The Bruce Roberts Steel or
Aluminum kits contain:
All plate parts belonging to the hull, deck and superstructure that
are accurately cut to size are included. The parts are marked with the
appropriate part number and engraved matching marking lines to assist
in the assembly and location of the part in its position. All framing,
stringers, engine beds, 'T' sole bearers, deck beams, deck stringers
and all exterior plating, plus 3 steel bulkheads and stiffeners is
included. Windows and doorways are cut out as required.
In the case of radius-chine hulls, the radius plates a rolled to the
perfect shape and NO fitting is required. Complete assembly and
engineering plans supplied. A building jig is supplied with the kit.
Delivery is often included in the quoted price.
Cutting method is Plasma / Oxygen, ensuring highest accuracy and
smooth edges. Plate parts are cut from either Marine Grade ALUMINUM or
Grade ?A? Ship-building quality STEEL that has been coated with
factory applied Sigma weld MC welding primer. We use and recommend
steel plate that has the official designation ISO standard 10474 or EN
10204 with 3.1.B certificate.
All pre-primed profiles belonging to the hull, deck and superstructure
are supplied in sufficient quantity and are in factory lengths of 6 M
/ 20 ft, coated with factory applied Sigma weld MC welding primer.
Openings for windows and doors can be cut or only marked as per
customer's preference. Bulkheads are supplied complete with stiffeners
and are in accordance with classification rules and safety
regulations. Cold forming of plate parts is included where this
requirement forms part of the design. Basic engine foundations are
integrated into the construction.
A Setting up jig with the correct shape of the hull plates that can be
used as building jig for the entire hull after reinforcement plus
there is a extensive building manual including detailed drawings,
parts list and welding instructions.
In these days where both the local authorities and the better informed
builders themselves, it is important that the construction
calculations are in accordance with prevailing classification society
so this factor is part of the preparation of any Bruce Roberts kit.
Each kit or set of cutting files comes complete with about 15 sheets
of detailed assembly drawings with written instructions and check
measurements for assembling each part of the kit. The drawings cover
assembling the frames, setting up the building jig (supplied) on to I
beams or similar base. These extensive drawings take you right through
the welding up process from start to finish.
Also are included several sheets of detailed engineering drawings that
cover the installation of the main engine(s), ?take home engine?,
generating set, exhaust systems, fuel systems, fuel and water thanks
METAL KITS ASSEMBLY INSTRUCTIONS:
Throughout these instructions we will use
the word metal which may apply to steel, aluminium or copper-nickel.
There will be variations between the handling of the various materials
and these will be drawn to your attention as necessary. YOU WILL NEED
TO READ and absorb all these instructions BEFORE you start the
assembly of your kit. These instructions are intended to introduce you
to building from a kit but are NOT intended to replace good metal boat
building practice. If you are not already a competent welder then
please seek assistance.
Few of you will understand (or want to
know!) the huge amount of work that is required to turn any boat plan
in to a cut-to-size boat kit. Every part has to exactly match that of
its neighbor, the slots need to be exactly in the correct locations
and everything must fit perfectly together to enable you to complete
the assembly of the hull, deck, and superstructure with the minimum of
Despite our best endeavors and
attention to detail in developing the kit and the cutting of the metal
parts, some parts may not fit or appear to have the wrong shape.
Before rushing to cut and or shape parts to fit the hull, carefully
check the drawings and measurements from the surrounding parts to
ensure that nothing else is wrong.
The first thing to realize is that the
kit differs in many ways from the methods you would use to build a
metal boat from scratch. The kit is far superior to anything you could
achieve by starting with the plans and delivery of raw steel plate and
the various profile bars that are needed to build your metal boat.
Most metal boats built from scratch
are built upside-down…most boats built from cut-to-size metal kits are
built UPRIGHT. Not only is this a more appropriate way to
assemble the kit but also it saves cost and inconvenience of having to
turn the hull.
To make sure that you take notice of
one very important piece of advice, we will state it here as well as
at the appropriate time:
YOU MUST TACK WELD THE
COMPLETE HULL DECK AND SUPERSTRUCTURE TOGETHER BEFORE YOU RUN ANY
Failure to observe this advice will
almost certainly ensure you will end up with an unfair boat requiring
a considerable amount of filler. In any case do NOT OVER-WELD
or try and run long welds at one time.
