft cabin and
To get some more room in the cockpit I made the seats 175cm long (my body
length) instead of the 168cm in the plans. (for nice romantic sleeping under the
stars, etc, etc.) After the mounting of the aft cabin hatch it turned out that
I've been a little too enthusiastic with the lengthening of the cockpit seats.
To make the hatch fit I had to make a cut out in the bridge and that just didn't
look very well. The other option, positioning the hatch more aft, is not
desirable because of the position of the main sheet track. Repositioning the
latter results in less pushing force in the boom to help mast rotation so the
mainsheet track dominates the position of the rear of the hatch. To resolve this
I've added two extra foam panels to the front panels of the aft cabin which
resulted in a correction of 32mm, which is just perfect.
Oh well, it seems you shrink as you get older.
construction:Duringthe constructionofmy boat, I have gottena lot ofrelationshipswithother boatbuilders, bothdomestically andabroad.
The exchange of experienceshasprovedextremely valuableand is also one ofthemany funincidentalsof sucha DIYproject. Herein the Netherlandsare twofellow boatbuilderswhoare both
Bert (F39) as a professional and
as a hobbyist. Thefabricatedpartsandthemold
forthe daggerboardare being
made byBert. And just
recently Nicoofferedtomake thetwo rudderplughalves for my F39.
Nico isan airlinepilot andspenthislonely dayssomewherefar away ina hotel roomontheprogrammingof hundreds oflines inthe CNCsoftware for myF39rudder. Great job Nico and thanks again.
as an intermediatelittle project,
I am nowworking on the two by
Nico's CNC router milledrudderplugsin orderto make asolid reusablerudder mold of it.
laminate and vacuum infusion. Finally it is time to finish the final
structural part of the main hull. This is also the last big vacuum infusion.
After this the hull is structural sound and finished except for the final post
curing. It is a big bag of 12x6m and the infusion strategy is again a simple
straight forward setup with just 4 single vacuum ports and a resin feeder line
going all around. At this moment the vacuum bag is ready but still not airtight.
the leaks are still to big so I cannot hear them and because of my bad hearing I
need some help with this (read younger ears ;) My goal is an infusion next
Designer Ian Farrier provides various options for the steering possibilities for
Unfortunatelynone of these
meets my needs.
There are two kinds of sailors. Those who like tillers and those
who like wheels. First of all there is the choice for
tiller or wheel. Just like everything else to do with boats, the wheel/tiller
debate is highly subjective. Both systems have their own pro's and con's. I
always had boats with tiller steering. For me this alone is a good reason for a
change. One of the advantages of a tiller, the simplicity with only a few moving
parts, is not going to work in the F39 centre cockpit. Like the wheel steering a
tiller also needs some kind of
transmission tothe rudder stock.
Then there is the aspect of space. The tiller devides the
cockpit in a starboard and port part. In this rather small cockpit this
compromises access to the coveted space under the dodger. The wheel on the other
hand devides the cockpit in a fore and an aft part. The helmsman has is own part
of the cockpit. I love that more than a sweeping tiller. Standing behind a wheel
while maneuvering in close quarters is more comfortable than with the tiller
between the knees. So, for me enough reasons to go on with a wheel.
Now what size? A wheelwith
asizesmall enoughto walk alongisnot what I want. Inthat case I wouldhave boughta sportsboat ;) So as
big as possible which turned out to be 900 mm. at a height of 800 mm.
As now these basic questions have been answered the next step is the most
difficult one. The decision about the transmission system. Roughly there are
four basic types,in order
ofmy preference :
1. Rack and Pinion steering - sound and
straight forward. 2. Transmission
steering - sound and good rudder feeling; 3. Cable or rope steering - in my opinion too prone for faults so
not for me; 4. Hydraulick steering
- no rudder feel, also not for me;
Transmission steering system: Although I prefer
the rack and
pinion option this system didn't made it till the
implementation stage. The space in the stern is too small and too narrow to make
an optimum use of a
wide angle geometry.
This smart geometry results in a
very direct steering amidships (where the loads are low) and a more indirect and
powerful steering at full rudder (where the loads are maximal). Also the
draglink from pedestal to rudder, with a length of almost 3m. (10ft) , needs a
lot of space for its movements (and a big hole in the aft beam bulkhead). Enough
reason to forget the rack and pinion system.
While maintaining the wide angle geometry I decided to change over to
transmission steering system made by the Danish Jefa. This system is based on the same principals as the rack and pinion system; the rotation of the wheel is transferred to a push pull movement via a gearbox and levers.
However, also due to the limited space behind the
stern, the proposed position of the bevel reduction gearbox is too far aft with
the consequence that the position of the torque tube doesn't match with the
height of the cabin bed. The torque tube is intended to go underneath the bed
The solution is to position the whole rudder 96 mm further forwards. This
means that the wideness of the lower step in the stern has to change from 374 to
278 mm. Resulting in a 210 mm. extension of the reduction gearbox shaft.
The above drawing is the final design and ordered Jefa parts. The bevel reduction gearbox
is housed in its own watertight compartment and separated from "outside" by a
watertight roller bearing. The connection of the autopilot drive is at the front
of the bevel box right under the steering pedestal. The autopilot drive will be
ordered at a later moment. The still missing pedestal is on my design board and will
be built in composite by myself.