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Rabu, 18 Mei 2016

Heres what to give a sailor

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A few years ago some of my landlubber acquaintances asked me what they should give for Christmas to their friends who own boats. I responded with a column of advice. I’m not sure that it did any good, but I’m thinking there’s no harm in repeating it now. So here goes: 

TINKLE-TINKLE, TINKLE-TINKLE. The man with the kettle is reminding us to give, and give generously. This week there will be sailors all over the world who are receiving Christmas gifts from non-sailors. And it is to the non-sailors that this column is directed.

All right . . .  listen up now, you lot. What are the traditional gifts a non-sailor like you gives a sailor? I’ll tell you: a couple of battens for the mainsail. A stainless shackle or two for the bosun’s bag. A woolly watch cap for cold weather . . . let’s face it folks, I’m sorry, but this is not generous giving. The sailor in your life deserves better.

Now, heavens above, before you protest, let it not be thought that I am a purveyor of ingratitude. I believe as much as the next man that it is more blessed to give than to receive. I, too, believe it’s the thought that counts. I also believe that you should give according to your means and I am an ardent admirer of fiscal responsibility, thrift, frugality, prudence, parsimony and similar human traits that Mr. Roget reminds me of in his thoughtful Thesaurus.

On the other hand, the problem facing us today is that your average sailor does not want a silly hat or another mainsail batten to add to the pile of spares already cluttering the cockpit locker. What he really wants is a couple of gallons of anti-fouling paint at $150 a gallon. Or a 35-pound CQR anchor for $600. Or a new color GPS chartplotter for $800. Or a jib furling system for $2,000. Or a new diesel engine.

Yeah, wow, a new engine. That would please him no end. That would make a really good Christmas present. Ten thousand ought to do it. Fifteen, maybe if they have to build new engine beds as well. It sounds like a lot but it’s not really, honestly it’s not, when you consider the huge amount of joy it will bring. A really huge amount of joy. Honest.

It’s not too late to correct your Christmas mistakes. If you haven’t been generous before, you can be generous now. Tinkle-tinkle. Do your bit to make a sailor happy. Truly happy. Tinkle-tinkle.Give till it hurts. Tinkle-tinkle. I mean, really hurts. Tinkle-tinkle. On behalf of sailors everywhere, I thank you and wish you a Merry Christmas and a prosperous New Year. 

Today’s Thought
Money-giving is a very good criterion . . . of a person’s mental health. Generous people are rarely mentally ill people.
— Dr. Karl A. Menninger
Tailpiece
“What’s that you’re burying?”
“Oh, just one of my chickens.”
“Chicken be darned. That looks like my dog.”
“Yeah, right, the chicken’s inside.”

(Drop by every Monday, Wednesday, Friday for a new Mainly about Boats column.)

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Wood Decking

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The plywood under-decking was bonded in place with temporary staples to hold it until the epoxy hardened. Then the plywood was trimmed around the sheer and cockpit. The process was repeated with cypress planks, about 3/16" thick. Now the planks have been sanded. Finally starting to look like more than just the hope of a boat. I need to glass the stern, recessed transom, and splash pan before glassing the deck itself.

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Jumat, 13 Mei 2016

A Voyage to Remember

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                                                       A Voyage to Remember, Miami to Panama

When we were snorkeling in Maui recently, talk turned to snorkeling in Panama and our life there.  I recalled an exciting trip I took bringing a boat to Panama from Florida.  Our friends suggested that the trip was interesting and unique enough that I should record it on paper.  So my attempt follows.

When I was on active duty in the US Navy, 1966-68, I initially attended navigation school in San Diego.  The subject was interesting enough to me that I graduated #1 in my class, and continued to study available nautical references on board the two ships on which I served.  Spending many hours per day on the ship’s bridge deck for months at a time (crossing the Pacific twice, navigating the Mekong Delta, patrolling the Vietnam coast and Gulf of Tonkin, and cruising to Japan for maintenance) provided plenty of time for such review.  I became an enlisted supervisor in the navigation department.  Later, in 1976 while visiting Hawaii, I picked up a reference on Polynesian navigation techniques (We, the Navigators) to help understand how the early voyagers were able to find their way in the ocean’s vastness.  In late 1980, our family was living in Panama.  My assistant and her husband were buying a used 46’ trawler (single diesel engine) in Florida which they intended to bring to Panama to live and cruise on.  They asked me if I would act as navigator for the trip from Miami to Colon, Panama.

