ProFurl MK0 User manual

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Congratulations for the purchase of your PROFURL  in-boom reefing furling system.
Please read carefully this manual. It will give you to all information for fitting and using your
system in order to give you many years of dependable service.
IMPORTANT WARNING FOR USING
YOUR SYSTEM :
!The PROFURL boom is obviously heavier than a conventional boom.
Avoid uncontrolled gibing, specially with strong wind, as you could
permanently damage your system.
Reminder to gibe :
1 - take in or winch your main traveller and main sheet
2 - turn your boat to gibe
3 - gradually release your main traveller and main sheet.
You can even better fit a tackle as boom preventer (see drawing).
You can also fit a boom brake, but you must not forget to completely
release it each time you want to operate your system.

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CONTENTS
Page 2 Important warning to use your system
Page 3 Preliminary cautions
Page 4 General description
Page 5 Exploded view
Page 6 Tools needed for fitting
Page 6/7 Unfitting the hardware from the mast
Determining the height of the gooseneck
Page 7 Fitting the slide screws in the mast track.
Page 8 Fitting the gooseneck.
Page 8/9 Assembling the luff profiles.
Page 10/11 Fitting the articulation brackets onto the mast / the
sheave box.
Page 12 Measuring and fitting the upper luff profile.
Fitting the upper luff profile onto the sheave box.
Page 13/14 Cutting the boom to length
Page 15 Cutting the mandrel to length. Fitting the mandrel onto
the boom.
Page 16 Fitting the boom onto the gooseneck.
Page 17 Fitting the boomvang hound onto the mast.
Page 18 Adjusting the position of mainsheet bails.
Installing the control lines to the cockpit
Page 19 Fitting the mainsail
Page 20/21 Feeder adjustment.
Page 21 Adjustment of the boom angle to the mast.
Page 22 Using the system.
Limits for using the system
Page 23 Warranty conditions - Warranty form
PRELIMINARY CAUTIONS
The PROFURL in-boom mainsail reefing system is not designed to be installed on
wooden masts, or aluminium masts with track added with screws, rivets, glue or any
similar assembly. Fitting on a carbon mast is not recommended an requires special
skills. Please contact us.
Please check that there is no sign of severe corrosion on the mast which would
compromise the strength of the assembly.
The person in charge with fitting will be fully responsible for installation and adaptation
on board according to the specifications shown in this manual.

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I- GENERAL DESCRIPTION
Note : names in bold refer to parts shown on the exploded view (next page)
The PROFURL MK0 in-boom furling system includes :
1. One set of luff profiles (1 and 2) articulated on the aft face of the mast.
There are 2 different kinds of luff profiles: one 0.40 m long feeder profile (1) on which the
feeder (21) is attached, and several 2 meters long normal luff profiles (2) depending on the
mainsail’s luff length. One of these 2 meters long normal luff profiles (2) will be re-cut to
length at its upper end to match the expected luff length of the mainsail. The different luff
profiles (1 et 2) are connected to each other by mean of connectors/articulations (4),
which are fitted to articulation brackets (5) that will be attached to the mast track.
2. Articulation brackets (5) attached to the mast with 2 slide screws (7) slipped in the mast
groove. Every slide screw (7) has a thread and a flat end going through a hole of the
articulation brackets (5). The thread of the slide screws (7) receives a washer (33) and a
locknut (8) for attachment.
3. Connectors/articulations (4) are also used to connect the different luff profiles (1 and 2),
held by set screws (9). The lower end of the 0.40 m long feeder profile (1) will be
connected onto the gooseneck articulation (10), thus allowing the luff profiles (1 and 2) to
rotate together with the boom.
4. A sheave box (11) through which the original mainsail halyard is passing. The sheave box
(11) will be fit at the top of the luff profiles (1 and 2). It is assembled on the end brackets [2
times 5a], themselves being attached by mean of slide screws (7) washers (33) and
locknuts (8) and pin (66).
5. A gooseneck (12) fit on the mast with 2 slide screws (7), and two gooseneck plates (13)
cambered at the mast shape while fitting, and which will be riveted onto the mast with the pop
rivets (14) supplied.
6. A boom profile (15) which has been delivered in 3.20 meter (10’ 6”). It may be necessary to
re-cut the boom profile to length when fitting to match the expected boom length.
7. A mandrel (16) turning on bearings (17) fit on a bearing holder (19) at the rear end of the
boom, and on the drum-bearing holder (24) front, turning around a pin inserted in each of
the boom end fittings (22 and 23). When re-cutting the boom profile (15) to length, the
mandrel (16) should also be re-cut by the same amount.
8. A drum boom end fitting (22). It includes the drum-bearing holder (24) fit on the mandrel
(16): the drum being loaded with the furling line, pulling on the furling line while releasing the
mainsail halyard will rotate the mandrel (16), which will furl the sail.
9. 2 adjustable mainsheet bails (25).
10. A special boomvang (26). It is attached :
- to the mast by mean of a boomvang attachment, including an gooseneck (12)
attached onto the mast with 2 slide screws (7) washers (33) and locknuts (8) and two
gooseneck plates (13) which will be riveted to the mast with the pop rivets (14)
supplied. The boomvang lower end will be attached onto an articulation fitting (48)
rotating in the boomvang gooseneck.
- onto the boom with an adjustable boomvang hound (28).

