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Tom Lathrop

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Posts posted by Tom Lathrop

  1. Why is there a reefing  line anyway?  I insert the tip of the sprit in the loop at the reefing cringle/point just like as at the clue.  The sail shape is then controlled only by the snotter and no other lines are needed. 

     

  2. I'm afraid that your Lapwing has had some serious issues in either building or maintenance in its earlier life.  Since you bought it in 2012 and it has not been stored in any exposure to the elements since then, it had a pretty short lifetime to incur all that damage.  Probably no more than 5 years and likely less than that.  Good plywood just doesn't go bad that fast even if it was only painted.  I'd venture that someone owes you an explanation. 

     

    I'm the owner/builder of the original Lapwing which has been simply protected by a tarp cover for its life of a bit less than 10 years and it has no such problems at all.  Its very distressing to see this kind of damage on a S&G boat and even more-so on one so young. There is a ply/glass/epoxy Windmill sailboat sitting alongside Lapwing that has not had the level of protection as Lapwing and it does not have anything approaching this kind of damage although it is 24 years old. 

     

    I think that at least a new DB trunk is in order

  3. I very much doubt that anyone could detect a difference in drag/speed in slight rounding of the transom edge on a Bluejacket.  On a very small boat the percentage of drag increase would be greater than on a boat, of say 16, feet but still not measurable at normal speed for our boats. 

     

    On a racing sailboat, I might sharpen the transom bottom edge and foil trailing edge but not anywhere else.  Some of the difference that might be seen is probably due more to perception than reality.  Feeling good about the potential of your boat may be as important as any actual advantage. 

     

    On a Bluejacket, I would go for the small radius edge that will hold whatever surface you put on it.  It is far more rugged and you will never see any difference in fuel use, speed or anything else.  All liquids hate a sharp edge and will pull away from it.  The technical term for this tendency is called "surface free energy" or surface tension by the layman.  This is what makes it so difficult to cover a small nail hole or pinprick hole from a bubble in paint. 

    • Like 1
  4. I was suspicious of that and maybe we should have foreseen the possibility of salt water puddling at this point.  It is one of the issues with using non anodized aluminum for masts.  A drain might have prevented the failure but, who knows?  May need to rethink how stress relief is engineered.  Just having a thicker mast section would not have failed without any reinforcement but weight, especially aloft is always a bugaboo.

  5. The weakest point of any unstayed mast is where it exits the deck or,in this case, at the connecting point of the tabernacle. What you are looking at at the stub on Southern Skimmer ( if my memory is correct) is an insert made with a double layer of carbon weave over a foam mandrel.  The break appears to be at the end of the insert which was inserted to reinforce and distribute stress away from the exit from the tabernacle.  Since even a double layer of carbon weave is not nearly as stiff as the aluminum mast, it was thought that this was a good idea.  The fact that the greatest load would be at the bolt through the mast on the tabernacle, it seems strange where the break occurred.  Has the aluminum mast suffered any physical or chemical damage at this junction?  I would like to see the result when they get home.  This mast has survived some severe loading in rough conditions since it was built.  Temporary running side/back stays are used when the spinnaker is flying.

  6. I guess I should enter this discussion.  On the Bluejackets, I expect that both decks and pilothouse tops will have people walking on them at times.  The foredeck especially may have the occasional jackbooted dockman jumping on it.  Therefore each was designed to suit the expected loads that would be placed on it.  I specify 1/4" ply for the top layer but 3 or 4mm is adequate to handle the tension loads on the bottom of both.  Spacing of internal ribbing (laminated 3/4" beams) is also closer in the foredeck for the above reasons. 

     

    In Jeff's application, there will not be any need for supporting heavy or concentrated loads on the structure so it can be designed and built with this in mind.  I would choose 4mm ply for the top and bottom skins and perhaps less interior structure as well.  The foam is not only for insulation although that is a plus.  The blue or pink 3/4" styrofoam also offers rigidity and additional support for the thin skins.  The more curvature that is built in, the more rigid the structure will be.  Depending on the area of the hardtop, wind loading may be a factor and the mounting must be strong enough to handle that when the top is extended.

     

    If Jeff sends me an email, I can email a drawing of the BJ pilothouse top with notes of recommended differences.

  7. Chuck,

     

    After some reflection, I remembered that Sikkens says that it is porous and able to breathe through to the wood underneath.  Over epoxy, that would not be possible so that may be why they say to coat only bare wood with it.  Anyway I have gotten better results with Sikkens over bare wood than any other product.  Of course, if I want the best looking finish and know that it will not be exposed to the elements all the time,  I use Z Spar Captains or Flagship.

  8. 4 hours ago, Chas231 said:

    I have some wooden parts made for the mast I'm working on. I coated the wood with clear epoxy, but they will be outside and need UV protection. Can Cetol be applied over epoxy?  Instructions on the can say to remove all previous coatings. 

    Chuck

     

    Chuck,

    I cannot answer the question, but it is probably best to follow Sikkens directions.  I have used both polyurethane and varnish over epoxy many times with good results.  When I redid LIZ's rubrails last year I used SIkkens Window and Door finish since it gave me really great results on our mahogany front door that is in full sun half of he year.  (The door is on the website and gets redone only about every 4 to 5 years)  I stripped the poly over epoxy with a heat gun and think this will be longer lasting. 