They offered to pay for my flight to Miami, which I declined.  If I were to do this, I wanted it to be from a sense of friendship rather than any monetary obligation.  I provided a list of the different nautical charts, references, and instruments which would be necessary for such a trip.  My assistant’s husband, Charles, was a retired US Navy diver who now worked for the Panama Canal Company.  He was to fly to Miami and spend one week examining and preparing the boat, including obtaining the necessary navigation supplies, before we left port.  He was one very tough individual and totally fearless.  He recruited a third crew member, Bill, who I hadn’t previously met but who seemed like a solid character.  It would be just the three of us on a quick voyage back to Panama.

I had talked to one of my patients, then employed as a canal pilot, who had previously been a Caribbean charter captain.  He gave me a route recommendation, which appeared reasonable, and loaned me his sextant.  I flew to Miami on a Saturday in early December, took a cab to the yacht basin, and was prepared to leave harbor the following morning.  Upon arrival, I asked about the navigational charts and references and was stunned to discover that none of the publications I requested had been purchased because it was now December 6 and the contained data was only good through the end of the year.  They were deemed too expensive to obtain for such a short period of use, but, without the sight reduction tables, the sextant was useless.  Also, only one chart had been obtained.  It was an overall chart showing Miami toward the top edge and Panama at the bottom edge.  With such a large area to cover, the chart lacked any detail of depths and features of the various coastlines.  Additionally, the trawler had only been maneuvered on various headings once to check the accuracy and deviation of the compass.  The boat was equipped with a radar set, but the range was only a few miles.  LORAN coverage of the southern Caribbean was lacking at that time, and GPS had not yet been invented.  This was shaping up to be quite a challenge, and I was glad I had some knowledge of navigation without dependency on instruments.

Checking on supplies, the trawler was almost empty with very little on board for ballast, just some groceries, a few tools, and our suitcases.  Our only refrigeration was a single large ice chest.  On Sunday morning, we set out on our adventure.  The first leg was to follow the coast of Florida southwest to Key West, then head straight south to the coast of Cuba.  The hurricane season officially ends November 30; we were now in December but encountering strong winds.  As we headed south from Key West we were headed into night, crossing the Gulf Stream with a strong current from the west opposing strong wind from the southeast which made for large, steep waves against our under-ballasted hull.  Forty-six feet may sound like a large vessel, but, on the open ocean, it is a tiny presence.  The strong wind created a surface haze of spray allowing very limited visibility.  Instead of an enclosed bunk, I had a bed to (try to) sleep in at night.  I tried to hold onto the bed, wrapping my arms and legs around the mattress while resting, but was completely thrown out of the bed once by the lurching hull.  Once I heard a scream from Bill, “We are going over!” as the boat slid sideways down the face of a wave with the rudder seemingly useless.  Fortunately, before we were rolled in a trough by the next wave, the rudder finally caught hold and the bow came around sufficiently to face it.  When it was my time to go on watch, I filled a paper cup with water and held it in my hand.  If I were to fall asleep, I would drop the cup, and it would be my alarm.  It worked.  Everyone needed what rest they could get; there was no asking someone else to take part of your watch.

We were glad to see the morning, but were now presented with a new problem.  Our large chart showed no detail of the Cuban coast.  As we continued south, we wanted to approach the coast as a navigational reference but not get so close that Cuban gunboats would escort us into port.  The solution was Polynesian navigation using cloud formations.  Distinctive cloud formations are found over islands.  Although we never actually saw Cuba, we followed its cloud formations west along the coast while staying offshore.

