Commander #155 'Mephisto Cat'

[Rico]

Ed - I do believe that the boat pictured in the link is a Bristol 27 (or similar) - not a Commander. But it is a good picture never-the-less...

C-227 Thanks! When I am out there, I wear a full-time grin!



The Sail Track

If you saw my query in the 'Jib Track placement' thread (http://www.pearsonariel.org/discussi...read.php?t=283) , you know what my most recent project was; I am happy to announce that I have installed the sailtrack. It seems like a simple enough task. -Just drill some holes and screw them in - as someone who should know better put it...


This is where I started:

I had more questions than answers and I was all over the place... - could come up with reasons for all sorts of angles for the track... (The only part I knew was the location of the Genoa track - the purple line on the rail - which remains un-installed! - not needed yet due to the Bay's consistent summer breezes...)



Having sought tons of advice from racers, members of this board, and pretty much anyone within earshot about these &^%$% tracks. - I SLOWLY learned what the important bits were AND most importantly whats bits to ignore. - At least enough to think that I did... which allowed me to start thinking about drilling holes.

I also learned a bit more about sail geometry and trim, and started to get information enough to proceed and determine the location for installing the jib track. - Credit must go to Ed Ekers for turning some key lightbulbs on, on the topic!

I am happy to report that it appears that I got it pretty darn close to correct... I am very happy with the results. I am using twin-sheet track cars on these tracks. My sail trim ability is much, much improved! (See pictures in post above with tell-tales pointing straight aft from top to bottom of sail...) And all sheets run free and clear of everything.

As I previously predicted I would, I've repeatedly told myself: I wish I'd done this sooner!!


I started by reinforcing the Winch bases - for good measure - as the loads experienced by the jib sheets with proper sail trim are expected to be greater than those seen to date with the use of the cabin-top tracks...

The winch reinforcement went something like this:
Session 1: Remove winch bases, Re-drill for oversize holes in deck, fill with dense epoxy resin, grind epoxy filler flush with deck, add matching gelcoat color-coat on top, redrill final holes.
Session 2: Install winches @ coambings, Find previously made aluminum backing plates that remained un-installed from before, set in bedding compound, Install winch bases, seal, re-fasten, wait a couple days and tighten.

After finally deciding on what should be the desired location for the 4' length of racing jib track, I proceeded in a similar manner as described above.


The track installation was essentially as follows:

Pre-work: Add Polysulfide to track sections as bedding compound/sealer, buy aluminum plate 3" x 3/16" x 10'. Sand, prime, & paint backing plates, Cut plate to size, add 'base' polysulfide bedding compound to backing plate accounting for noticeable peaks & valleys and let cure, find previously bought fasteners.

Session 3: Measure at least 20 times (accounting for adjustments for possible sail trim variations, track car locations, OTHER potential future sails, sheet routing, curvature of the interior's surface (where the backing plate goes), AND bulkhead location), Mark track fastener locations, ponder all of the above, then close eyes, cross fingers, and drill locator holes.

Session 4: Re-drill for oversize holes in the deck, clean out balsa core bits and prep holes, fill with dense epoxy resin, grind filler resin flush with deck, add gelcoat color-coat to match.

Session 5: Redrill final holes, cut backing plate again to fit/straddle bulkhead, drill holes in backing plates, paint backing plates - again, test plates for bedding compound profile & fit.

Session 6: Install track with additional (fresh) bedding compound, Find fasteners, loose the fasteners, fasten track to deck & install backing plate underneath with fresh polysulfide, pack tools laying everywhere, vaccumm bits of dust everywhere. Wait a few days for fresh polysulfide to cure, re-tighten fasteners,

By the time I finished on Session 6, it was late & quite dark... It was all fuzzy... Don't remember getting home... The next day I went to the marina to find a track on deck - (and there was another similar track on the other side of the boat!)

Picture 1: The oversize holes in the deck. I am happy to report that there was nothing but BONE dry balsa in all the holes... - You never really know what has been going on for the last 40 some years!

Picture 2: The backing plates with offset holes to better match the interior profile. -The Angle cut on one end of the plates is to match the angle of the bullkhead. Note the initial polysulfide application to compensate for peaks & valleys and as pre-cured bedding. I like to provide semi-cured bedding on initial installation of any load bearing surface underneath a fresh layer immediately before installation.

Picture 3: The final results.

Picture 4: Picture of the backing plate in its final location. (3 more bolts are beyond the bulkhead) Note that the little lampshades are now in place after being in a box for about 3 years. I'm told we look 'more civilized' now...

When doing the Gel-coat, I re-did the clear epoxy coating on the forward hatch. The stuff does not like the sun and although the Gel-coat still looks GREAT, the hatch is looking a bit dull in spots... I'm thinking I might gel-coat it gray or white.... Hmmm....

[Commander 147]

I want mine to look similar when I get done with it. (like I will ever get done with it, after all it is a boat).

Are you using a block at the aft end of the new tracks behind the track car to create a fair lead to the winches? It is hard to tell from the pictures but it looks like if the track car was forward to much it would cause the jib sheet to rub against the combing boards.