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TOOLS NEEDED FOR FITTING
In all cases of fitting
nA tape line
nAn electric drill
nA set of drills
nA hack saw with a (new) blade with small teeth
nA file
nA pencil
nA plastic hammer
nA metric10 mm pipe-wrench
nA metric 17 mm pipe-wrench
nA dynamometrical wrench (1daN/m)
n1 set of Allen wrenches (supplied)
n2 clamps with a minimum opening 200 mm (7”)
nUniversal pliers
nA cutter blade (with new blades)
nA large sheet of paper with corners perfectly at 90° and adhesive tape
nSeveral small plywood or rubber shims.
nA pop rivet gun for 5 mm rivets.
Note : the plates to fit the gooseneck and boomvang attachments are 4 mm thick and
made out of aluminium. A convenient set of clamps with minimum 150 mm (6”) opening
should be used to bend them at the mast shape.
If the fitting is made on a standing mast
nA Boson’s chair
nSome short ropes of 6 or 8 mm (1/4” or 5/16”) diameter
Please purchase a 6 mm furling line and a ball bearing block to lead the furling line to the
cockpit.
II - PREPARATION
II.1 - UNFITTING THE HARDWARE FROM THE MAST
II 1 a - Dismantle the original gooseneck, as well as cleats, winches and winches brackets
on the mast, as well as any piece of equipment which would interfere with the fitting of the
new gooseneck and with the ability for the forward boom end fitting to rotate when the
boom will swing from one side to the other. Please see § III 1 b and drawing 1 for
dimensions of the new gooseneck in relation with mark « C » on the mast.
II 1 b - The original boomvang attachment should not be used, as the rotation axis of the
boom and of the new gooseneck need to be in line, which would never be the case with the
original boomvang attachment.
II 1 c - Dismantle the original feeder (if any) at the mast track entrance.
II 1 d -Check that the slide screws (7) supplied have suitable dimensions for the mast
track. If not, their width should be modified (turned, machined, grinned, filed) accordingly.
In all other cases please contact us.

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III - INSTALLATION
III 1 - DETERMINING THE HEIGHT OF THE GOOSENECK
III 1 a -To avoid any potential conflict between the boom and the cabin top, a bimini, a
lifeline or any other piece of equipment, please accurately mark the level of the lower edge
of the original boom. Please see drawing 1.
III 1 b - Check that the boomvang delivered with your system will make once installed a
minimum 30° angle with the mast and the boom. Should it not be the case, the position of
the new gooseneck must be raised on the mast in order to obtain at least this 30°angle .
Note pin to pin boomvang length : 1100 mm (5’ 87/8”) open / 1005 mm (5’ 33/16”) closed
III 1 c - Draw a line « C » on the mast at the level of the lower edge of the original boom.
Please see drawing 1.
III 1 d - Draw a line « B »on the mast at 267mm (10’ 2 33/64”) above line «C ».The line
«B » will correspond to the level of the upper edge of the gooseneck plates (13) once fit on
the mast.
III 2 - FITTING THE SLIDE SCREWS INTO THE MAST TRACK
III 2 a - Insert the head of the slide screws (7) into the mast track. The number of slide
screws you need to insert depends on the number of articulation brackets :
A- 2 slide screws are needed for the boomvang attachment. Slide these slide
screws down to the mast foot to later fit the boomvang attachment .
B- Slide 4 slide screws (7) into the mast track for the upper end brackets
(5).
C - Slide as many times 2 slide screws (7) into the mast track as the quantity of
articulation brackets (5) to be fit. See drawing 12.
III 2 b - Move the stacked slide screws mentioned in Band Cupwards on the mast above
the mast track opening, and temporarily hold them with adhesive tape to prevent them
slipping out of the track.
III 2 c - Slide 2 extra slide screws (7) into the mast track for fitting the gooseneck.
Drawing 1

