THE BUILDING OF THE COMMEMORATIVE J 100
A progressive reporting by Simon Ballantyne
Queries on these pages welcomed: email me
Prior to the Association's 2001 A.G.M. it was decided to run a raffle fund-raiser. The 100th J hull was to be the first prize and a ticket I took on my son's behalf won! He lives in Jakarta so, "Dad, if you would please?" Being the 100th hull, it deserves to be commemorative; so a blow by blow construction diary follows. (Providing it doesn't get too lengthy!)
PAGE ONE ~ Cradle - Hull - Inwales and Deck Beams - Keel - Rudder Post - Rudder
PAGE TWO ~ Rudder to servo linkage - Servo/Rx/Battery tray - Winch mount - Pre-decking details - some deck fittings
PAGE THREE ~ gluing the deck - Deck Fittings - Painting
PAGE FOUR ~ Vangs and Kicking straps -
PAGE FIVE ~ Radial Jib Fitting - A Cheap Gooseneck and a Not so Cheap Gooseneck
Late October
About
four or five hours spent at making the first essential - a boat
cradle. Most of the time was spent filing and sanding away at the
hull support uprights in order to get a good fit (allowing for
padding)against the hull sides. Before fitting side rods a good
undercoat was painted on - otherwise the cradle is to be left
unpainted until after the model is finished, as it is used for a
building cradle once the model leaves the gluing
jig. The cradle was made out of low grade 12mm ply and follows the
well established pattern/plan typical of most Js.
October 31st
Cut
out from 4mm ply, bow and stern blocks and bevel sides to fit hull.
Locate and pick up gluing jig; some repairs on same. Bow and stern
blocks glued in. 10 x 8mm inwales ripped from salvaged kauri, some
bevelling and trimming to fit. Slow-setting Epiglue is the
recommended adhesive as it has good gap filling qualities - however
nothing beats close fitting of pieces, and that is a time consuming
exercise. NOTE: When gluing anything to the
glass fibre hull do take time to skim off the parting glaze on the fibre
glass with 60
grit sandpaper and then key the glass with a few strokes of 40 grit.
Otherwise even the best of glues will fail!
November 2nd
and 3rd
Glued
the Inwales to glass hull ~ a very messy job with glue all over
hands - try springing a one metre pre-glued strip into place between
two recessed points and holding down the middle as well! Upper edges
of glass hull do not register exactly with jig surface - proud
inwales will need a lot of sanding down afterwards. It is not
neccessary to pre-shape the inwales but a little bit of chamfering
fore and aft makes for an easier finishing job later on. It pays to
run masking tape below the hull inner gluing
area and around the edge of the jig ~ you don't have to be so careful
then about glue over-runs - peel off before glue sets. A little
candle grease on the clamping screws will prevent any glue seizures! Some
time spent considering beam configuration and winch and hatch placement.
3/11 ~ A bit concerned about the starboard inwale - the glue hasn't hardened completely, must have got the mix wrong! Port inwale is fine. Anyway I rebated cutouts for the crossbeams and glued them in place. Hope things are rock hard tomorrow - King Plank to fit and then hull can be removed from the gluing jig.
November 4th and 5th
4/11 ~ Fitted and glued cross beams and king plank - this is where
the disc on the Dremel belt sander comes into its own in accurately
angle facing the beams tofit. Glue on Stb inwales has set hard. [Note
how the hull is identified on keel plate as "J100 901" - 901=
Sept 2001]
5/11
~ Hull removed from gluing jig - set up on cradle and with
progressively finer rasps and sandpapers brought the proud timbers of
inwales and beams down to the glass gunwales.
November 6th
Levelling off the inwales, beams and planks, is taking a little time - amazing how a straight edge can pick up bumps and hollows that depart from the natural shear line! A good idea to hang a plumb line over the stern centre point to ensure the boat is sitting vertically, sighting to the rudder face on the keel - can then use a level to make sure hull timbers (and later the decking) are truely horizontal to the vertical.
November 8th
Trimmed up the lead keel today and attached it to the hull.
Unscrew the two studs and then carefully true up the lead surface
presented to the hull (note that the hull bottom is not actually dead
flat). 
Offer
the keel frequently to the upturned hull and check for its vertical
alignment in line with the hull's rudder face, and fore and aft for a
good fit to the fibreglass. Obvious lead bulges can be rasped off at
this stage. NOTE
(March 2004) - DO NOT REMOVE TOO MUCH LEAD, FILL THE GAPS INSTEAD!
THERE IS AN ADVANTAGE IN KEEPING ALL THAT EXTRA WEIGHT BELOW THE C.
OF G.! Refit the studs and if the aft one
appears to be too long for the application of a socket driver, cut
off 
a
calculated length (you won't be able to use a spanner inside the
hull). Markout and drill oversized holes for the studs. Mask off the
hull by about 2mm, and rough sand the face as a key for the glue. If
needed, enlarge stud holes to allow accurate registration with the hull.
Apply a liberal amount of epiglue to the hull keel face, the lead keel face itself, and to the lower parts of the studs and present the hull on to the studs - gradually tighten the nuts, not forgetting the extra ballast weight and the washers, and constantly check alignment fore and aft, and laterally. When satisfied remove from vice and leave upside down for glue to set (check alignments again) - peel off masking tape at this stage.
On the photo (left) I hung a plumb line from a rafter and used it to check the vertical alignment of the lead keel against the rudder face on the hull as the rasping of the mounting face progressed.