2: RECEIVING YOUR KIT.
Depending on your location or delivery arrangements your kit may
arrive on a flatbed truck or in a container. You should be aware of
these arrangements before the actual date of delivery so you can make
the necessary preparations to receive your kit.
The kits are normally packed on
pallet(s) and can be lifted off the transport using a small crane,
front-end loader, or similar equipment. You may find it more
convenient to "drag" your kit from the truck or container using a pair
or planks as a ramp. Once you have unloaded your kit you must make
provision to keep it covered until assembly is underway. Make sure
that the metal parts are not in direct contact with cement-based
floors like concrete, as this will affect the Sigmaweld primer.
You should go trough the kit and
identify each part or group of parts so you can store these in the
order that they will be required. Due to the requirement of packaging
for transport it is impossible for the kit manufacturer to stack
everything in the order you will be using the various parts…you must
take care of this. Later in this text we will suggest the order of
assembling your kit so you will be aware of which parts you will need
at each stage. If you do not find a particular part at this stage …DO
NOT PANIC…there will be so many pieces that it will be easy for you to
overlook one or two at this stage. If after several checks you find
one or more parts missing then do contact the supplier of your kit so
they may put the matter right.
3: ASSEMBLY SEQUENCE.
FOR MOST HULLS: The first item you will need is the setting up
jig. The metal "castles" that come as part of your kit will support
the transverse profile jigs. The setting up jig is intended to get the
assembly of your hull started and is NOT INTENDED TO SUPPORT THE
BOAT during the entire building process. After you have the bottom
plates tacked together you should consider adding extra support and
bracing to the structure.
For most hulls, the general assembly
Assemble the jig.
Bottom plates into the jig; line up
the markings for frames and tack weld together.
Assemble web-frames in accordance
Position bottom longitudinal
stiffeners on bottom plates (very small tack welds only).
Position frame over longitudinal
stiffeners onto bottom plates, starting with the middle frame, work
your way aft ships and then from the middle to the bow.
Tack-weld frames in position,
observing the markings on the plates indicating the correct position
of the frame. The direction of the arrow in the marking indicates
the direction of the plate thickness. Always start tack welding at
the bottom centerline working your way outward.
Tack-weld bottom longitudinal
stiffeners to web-frames
Insert side longitudinal stiffeners
into web-frames and continuously check the frame spacing.
Position side-hull plates starting
at transom and tack weld to web-frames only.
Tack weld longitudinal stiffeners to
side and aft-hull plates. For hulls with build-in spray-rails start
at the bottom and work your way upwards.
Position rear hull panel (transom)
and tack-weld to bottom and side plates.
deck-stiffeners and tack-weld to web-frames.
Position deck-plates starting aft
and tack-weld to web-frames only.
stiffeners to deck plates.
Position superstructure walls and
tack-weld to web-frames.
Position and tack-weld roof-plates
This is the recommended sequence for
most type hulls. Depending on the facilities of your workshop and
building site, variations may be required or preferred. The better
equipped your workshop is with overhead lifting equipment and
equipment the easier and more smoothly will your job proceed. We do
recommend that you read some of the literature available on metal boat
building, which will answer many of those general metal boat building
questions that are sure to need clarifying as the project proceeds, if
only to get familiar with the terminology of parts and components of
your kit. Contact your supplier for titles available in your area.
FOR HULLS WITH LONG KEELS INCLUDING
The Spray and similar hulls are
unusual in that the keel structure should be assembled at the same
time as the bottom plating. Take care that you do not "squeeze' in the
tops of the keel, use the webs as spacers. After you have positioned
the bottom plates, the keel sections and the transverse profile jigs
in their correct location you may start to tack weld the bottom plates
to the keel sides.
FOR SAILBOATS WITH FIN KEELS:
Sailboats with deep keels will have
the keel installed after the hull is completed. The "canoe body"
should be built from the bottom of the hull upwards in a similar
manner used to assemble a powerboat hull. The webs will be arranged so
you can later add the keel after raising the hull into the correct
The idea of this method is to allow
you to work on the hull deck and superstructure while the boat is
lower and thus more accessible. The exact method and order of assembly
may depend on the availability of lifting equipment and your general
In most cases you can start by laying
the bottom plates in the transverse profile jigs and with the aid of
the "castles" so position the plates that you can start to tack the
hull plating together along the centerline. You will next be able to
install the bottom sections of the frames and webs in their correct
5- WHAT YOU NEED TO KNOW ABOUT WELDING
Attempting to construct a metal boat
kit leads us to believe that at least the basics of arc and or Co2
welding are known. If in doubt about your abilities to weld, improving
your skills on some scrap pieces of metal would be advisable as there
are no great secrets in general steel welding but practicing would set
you of to a good start right at the beginning.