As evening set in, we were ready to jump off from the west end of Cuba toward Mexico.  It is an easy dead reckoning exercise (hard to miss Mexico) but it also meant re-crossing the Gulf Stream as it flows north.  We subtracted a few degrees from our compass course to allow for the current and set off into the night.  The next morning we sighted Isla Mujeres and pulled into port for refueling.  That afternoon we headed back out to sea with Cozumel to starboard and the Swan islands as our next intended waypoint.  Heading southeast, we encountered rising wind and waves from the northeast.  As the hull angled into the face of each oncoming wave, it was obvious that the "thump, thump, thump" sound of the big single diesel slowed significantly.  The engine was losing power.  Upon inspection it was discovered that sludge, from the diesel fuel we just received, was clogging the fuel filter.  The engine was being starved for fuel.  To clean the fuel filter we needed to stop the engine.  Then it was discovered that the alternator, used to charge the batteries, was not working.  The batteries were very low on electrical charge.  If we stopped the engine, it was doubtful that the batteries held enough juice to restart it.  It was time to change course and our plan.

We turned to run with the wind toward the southwest for a smoother ride and slowed boat speed slightly to match the speed of the waves and reduce engine load.  We shut off almost all electrical equipment to save the batteries, and Charles went down in the belly of the boat, holding electrical wires by hand on the batteries until the battery acid started to bubble, in an attempt to recharge the batteries.  Through the night we steered manually, using a flashlight to read the compass, and no running lights.  When it was my turn to lie in bed, I wondered what the future would hold if that engine stopped; what bit of shoreline or reef would the drifting hull crunch coral on?  Fortunately, the engine kept "thumping".

The next morning we could see some of the Bay Islands near the coast of Honduras in the distance off to port.  The wind and waves were still strong.  Charles thought that the downwind island was Roatan and suggested we aim for it.  I pointed out that if he was wrong, we would be unable to work our way back to any of the islands further upwind.  So we angled our course to port and headed for the nearest island.  It turned out to be Roatan.  The old wooden wharf was on the lee side of the island, allowing us to get out of the wind and motor quietly up to the dock (where I was to receive quite a surprise).  I was standing on the bow, dock line in hand, peering intently at the dock’s shabby state with substantial holes punched in its gray, wooden-planked surface.  I wanted to make sure that when I leaped to the dock to tie up, I didn’t put a foot through one of those holes.  Suddenly, a young black man came out on the dock, and his first words, in clear English were, “Hey, Did you hear that John Lennon was shot and killed?”  Here I thought I was in some remote place far from the beaten path, and I was getting the latest news in my own language!  Mainland Honduras inhabitants speak Spanish, but on the Islands they speak English due to previous British influence.  In Roatan we were able to get an alternator from a wrecked yacht which Charles and Bill then installed.  The fuel filter was also cleaned, and we had a good meal and rest at anchor before leaving the next morning.

We cruised east along the Honduran coast taking turns on watch.  The following morning when I came up on deck, I was immediately concerned.  I looked down at the ocean and saw churned brown water.  I yelled to Charles that we were in too shallow of water and were in danger of running aground.  He replied that the radar range he had taken indicated that we were a sufficient distance from the beach.  I pointed out that the radar was not being reflected from the gently sloping sand beach, but from a line of tall palm trees several hundred yards behind the beach.  We immediately turned out to sea until we were in clear blue water.  Later that day we passed Cabo Gracias a Dios which held a lesson for us.  The Cabo is the outlet of a major river marking the border between Honduras and Nicaragua.  A submerged tongue of silt, an invisible delta, stretches miles out to sea at this location.  You can be miles from the coast and still run aground in very shallow water.  Several ship wrecks stood as evidence.

From here we headed south and slightly east out on the open seas, away from the Nicaraguan coast, with the next intended waypoint being the island of San Andres.  The weather was now good, and we were able to troll and catch fish for din

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Senin, 09 Mei 2016

Vietnam Memories

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A coworker recently learned that I am a Vietnam vet and asked me for information.  That started me thinking about long past events, and I decided to write down one of my most memorable experiences, a trip out of the war zone to Japan.  The story is off topic; Ill post some Vietnam boat pictures to give the story context.  Above, top to bottom: 1. Wayne & Carl at a off-limits beach near VungTau.  2. A patrol boat of the S. Vietnamese navy.  3. The smoke of battle on the horizon on the Mekong.  4. Heavily armored landing craft used in close range patrols/combat in canals off the Mekong River. 5. A peaceful sunrise on the Mekong.  6. Downtown VungTau.  

