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                To Part One 
              To Part Tree 
              To Part Four 
              Part Two of Four 
              
                
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                  Remediating  a Pesky Case of Glue Failure. | 
                 
               
              Leg I: Sitka to WarmSprings Bay – September 2009 – 90nm1 
“A sailor's task is  to make the vessel in hand sail!” 
-- Paraphrased  from Tristan Jones 
Sea trials for SLACKTIDE began in Sitka, in September, en  route to Baranof WarmSprings for a winter care-taking job. This leg was  reassuring in most respects, despite a daunting beginning! 
We sallied forth in the company of friends and a  ghosting breeze. Eventually, a 10-knot interval (on the nose, of course), moved  us along on the slow side of OK, but we couldn't muster a tack. Uh-oh. But  first day and all... I thought we just needed to learn her ways. 
On our own, now, and a few miles on, we got  caught by a squall in a wind pinch between two islands; one of those natural  venturies. Probably the strongest 15 minutes of wind we've ever experienced on  the water. Swamped our dory (towed behind), but, deep-reefed in advance, we  slid through the squall in style. Pulled the dory out from under its load of  water and all's well. 
Except... what's that? Along the port side?  Did we hit some flotsam?? One of our copper plates, it turns out, has  peeled off the bottom to wing out to port, hanging by the angle-bronze  fasteners! Plates are spendy suckers, and one of them was hanging, as it were,  by a thread. Later inspection showed that at least one of our plates had gaped,  back in harbor (had weed growing on the inside face), explaining our slow start! 
______________ 
 
  1    This distance is tallied 'as the Raven  flies over water.' 
 
  Long story short: Every  freaking plate had come loose. Something about salt water, copper and  polyurethane glues (3M 5200 and SikaFlex) didn't take. Whatchagonnadoo? Fortunately, the glues left a great, waterproof gasket firmly bonded to the  plywood bottom. Between tides, we fastened all plates with bronze, ring-shank  nails and sailed on, sadder and but little wiser. 
  This set-back used  up all but a week before our job's start-date on 1 October. But, without drag  from sagging plates, we're really sailing... not burning up the water, but  moving right along, and able to tack into 20 knots and about four miles of  fetch (the most encountered on this leg). 
  And now we're slow  again, but this time thanks to light and flukey wind. Heading north out of  Sitka Sound, one threads a number of narrows and straits. They can incite  higher winds to riot, or baffle lighter winds into submission. Our SeaCycle had  yet to be mounted, so it's all sculling. 
  
Locally infamous, Sergius Narrows separate outer waters, opening onto the Pacific, from inside passages. Timing  differences and large tide ranges push current through three crooked and rocky  channels; up to 14kts on large spring tides. Storm surge across the Gulf of Alaska can jack that higher, yet. Twists, shoals and rocks  set up violent whirlpools and rips. Navigational buoys get pushed over and  under. 
Fortunately, it has  a back door; an island separates the marked, deep- water channel from Canoe Pass, used by smaller  fishboats with local knowledge. It even has a 'doggy door'; very shallow and  set off from Canoe Pass by an islet and  reef. That's our baby... least current closest inshore. 
  Our usual  method is to buck the last of a neap tide's foul current, make tracks through  slack tide and let the new, fair tide spit us  out on the far side. Timing is everything. Or should be... 
But this  time, we were an hour late arriving. Things looked placid, and we  decided it wasn't too bad... 
  Fair tide and rising (lifting off any rocks). Piece  o' cake! Of course, the problem is that once begun, there's no turning back. 
 
