Index

Jib Deck Tracks.

INDEX - Deck Track, Extend a Track, Bend Techniques, Cabin Mount,

NOTE:  "There are limits to increasing boat speed or arriving at your upwind destination sooner by pointing higher.  A high performance keel boat can do this for one reason only, keel shape.  The deep keel is a foil that generates lift as it "pulls" through the water.  Total lift is a squared function of forward speed: double the speed, quadruple the lift.  An SJ24 keel is much more efficient upwind with its high aspect ratio deep keel.  However, the SJ23 has a keel stub so it can be easily trailer launched.

The trick to getting the most pointing performance out of the SJ23 is to drive the boat hard to maintain speed through the water, which allows the keel stub to generate more lift, which leads to less leeway.  You can aim the boat as high as you want and sheet the beejeezus out of the jib, but on the SJ23 with the stumpy keel, compounded with the flat centerboard, the underwater foil just stalls, lift goes in the toilet and the boat ends up going sideways (leeward).

I sheet my working jib to the rail, lead from about the shrouds.  For Genoa sheeting, I trim it so the leach is about a foot or more off the spreaders.  For comparison, I trim an SJ24 jib to 2 to 4" off the spreader.  The goal here is to drive the boat hard with an open slot to let the sail plan breathe, not stall the keel and minimize leeway.  In addition, the SJ23 has relatively little rocker and sailing lower and fast means you don't pound into head seas, which can stop an SJ23 dead.  When in doubt, foot off.  If you have speed through the water you have way more control options to make something happen."  Glen Moore.

You can determine the optimum sheet angle by drawing a straight line from the middle of the luff, through the clew to the deck, allowing for the height of the block.  This position is usually good for mid range winds for the particular jib.  Since you now have a "middle point" for the track you simply have to allow for about a foot fore and aft for lighter or stronger winds.  Remember to allow for the height of the block when positioning the track.  Do this for each of your jibs and you will quickly determine the position and overall length of the track.  The SJ23 manual, Tech Tip H08 (Sail Setting Guide), also has suggestions on where to place the sheet block for the optimum angle.  At one time Panache's deck track was equipped with a Merriman doublewide block, so it was possible to set a new jib sheet on the go without releasing tension on the working jib.  This is great for swapping a hanked on jib on the go.  Coincidentally, a single sheet slides easier through the double block.  If you install a single block on the track then use a spring under it to keep it standing.  This keeps it from flopping against the gel coat, which is also quieter when sailing in the "doldrums", and keeping it standing means the sheet will run easier through it. 

INSTALL A DECK TRACK (1995) - The 4' long 1" wide (1.2M x 25MM) track on Panache (shown at right) is through bolted to the deck.  The holes are sealed with epoxy to prevent wood rot and the track is sealed with Sikaflex.  A backing plate of solid tapered oak is installed on the ceiling.  It is just thick enough to encase the mounting nuts thereby preventing a nasty scrape on your skull.  Wow, is that ever miserable!  There is no point in sealing this oak, although it is stained to protect the wood against moisture.  I can't remember how the track mounting nuts on Banana Split (below left) are covered but I sure wish Panache had that full 6' length to position the block precisely for each size jib. 

The track on Banana Split, an SJ23 in Portland, was bent horizontally (along the difficult dimension) to follow the curve of the cabin.  Forming the track horizontally is best performed with a three wheel bender that has two idler rollers on one side with an opposing third middle roller on the opposite side.  As the track is drawn between the three rollers, the force (screw or hydraulic) from the middle roller bends the track in a smooth curve.  There's art involved in doing this job and it pays to have some experience.  Metal benders of this type are usually available in a specialty machine or aircraft maintenance shop.  Sometimes you can find an old guy who just happens to have one.  "This happens more often than you think.  All you have to do is ask.  Helps to have a coffee in hand." 

TRACK SPECS -  Anodized Aluminum, 1" wide, 1/8" thick lip, 1/4" x 1.5" flat head mounting screws spaced 4", stop pin hole 1/4".

EXTEND A DECK TRACK (2024) - I've also seen long deck tracks consisting of two sections, one added later when the requirement changed.  But then shipping a long section of track has always been difficult and therefore more costly, so its understandable that a person would extend a track.  "It wouldn't be the first time that someone offers me free stuff and the gears start churning on how to merge this treasure in a seamless fashion.  I've been there and done that, so I don't blame you.  But at least make it look intentional and ask for a beer if someone wants to hear your story."   I had hoped to form the mechanical parts at Panache's winter storage location and seal the deck holes with epoxy on the water.  Unfortunately the extensions arrived after launch which forced me to do the fabrication and the installation on the water.  Difficult to say the least, considering driving, weather, fitting parts, forgetting things, etc.  Aaarch.  Thankfully I never dropped anything in the drink. 