Welding aluminium or copper nickel
should not be attempted without proper knowledge of the materials and
welding sequences involved and should always be carried out in covered
and clean surroundings.
The metal kits are constructed in such
a manner that the strength of the hull & deck is created from the
build up of the frames and stringers as interlocking sections,
HEAVY AND CONTINUOUS WELDING OF FRAMES AND STRINGERS SHOULD BE AVOIDED
AT ALL TIMES.
Especially important for all plate
joints during the assembly of the hull is DO NOT APPLY CONTINUOUS
WELDS. The plate joints should be ONLY TACK WELDED in three
locations, one weld at the each of the ends of the join and one in the
centre of the join. These tacks should be no more than 2 inches or
50mm long. If you weld the plates on the floor you will end up with a
"hard-spot" in the hull plating.
All parts of your kit are cut to a
precision of 2 mm and are designed to be welded together without any
opening between the parts. Some plates will need to be beveled before
tacking in place or you may prefer to make the bevels after you have
tack welded the plates and just before running the final welds. In all
cases good metal boat building practices will prevail.
After the hull & deck are
COMPLETELY TACK-WELDED together, the process of finishing welding
can take place. The secret of creating a fair hull & deck after tack
welding is completed is to use a fairly high amperage and speed
setting of your welding equipment. Welding with too low amperage and
slow speed will create lots of heat on the spot and less penetration
of weld material in the seam, causing strength problems and lots of
grinding weld material away to obtain a smooth surface afterwards.
This in turn would weaken the weld again.
Using common sense and practice should
leave you to create a smooth and fair hull & deck structure with very
little distortion. IF IN DOUBT ABOUT YOUR SKILLS, SEEK ADVICE.
Any metal construction company or
competent welder can help you with the basics. Always observe personal
protection and safety regulations.
6. ASSEMBLING YOUR KIT.
With the arrival of your metal kit,
you received a packing list containing the names, numbers, and
quantities of all the parts in the metal package.You also received one
or more large-scale drawings showing all the parts as flat surfaces
and more or less grouped together as they appear in the metal kit and
a number of small drawings showing the assembly of the frames with the
Studying the large scale drawings will
give you a first insight in the position of the various parts and it
becomes apparent that the numbering is as much as possible a logical
sequence of the way the parts assembly progresses.
Prior to using these drawings, we
advise to make some copies of the drawings or parts there off or cover
them with plastic as they could easily be destroyed during the
construction and welding.
Using the packing list and the
drawings you can now make a check to see if all the parts are present.
For ease of recognition you will find that frames etc. are numbered
with 4A, 4B, 4C etc. thus every time you find a number 4 and extension
A or B etc., they belong to the frame no.4.
The cutting, collecting, and
identification of parts during production is a manual process. This is
why parts may be given incorrect numbers and even get lost, in spite
of our thorough quality and quantity control procedure. Checking and
verifying all parts against the packing list provided and keeping
unidentified parts aside until the end enables you to identify the
missing parts and incorrect markings on parts for clarification with
Apart from the plate parts, your kit
also includes a selection of profiles, supplied at factory lengths, as
listed the Packing list. Each bar needs to be cut to the length
required in its position in the construction as detailed on the
Construction Plan provided in the set of drawings.
Now that you have collected and sorted
all the parts, the frames can be tack-welded together by using the
small drawings and the given measurements as reference.
Prior to welding, use an angle grinder
and create a "V" of approx. 60° at the seam to be welded.
This means 30° angle at each plate
edge. Doing this will give you better penetration of the welding
material, adding strength to the hull. We use the word tack-welding
again as it would be tempting to finish welding the seams fully.
Some models have flat or angled bars
added on the inside edge of the frame plates for additional strength.
Check the Construction Plan provided. These so called Girders are best
fitted as soon as the frame parts are tacked together, before placing
the frame in its position in the hull.