     

    The Window and Door variety does not have any of the orange tint that some Cetol has.  It does not have quite the depth look that fresh varnish has but after six months or a year it looks much better than varnish and then lasts for a few years more before demanding to be redone.  It does take a lot longer to dry and stand up to abuse but I can live with that for its good qualities.  I have to order that particular variety of Sikkens as the local stores only handle the marine versions.  They may offer the same good results but I stick with what  I know.

     

  9. 33 minutes ago, Beacher said:

    To Graham or anyone else familiar with the ICW along the planned route:  what percent of sailing v motoring was expected? Friends who have done the Great Loop through the area in larger sailboats describe it as a motor route.  I'd like to know if a small sailboat makes it into a sailing route. Thanks.

     

    If your boat is not rigged to be easily converted from motoring to sailing and back again, it will likely be a motor only trip.  Most "snow birds" wind up motoring only whatever their original intention and many will not even remove the sail covers.  It depends on the individual as well as which part of the ICW you are considering.  Maine to Sandy Hook to Cape May and Delaware is best under sail with the Chesapeake good for sailing.  From there all the way to south Florida, opportunities for sailing are less available but still, some have done it all the way under sail. 

  10. 1 hour ago, Hirilonde said:

    Winter backpackers don't use butane as a fuel for cooking.  It doesn't work well, if at all when it is cold.  Propane works better.  White gas is best of all, but not as safe or convenient to use.

     

     

    .That is why you keep the butane can in the sleeping bag with you.   He ran out just short of a gas stop at Mclellanville.  I always fuel up at Isle of Palms where he is now.

  11. 2 hours ago, Alan Stewart said:

    Yesteady evening Graham reported 41 miles completed. By his "current" calculations he needs to do 35 miles per day to reach Tampa Bay I'm time. Graham has yet to show me how to do "current calculations" but I think it must involve dragging your pen and paper in the water. ? 

    He was able to sail part of the day but the winding course made for inconsistent help. Fortunately he caught the top of the tide and was getting a good push south much of the time. 

    Good answer Alan.  Just compare the log speed of the pen and paper to the GPS and the difference is current.

  12. As for the ICW, my favorite is the area from Charleston to Beaufort and also Waccamaw River area to Georgetown to McClellanville with side cruises on the east flowing rivers and estauraries all along the way if you like to get off the main path.  Georgetown is a very nice old town and worth a stop.  Don't be put off by the paper mill.  Some other sections of the ICW are heavily stocked with homes, docks and no wake signs.  You need to locate fuel and other necessary stops before taking off as they are sometimes not close to each other especially between Charleston and Beaufort.  Beaufort and St Helena Island area is full of interesting waterways and islands.  Tidal range gets more significant the further south you go and attention should be paid to the tables.

  13. The route Graham is currently taking in the ICW is one that I have done many times in both power and sailboats.  The consistency of Carlita's progress would indicate that he is under power 100% of the time.  Average speed of today leaving from Little River, SC is about 3.33mph, which looks reasonable for a 17' boat and a small 2.5hp motor.  As the weather warms, he should be able to get in more time but the speed in the ICW may not increase much.  Favorable winds will help but north wind means cold with northwest wind probably the best this time of year but none are in the near forecast.  Probably not a good chance of getting outside in the ocean soon if the forecast is right. 

    I made it from within a couple hundred yards of where he spent Friday night to Georgetown, SC in one day on Jan 10 in a 35' sailboat.  We started as soon as we could see and finished well after dark in Georgetown.  Not advisable but we needed to transfer crew there.  Probably ran more than 12 hours when daylight is far less.  Will probably take him 3 days for the same route.  Similar conditions of cold and rain which it looks like he may see.  Good food and some warmth available in Georgetown.  My last trip down Winyah Bay leaving Georgetown could best be called nasty but at least dry. 

  14. Paul,

     

    I did not choose to have W10.  When we forgot to opt out one time last year, MS automatically loaded it on the computer.  I am thinking of having the guru come over and put me back on W7 which can be done..

  15. OK, HUZZA,  HUZZA,  hats thrown in the air and lot so noise. 

    Frank provides us with a really inexpensive, well free, site to hunker down in the boatyard with others similarly afflicted.  Unlike another well know site where posting photos or illustrations is an exercise in frustration, Frank has made this site super easy to do that.

    Carry on!!:D

    • Like 1
  16. When I got  my first 15 1/2 foot sailboat in 1966, one of he first thoughts was to mount a small motor to get about when the wind did not blow.  One way or the other it has never happened that a motor has been on when sailing, although there have been some longish paddles.   Found out that a whisker pole is more effective as a paddle than you might imagine. 

     

    The BRS was excellent as a motorboat or sailboat and was used both ways.  Everyone's situation is different and its clear that some will find great utility in having a small motor kicking along back there.  A BRS is designed so that a separate mount is not needed but the others will need some kind of provision for mounting.  On some, a notch to one side with a bit of reinforcement will suffice while others will need a more involved installation.

  17. I haven't talked to Graham about it but will make a guess.  Carlita has considerably more sail area than the standard CS 17.  Unless the CB of Carlita was increased in area to balance the side force from the greater sail area, it may not be quite large enough in a blow.  Easiest way to do this while maintaining the same interior room is to make the CB longer.  Carlita may (likely) also have squeezed in more sail area than a standard CS17 MK3 for racing the EC.  Could possibly also have weight deeper for more righting moment.  Just speculation but will hear what Graham has to say.

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