Design Criteria - In 2024 I bought a full hoist 120% jib for which I require a 6' long deck track to position the sheet block further aft for the correct sheet angle.  I also need a longer deck track when I furl the 150% genoa and have to move the sheet block forward to the deck track.  I'm not sure about loading a sheet block that is positioned at the end of a track.  I'm reluctant to disturb Panache's existing 4' water tight track, replacing it for a single 6' track.  So for these reasons I added a 2' extension to the aft end of the existing track. 
- The 2' extension is curved to follow the cabin wall for appearance and to retain free deck space.
- The track ends are "keyed" together to prevent side movement.  Keying is far superior to a butt joint where either track can move relative to the other.  The key only needs to be ~1/8" deep. 
- As a precaution to high track loading, the track joint is reinforced with an overlapping wood backing plate, secured with a mounting bolt on either track.  The joint is shown below. 
- To prevent marine growth the slight gap between the tracks and the bottom of the track extension is sealed to the deck with butyl rubber. 

Shown at right is the track extension temporarily placed parallel to the cabin wall.  This view helped visualize the installation to foresee any problems.  The forward portion of the track extension will be bent slightly to facilitate a smooth joint.  The car slides easily across the joint without binding, a benefit of the loose fit that most cars have.

I made a cardboard profile of the cabin side wall which was very useful in forming the track in the garage.  That is also where I cut the key in the end of the extension.  The other half of the key was cut on the deck using a Dremel tool and point files.  Very tedious time consuming job.

Cabin Wall Consideration - At one time I seriously thought about removing the 4' deck track to install the (4+2)' tracks as one unit against the cabin wall.  See Cabin Wall Mount below.  This would require the 4' track deck holes to be filled with epoxy and the deck painted with Kiwi Grip to protect the epoxy against UV.  That would have taken too much time out of my sailing season especially if it rains.

Upon further investigation I rejected the cabin wall installation since the space under the window is not quite wide enough for the oak backing plate I have inside Panache.  I use the plate to recess the nylock nuts to prevent the installation from looking like a 1920s tractor.  If it doesn't look good it isn't sellable.  Always keep that in mind.  Ultimately, the bottom rail of the curtain is mounted below the window and I'm not about to eliminate the curtains. 

Parts:

• 2 Anodized aluminum tracks, 1" wide, 1/8" thick lip, bevelled screw holes spaced 4", stop pin holes 1/4".

• 14 10/24 (5mm) x 1.5" flat head SS mounting screws.

• 14 SS nylock nuts.

• 14 SS flat washers.

• 2 backing strips of teak.

Track Bending Techniques: Bending the metal track to form along the cabin wall makes this installation look good and prevents stressing the fibreglass.  Bending along the short dimension is easy but along the long dimension can be difficult.  It must be done with a uniform radius matching the curve of the cabin.  The tricky part is to bend both tracks equally since your eye can see the parallels.  You definitely have to use your creative juices for this task.  After successfully bending a sample with Merlin's Compact Bender there was nothing left to do but give the track a nudge.  Here goes nothing.

I step bent my track extension using the floor mounted Compact Bender shown at right.  This is not exactly the correct use of the tool, but if you are careful it works.  It required less effort than I thought due the leverage of the 3' handle with a built in 2' extension.  But I did position the pusher pegs close together for the most mechanical advantage and the smallest bending radius.  I pushed the handle with my hip to have lots of control and to closely monitor the bend.  None of the anodized finish was damaged, which surprised me.
I made extensive use of my cardboard cabin wall template and stopped bending as I approached the final curve, preferring caution over bravado.  As it turned out this was the correct decision with the tracks fitting perfectly along the cabin wall.

Bending can be accomplished in several other ways:

• Roll the track through a 3 wheel metal bender.  I thought these might be easy to find but not around here anymore.
• Step bend the track while clamped in a bench vice might be possible.  Pull it sideways with a pipe slipped over the protruding section.  Use a long pipe for more control.
• Step bend the track between a stopper peg and pull it around a form.  The closer the peg and the form are, the easier it is to bend.  You must get creative to mount the bending hardware.
• If a twist should form in the track, use a vice and a long crescent wrench to torque the track back to flat. 
• If you don't have the skill for this, take the track to a machine or welding shop. 
   