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III 3 - FITTING THE GOOSENECK
III 3 a - Attach the gooseneck at the convenient height (§ III 1) with the 2 corresponding
slide screws (see § III 2 c), washers (33) and locknuts (8). Tightening torque must be 1
daN/m. Please see drawing 1.
III 3 b - Bend the aluminium gooseneck sideplates (13) with clamps to accurately camber
them to the mast shape. During bending please protect the plates from dings and dents.
III 3 c – Fit the gooseneck onto the sideplates with the rivets. Would the sideplates be too
long, they can be re-cut if necessary, keeping in mind too much length is always better than
too little.
III 3 d - Draw lead lines for drilling on the side plates (13). Press the side plates on the
mast with clamps ( please protect the plates with convenient means). There should have at
least 8 pop rivets (14) on the mast on each side plate (13).
III 3 e -Temporarily fit the gooseneck articulation (10) onto the gooseneck (12) as well as
washers 20 and 30, and tighten the counternut (30a) and locknut (31).
III 4 - ASSEMBLING THE LUFF PROFILES
Note: assembling the luff profiles will be easier flat on the ground.
III 4 a - Fit the luff profiles (1 et 2) together starting with the feeder profile (1) where the
feeder (3) is attached. The lower end of this feeder profile can be identified by the luff
grooves have been machined off. Please see drawing 2.
III 4 b - Completely insert a connector/articulation (4) at the upper end of the feeder profile
(1) . Please see drawing 2.
III 4 c - Fit and tighten the set screws (9) at the upper end of the feeder profile.
III 4 d - Fit a 2 meter long normal luff profile (2) onto the connector/articulation (4) which has
been fit as described above.
III 4 e - Fit and tighten the set screws (9) onto the luff profiles. Fit all the luff profiles (2) with
the same method except the last 2 meter normal profile. Please see drawing 3.
III 4 f -Hoist the above luff profiles column from the aft side of the mast by preferably using
the existing topping lift.
Caution: during hoisting check that the luff profiles are kept as straight as possible.
Drawing 3
Drawing 2

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III 4 g - Completely insert the lower end of the feeder profile (1) into the striped aluminium
connector of the gooseneck articulation (10) . Please see drawing 4.
III 4 h – Check fitting order of washers and nuts (3, 20 ,30, 30a, 31) onto the vertical stainless steel pin.
Please see drawing 4. Permanently fit the Nylock nut (31) with a 17 mm tube wrench onto the thread of the
stainless steel vertical pin. Fit the plastic cap (32) over the locknut.
III 4 i– Go to mast head taking with you:
•the 2 end brackets (5a)
•all the articulation brackets (5)
•the sheave box (11)
•all the slide screws (7) to be slipped up in the mast track, washers (33)
and locknuts (8).
Drawing 4

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III 5 - FITTING THE ARTICULATIONS BRACKETS ONTO THE MAST
III 5 a - Consider the 2 lower slide screws (7) stacked above track entrance.
III 5 b - Fit an articulation bracket (5) on the mast with these slide screws (7). Please see
drawing 5.
III 5 c - Fit the washers (33) and locknuts (8) onto the thread of the slide screws (7).
Tightening torque should be 1 daN/m.
Caution : during fitting the articulation brackets (5) onto the connector/articulations (4),
double check that the feeder profile is permanently and fully inserted in the gooseneck
articulation (10).
III 5 d - Continue fitting all the articulation brackets (4 & 5) with the same procedure.
III 6 - FITTING THE SHEAVE BOX
III 6 a - Slide up in the mast track the 4 uppermost remaining slide screws (7).
III 6 b - Temporarily fit the 2 end brackets (5a) and the sheave box (11) so that the rear
upper end of the sheave box leaves a minimum clearance of 20 mm with the backstay(s).
Please see drawing 6.
Drawing 5
Drawing 6