On larger boats it might be an
advantage to only weld the bottom parts of the frames together and put
the side frames up after the frames are in place on the bottom plates.
Your own judgement is important here.
Having prepared all the frames in this
manner it is now time to prepare the building jig.
With the metal kit you have received 2
or more jig parts as shown below.
These supplied parts are only
initial shape supports and CANNOT BE USED AS FULL BUILDING
FRAME WITHOUT SUBSTANTIAL STIFFENING AND CROSS BRACING.
The supplied jig parts could be placed
on a concrete underground, leveled, and stiffened.
In case no solid underground is
available, the use of a couple of heavy RSJ’s picked up from a
local scrap dealer could do the trick.
The distance between the jigs is determined by the position of each
frame (web) in the hull, whereby the jig number is the same as the
frame number (f.e. Jig-part J5-2 is at frame 5).
In case the "jig" parts stay in place
during the entire construction, it would be advisable to tack-weld a
flat bar across the top of the plates to spread the point loading and
avoid possible damage to the hull plating.
Now place the bottom plates on the
prepared jigs or building frame and tack-weld together at a
number of points.
We refer here to paragraph 2 in
relation to sailboats like the Spray series where also the keel is
placed under the bottom plates at this stage.
For those of you who are new to this
type of boat building, having placed the bottom plates on the jigs, it
seems they are never going to fit.
Start tack welding at the
location roughly in the middle or somewhat aft of the middle after
lining up the lines on the plates and position of the plates.
When you now go forward or backwards
from the tack-welded position you can help the plates get in
shape by having some helpers pull up the sides and using a trolley
jack underneath the middle join of the plates until the seams touch.
Now tack-weld at this point and go to the next position. At the
bow you would probably need a hand block and tackle to pull the sides
of the plates together as some tension will be experienced here.
DO NOT FORGET TO SECURE THE POSITIONS
OF THE CLAMPS AGAINST SLIDING AWAY.
Having finished tack-welding
the bottom plates together, start placing the longitudinal stiffeners
at the markings on the bottom plates whilst lining-up the slots with
the position of the frames (webs), as indicated by lines on the plates
and use the large scale drawing(s) as reference. Only tack-weld these
longitudinals to keep them in place for the time being. As frames will
have to be slotted over these longitudinals, we recommend to tack-weld
only to the bottom plate in the middle between frame positions, which
allows you to align these when putting the frames in position.
Then start placing the frames (webs)
which slot in the longitudinals. Position the middle frame first and
tack-weld it to the bottom-plates in the centre, then pull up the
bottom plates towards the frames until they fit snugly and
Depending on the shape of your hull,
we recommend to work your way aft first, thereafter from the middle to
If you have put the frames together
completely, use some temporary bracing on the upright sides of the
frames, as they are likely to flop about a bit.
Now we place the stringers in the
slots of the frames on the sides and slightly tack-weld at some spots
to keep them in position.
We do emphasize again, ONLY
At this stage you have already created
a strong and solid base of the hull and the time has come to bring the
side plates into position. This is best done by using a simple
overhead gantry or the use of a forklift truck.
Pick up the side plate(s) by using a
plate clamp on a chain connected to a block and tackle or forklift
leg, make sure the plate is more or less in balance when it is hanging
in the air and bring to its allocated position.
Use a helper to put a point of the
seam in the right position and tack-weld.
Continue by moving the plate up or
down a bit with the block and tackle until the entire side is in
position and tack-welded. Place some tack-welds on the uprights
of the frames as well.
The side plates nearer to and at the
underside of the bow will show some tension and can be pulled in place
by attaching a chain on the outside of the plates and pulling them
To attach a chain and/or block and
tackle to a plate, tack-weld a temporary eye or something similar to
the plate. By only welding on one side of such plate(s), you
can easily remove these again by bending this plate until the weld
In the case of radius chine sailboats,
the radius chine sections are not used at this stage; we will come
back to those later.
Next the transom plates, bathing platform where applicable, stern
plates and all other plates belonging to the hull are offered up in
position and tack-welded in position.
Especially where rounded corners are
used, offer the particular plate up to the position it is to be used
and check or make the correct radius in the plate prior to tack
REFER BACK REGULARLY TO THE DRAWINGS
AND CHECK INTERMEDIATE AS WELL AS OVERALL DIMENSIONS.