• Bending the track over a sand bag is not recommended due to the lack of control.  But it does have the advantage of protecting the finish against the bag.
• Pounding the track over an anvil risks damaging the surface and for that reason should be avoided.  It would definitely get the job done quickly though!  Remember appearance.
   
• Final bends being scrutinized by Merlin.  Apparently he approves.

Installation:

• This installation is a tedious job that demands attention to detail.  Seek perfection or you will never be satisfied.

• Drill and seal track deck holes using the technique described in Tech Tip G08.

• The easy way to accurately transfer the track holes to the backing strip is to clamp the track on top of the backing strip and drill through the mounting holes.  You can do this well ahead of time if you also label each piece.

• Tightening the track screws is an "orangutan issue".  It demands two people.

PORT	STARBOARD
	Fig 1, (left) - The track was outlined on the masking tape then held inside the outline to be used as a drill guide for the mounting holes.  Step drill through the deck; 1/8", 1/4", 3/8", to prevent tear out of the interior fibreglass skin.  The drilling debris was caught on a towel laid on the settee.  Nice to work clean.  Next was to seal the balsa core with epoxy.    Fig 2, (below) - The cabin ceiling was washed with acetone prior to plugging the holes with Gorilla Tape.  As a result there was no epoxy leakage from any of the holes I filled.  All holes filled to full depth without a void.  The Gorilla tape left no adhesive behind.  Easy clean up.
Fig 3 - The G-Flex epoxy cured over a longish lunch.  The masking tape did an excellent job of protecting the deck from wet epoxy.	Fig 4 - The G-Flex cured for 2 days after which I sheared off the epoxy mounds with a sharp chisel which also removed the masking tape.
Fig 5, (below) - The top of each hole was bevelled slightly for sealing with butyl rubber.  Its doubtful I did this for the 4' track installed many years ago but they haven't leaked.	Fig 6 - My initial design called for an aluminum plate to lap the joint for all the strength that could impart.  Ultimately I decided the plate installation was too complex to implement and difficult to install given Panache's distance from my shop tools.  It was going to require delicate recessing that would be too difficult and time consuming with hand tools on the water. I mulled over this decision for quite some time.  But since track joint is already fastened by 2 track mounting bolts through the teak backing strip that straddles the joint to strengthened it, I decided this to be sufficient.  The pen points to the position of the track joint.  However, I may install the plate at end of season. The track extension is sealed with butyl rubber for its entire length, just in case I have to remove it.  Why make things more difficult than it has to be?
Fig 7 - Port track sealed and mounted.	Fig 8 - Starboard track sealed and mounted.
The last of the screws were set and the nuts tightened on the longest day of the year.  How iconic. It feels really good to have a water tight deck again given the threatening weather I've had. Next is to hoist the 120% jib.  Need to find a good boat photographer.  They are scarce.

INSTALL TRACK ON CABIN WALL (SJ24 & SJ28) - Besides the potential for water leaks and wood rot in the deck core, the other problem with a deck mounted track is that the sheet block is in a perfect place to catch bare toes.  (I hate that!).  I realize you shouldn't walk barefoot on deck, but there are times when it's simply too hot to bother with shoes.  In this case, sandals with straps over your foot are a good alternative.  Make sure they are the type that will stay on your feet to preserve your toes!  Flip flops are a no no.

Anyway, a friend suggested I install the jib track on the side of the cabin, just below the window.  This is the factory technique on his SJ28 as shown at right.  Note that the turning block is hanging and the deck is almost clear.  Shown on the left is an SJ24 with a similar installation. 

With this technique it is possible to reinforce the track on the inside of the cabin by through bolting it to a backing plate or grab rail.  A shoulder height grab rail in the cabin is very useful in rough weather or to dry clothes after the rough weather! 

The cabin wall mount is a favourite location of many designers to achieve close jib sheeting.  If I had to do it over again for Panache, I might install the track on the cabin side wall.  However, it must have a backing plate of aluminum or wood inside the cabin to distribute the load.  This requires a lot of extra engineering.  If you want to hide the nylock nuts, cap the nylock nuts and the aluminum strip with a thin wood strip.  Get even fancier and you can install a grab rail over it all.  Makes a nice neat, functional installation that is easy on the eyes and hands. 
 

Return to Tech Tip Index. . . . . . . . . . . . . . . Have a Question?