  Anke stood by the 18' push pole at the bow, ready to  push off either side. I kicked up the rudder to 45 degrees and raised the  leeboards. Forward into the breach. 
  Hmm... me thinks I hear a roar. First muted,  then not-so. Oopsie! Suddenly we're flying though at six or seven knots (as  measured by the Doppler Effect on our screams; EEEEEEE-YAAAAAH!). 
  Pretty thrilling, actually, but no control. Steerageway gone, pole  dangerous to use at that speed. We slid sideways, off the midstream bulge of  water, out of position, and saw toothy rocks, gnashing and foaming-at-the-mouth  within a foot of our pristine chines. 
  We'd barely pumped  a collective quart of adrenaline before we were through. Once back into deeper  water, the current gave us a contemptuous 360deg spin, then carried us on in  more friendly fashion. 
  Moral (one more time for  us slow learners): If late then wait! 
  The rest of this  leg was uneventful, even anti-climactic. Highlights included a 7nm sculling  stint along flat-calm Deadman's Reach, A little night beating in 15-20kts up a  relatively narrow channel. Some fun poking around while waiting for fair tides. 
  And then a longish tow. 
  Now I am averse to getting towed. But without wind,  we were going to be late for the job. A friend, starting several days after  ourselves, had kindly offered to watch for us along the route, and tow us if  necessary. We had commitments, so, for once, we accepted. Just shy of 40nm on a  leash... but good company is always a pleasure. 
  
The benefit was we got to see SLACKTIDE's wake while  being towed upright at 4.5kts (thanks to a 17hp diesel inboard driving a 28'  Hess Falmouth Cutter). Water rolls along her sides, then collapses  inboard as it clears the upward, aft curve of the bottom. No deep waves are  generated, though, as one can see in the picture, there is a fair sized bow  wake. 
 
  I'll jump ahead, here, to note that our theoretical  maximum hull speed (6.66kts) has not been attained under sail, either. In fact,  we readily achieve that 4.5kts, but work for more. In winds fresh and fair, we  can push to 5kts with intermittent, higher bursts. 
  Hypotheses: 
  
    
      - Our  S/D ratio is low – the snug, junk sail-plan is a first defence against sudden  williwaws, but doesn't develop full drive until Force 6 or so. 
 
      - By  Force 6, the water is getting choppy, and we are slowed by our blunt bow. 
 
      - Being  only lightly ballasted by copper and possessions, we're reefing by Force 6. 
 
      - Our  aft curve may be too abrupt for easy release of water, causing drag. 
 
      - The  long, mid-ship's dead-flat may be inherently slower than a rockered bottom. 
 
     
   
    
  
    - Note with interest that older sailing, box  barge designs, seen in profile, are blunt in the bow and easy at the stern. I  had thought this a variation of cod's-head-and-mackerel-tail, but now I'm less  sure. SLACKTIDE's aft bottom curve is relatively abrupt to maximize  displacement yet clear the transom corners when heeled. If these are  liabilities, I'd personally accept them in compromise on short hulls, but will  be testing models for longer hulls2. 
 
   
  Progressively  easing both ends eventually meets in the middle to produce full rocker, as  found in sharpie and dory hulls, eliminating the barge's mid-body dead-flat. I've  heard it said that some rocker makes for a faster hull, but note that  commercial barges have none. Certainly an easy release reduces stern drag. Entries  and exits are eased at the expense of displacement and ease of construction,  and extend a curve underfoot if living on the inside of the hull. 
  All in all, our compromises seem to have paid off. We  were braced for a total slug, but instead find our average speeds acceptable. Not  fleet but fit. 
  Thanks to our  friend, we arrived ahead of schedule in WarmSprings Bay. The job requires  living ashore, so we cozied up to a dock, unloaded her, and put her to bed for  the winter. 
  As you can see, we  put the extra time to good use! 
  
    
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      WarmSprings  – Good Livin' on the Ring of Fire | 
     
   
 
      
  
    - Poor Feller's Tank Test: Take two competing  models and trail them from either end of a spreader (plank, rod, pipe, etc.). Suspend  this spreader from the middle, as you would for a mobile, over a smoothly  running stretch of water (canal, ditch, tide... the smoother the better), with  the models trailing. See which pulls ahead and ponder the results.
   
This four-part  series of articles includes the following: 
  - Introduction to SLACKTIDE and Living Aboard
 
  - Leg I – Sitka to WarmSprings Bay
 
  - Leg II – WarmSprings Bay to Haines
 
  - Leg III – Haines to Tenakee Springs 
 
 
  Please  check back at this site for the rest of the series.
 
SLACKTIDE and other designs, along with more articles and FAQ pages, can  be found at   www.TriloBoats.com 
Dave Zeiger ©2010  
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