Now the deck plates, superstructure,
fly-bridge where applicable and all other super structure plates can
be offered up to the hull and tack-welded into position using
the gantry or forklift truck to lift them onto the hull.
Do make sure the support strip(s)
under the deck and cabin roofs, where applicable, are placed first in
its slot(s) in the frames and beams.
In those cases where professional
lifting equipment and space is available, an option would be to
tack-weld the superstructure together at floor level, braise
temporarily and than lift the entire sub structure onto the hull.
FOR RADIUS CHINE HULLS:
Having tack-welded the
entire boat together, you now turn your attention to the radius
We have supplied you with the
appropriate amount of section to fit in the left over opening in the
As you checked the metal kit on
delivery, you have seen they are all similar sections, just one radius
rolled into them.
Now you can carefully hold a section
against a position on the opening in the hull and using a helper
scribe the plate with a sharp tool or pencil and grind, nibble or cut
the edges until the plate fits in position.
into position and continue until all radius plate sections are in
you are now looking at the shapely result of your perseverance.
Of course you have run into some
difficulties during the building process and maybe even cursed a
couple of times but it must be clear by now why we told you time and
time during this manual ONLY TACK-WELDING. Any possible mistake
you may have made was fairly easy to rectify, as you only had to grind
a couple of small welds away.
However careful the cutting of the
material was prepared and cut, the material can behave unexpectedly,
for example the grain in the plate runs diagonal and will resist
shaping into the required form. This will require additional effort
and force to get the plate to fit.
Although we aim for perfection,
mistakes do occur, however the general consensus is that if you have
to cut or reshape a plate (with the exception of radius plates)
somewhere something is not right.
7. FINISHING THE ASSEMBLY.
Now the time has come to
finish the welding process.
Firstly, finish welding all the seams
between the frame sections applying a full weld. All slotted
connections between frames and bottom and side longitudinals are to be
welded in full on at least two opposite sides of the connection.
Then apply intermittent welds on all
frames and stringers to the hull and superstructure plating using the
rule 50 mm. (2") weld, 150 mm. (6") clear, 50 mm. (2") weld. Alternate
the weld one side of plate, other side of plate and so on.
DO NOT CONTINUOUSLY WELD ON ONE SIDE
OF THE HULL but weld a bit one
side, the other side and so on to avoid pulling. Do not underestimate
the forces coming free when welding.
Now the hull should be welded.
In case you have not made a 60° "V"
between the seams of the plates yet, no problem, use an angle grinder
and cutting disc and cut a groove in the plate where the seam is
located. Not as nice as having a "V" made first but the result will be
the same. As explained before, alternate welding from side to side and
finish the welding process.
The hull under the waterline must be
welded inside and out. All
other welding can be done one side only.
Grind away surplus welding whereby we
advise to pre-grind the welds with a heavy duty grinding disc and
finish grinding with one of these softer flexible discs, ready
available in the trade, to avoid having to use filler on the weld
seams.Clean the surface and apply a coat of primer and the basics of
your pride and joy are ready for finishing.
We recommend you postpone the engine as long as you can, not
because of the weight, more because these parts cannot be placed in
their final position at this stage and tend to be very much in the way
/ get damaged easily as long as they are only temporary supported
If you still prefer to lift the engine in, no problem as long as you
make sure that you spread the weight of the engine over at least three
transverse frames and always over two cradled frames.
Use some serious timber beams running parallel to the CVK and support
the beams on the lower horizontal part of the transverse frames.
Obviously best to skip # 9 which is still loose by putting some extra
dunnage on the adjacent frames to raise the timber beams. This will
also give you sufficient room to run final welds at the bottom,
especially important for the welding of the keel from the inside.
Handle the generator in the same way. Before you do all the above,
make sure your hull plating fully follows and touches the cradle parts
that have the same shape as the hull on all stations.
Finally, when placing the engine in it's temporary position, put it in
a place not interfering with your longitudinal alignment check which
should be done at regular intervals during the assembly process.
For the tanks, assuming you will be using pre-fabricated tanks, I
would recommend to leave those loose and get them inside the hull when
convenient. (normally make nice chairs or tool shelves during the
assembly). Weight is not an issue here.
The shape and dimensions of the tanks should always be checked in
place (as would the fuel-tightness), very difficult to modify tanks or
tank brackets when hull closed.