November 9th
A good glue set overnight - today spent with rasp and surform shaper fairing the lead keel into the hull lines. A good idea not to rush this job - take two or three days as nothing looks worse on a model yacht than a detectable demarcation line twixt keel and hull. Most keels are well cast and need minimal filling of pit holes and depressions but a degree of patience and perserverance will be needed as the keel is slowly blended in to the flow of the hull lines. Automotive two-part 'bogg' is ideal as a quick setting filller for the cavities. It is best to take several goes at bogging, sanding down between each - several thin applications of 'bogg' are better and harder than one great big blob! Even when all looks well, spray on some undercoat and as soon as you sand it down you will see more high spots and gullies appear. A must workshop accessory is a vynyl covered hard sponge squab on a timber base - great for sanding small fragile articles upon and great for turning and twisting a J hull. I have one which is about 30cms by 50cms which has been knocking around the workshop for about twenty years. Clamped on the workmate it is a great table upon which to lay the now quite heavy hull without fear of stresses and strains, or of scratching.
Picture:
- For removing great amounts of lead with good control, nothing
beats a small surform shaper dragged slowly and positively over the
offending bumps. The Sandevik file in the middle is flexible and is a
great finishing file; it is large but easily controlled, and its
flexible nature does wonders in following and smoothing the keel
contours. The Sandevik file on the right is a rigid "shark's
tooth" rasp on one side and a smoothing file on the other - does
a good job of trueing up any straight faces.
November 10th & 11th
Still working at fairing the lead keel into the hull lines - it is not as symetrical as I thought and even with all care there is loss of vertical alignment because of a significant bulge in the port side of keel casting particularly at the rudder face - slow and patient work. 11/11 - A lot of time today will be spent doing repairs and maintainance on Js 45 and 50, and getting J90 out of storage.
November 12-16th
Don't worry - work is still going on - just interrupted with family commitments - the proud owner of J100 has returned home from Indonesia for a five day break - busy sailing J90 before he deeds it to me and gets J100!
November 17 - 19th
Finally satisfied with moulding the keel lead into the hull lines. It involved plenty of filing, sanding, bogg filling, and even for a clergyman, swearing!
Cut out rebate and fit keel rudder 
trunion
on the keel - use S/S screws - this is where it is handy to have a
metal turning lathe - the trunion was machined out of 6mm sq brass
rod and it was an easy matter to measure the angle and drill for the
rudder pivot. Some time spent in marking out, drilling and elongating
the hole for the rudder tube extension at the top of the keel rudder
face. Rudder tube is from 9mm aluminium arrow shafting with plastic
bushes top and bottom to take 1/8" S/S rudder shaft. It will
eventually be packed with 
vaseline
as a lubricant and water seal. Once the keel trunion is fitted then
the rudder post can be set in place accurately by passing a long
length of 1/8 rod that can be aligned between the keel trunion and
with the centre line on the deck beams. This rod will eventually
become the rudder shaft. First gluing sets the tube in place - As the
rudder post, it will be braced later at the top with a ply triangle,
and at the hull exit some bogging will be required to fair the post
into the hull lines. NOTE: When gluing in rudder
post and using a rod for alignment - do thoroughly grease the rod
with vaseline first because no matter how careful one is, there will
be the ineviatable glue bondage between post and shaft!
November 20th
A simple 3ply brace was made and shaped to sit easily without
forcing between the hull and rudder post and be glued in place - its
exact dimensions are not critical and it is positioned on one side
only to allow plenty of 
unrestricted
space through which the tiller arm may swing on the other. Its
purpose is to counteract any twisting movement the tiller movements
might cause with the possibility of damage to the hull exit of the
post and subsequent water-tight integrity. In the photo the top
bush has been removed to allow the brace to drop over the rudder
post. One of the problems of using the preferred adhesive,
Epiglue, here is that its slow setting time will preclude any further
work until tomorrow! However will work on the tiller arm and its
swivel linkage to the steering servo. Can also begin to rough shape
up the rudder before it is glued to the rudder shaft. NOTE
~ don't forget that before the deck is glued down all hull timbers
will need to be thoroughly painted with polyurethane varnish to make
them water and mould resistant!
November 23rd
Not much work over the last two days - rudder to servo linkage was built up but can't be finalised until the servo/winch bearers are in place and rudder servo fitted temporarily.. After much doodling and thinking I have decided to place the winch below decks and lead the sheet forward to emerge at the bow and up and be coupled to an elastic tensioner. All this has been in the mind, and to date I have only fitted the cross bearers for the winch and Rx/Battery box. Photo will follow in due course. The rudder servo will be hanging on its own mini bearers from the side of the hull. (See servo tray detail on Page Two)
November 26th
The rudder blank supplied was thinner than
the width of the keel rudder face so I ripped a 15mm plank off an old
bit of oregan and fretsawed a blank to the official profile. A
1/8" router attachment on the Dremel soon saw a slot to the
required depth in the blank's leading edge so that it would sit
properly on the rudder stock. Then with progressively smoother files
the blank was brought to the correct shape. It is normally sufficient
to key the rudder stock rod with a few strokes 
of
a coarse file and glue it in the slot. Some builders however like to
cross drill the rod in a couple of places and fit 1/16" brass or
S/S pegs to ensure the rod will not twist on the rudder. What I have
found to be a good practice is to fit either a turned collar or a
washer at each end of the rudder stock. Once the glue is set then the
leading edge of the rudder can be rounded off to allow it to turn
against the keel face. When gluing the stock
into the slot on the rudder, double check lengths and keep glue off
the remainder of the rod! The slot can either be
conpletely filled with glue or a piece of 1/8" x 1/8"
timber inserted and left proud on the leading edge to be sanded in
later when the glue has set. .....GO
TO PAGE TWO
I would be most glad to respond to any queries that builders of the Canterbury J might care to direct to me - left click the button below.