September, 1966, I entered active duty with the US Navy.  After attending basic navigation school, I reported aboard the USS Askari, ARL-30, and was immediately assigned to help load armor plate and other supplies for our mission in Vietnam.  We left San Francisco in early December, stopping in Hawaii and the Philippines along the way, toward our new homeport of VungTau, Vietnam.  Most of 1967 was spent in the Mekong Delta.  I then returned to Vietnam aboard the USS Preston, DD 795, during the summer of 1968.  It was an important point in my life when I was on my own, deciding what was important and who I wanted to be.  No one cared whether hours were spent in a library or a bar; each person chose their own path.  It made for interesting observations and experiences.

When you were stationed “in country” in the combat zone for an extended period you would eventually qualify for “R&R”, rest and relaxation outside Vietnam. A friend, Carl Nixon, and I both qualified for R&R in June ’67 and both chose Japan as our destination. You were given permissive orders for the period.  “Permissive” meant that you were to find your own way from our ship upriver on the Mekong to Saigon to catch a flight and then find your way back upon return.  We got a ride on a boat downriver to the coastal town of VungTau.  As soon as we arrived we made ourselves scarce until the scheduled flight to Saigon had departed; then we reported in at the airfield.  That gave us an extra day on our own.  At VungTau, we often would walk some distance to an off-limits beach in a rocky cove served by a single café.  There we could eat lunch and play in the waves which were sometimes big enough for body surfing.  Later, we had dinner and a few drinks in town and, in the process, were joined by another Navy man who was headed to Saigon.  With curfew time approaching, the three of us visited a local hotel to get a room for the night.  The entry to the hotel featured a line of young women waiting along the corridor.  Carl and I politely declined companionship for the evening, but the other fellow bought dinner for “his girl” and she spent the night with him.

The next day we took a Chinook helicopter to Saigon; it felt like a flying bus. The military had leased an entire hotel with a barracks-type configuration for transient personnel in Saigon.  We didn’t wander far from the hotel that day, saving our funds until we reached Japan. We were anxious to get started and happily boarded a leased aircraft the next morning.  Arriving at Tachikawa AFB near Tokyo, we were given barracks-type beds & lockers.  This would be home base.  We relaxed and took a swim in the base pool.  Carl and I had lost our fellow Navy man, but picked up a crazy Marine on R&R.  Why do I say crazy?  This man had been in Vietnam for several years on back-to-back tours in the region of the North Vietnam border.  Every time his tour of duty was up, he would volunteer to stay longer.  Why would he do this?  Because soldiers don’t fight for their country; they fight for their buddies.  If he went home to the US, in his mind he would be abandoning his “band of brothers”.  At this point his unit had sent him on R&R, and then he was manditorily being sent back to the States.  They would allow no more extensions, and we could sense why.  He spoke casually about killing the enemy, had done it multiple times, and the enemy was anyone who would harm a US Marine.  It was questionable to us how he would re-adapt to civilian life.

Our Marine wanted to rent a cab and go to Yokohama (20 miles away) to drink Black Russians at a bar he knew.  Money meant nothing to him.  We decided to go with him and show him how to use the train system, saving considerable funds.  We found the bar, and drank a few Black Russians, but not enough to keep us from finding our way back.

The next day Carl and I set out again on a train to explore the area.  While on the train (think metro commuter line), I noticed a man reading a newspaper section which had a picture of a person water skiing on the back cover.  We asked where the picture was taken, and, although communication was limited, we were able to ascertain that the water skiing was at Hayama Beach, on the ocean southwest of Tokyo.  Looking at the train schedule, we realized that we could make the last train to Hayama that night.  Arriving at Hayama Beach well after dark, we walked down to the beach and discovered a party for college students was taking place.  We were immediately invited to join the party with the incentive, “We have more beer than we can drink.”  They were very friendly and spoke fluent English. We learned that water skiing was offered in late morning sessions and that a college music festival was taking place for the next few days. A little before midnight we rented a bamboo shack on the beach to sleep in.  Being in the Navy on a regular watch schedule I had developed an internal clock and was able to awaken at an early hour to get us on our way.  We needed to get up early to take the train back to our home base to clean up and get bathing suits and fresh clothes.

We arrived back in time to sign up for water skiing. This consisted of all participants lining up for mandatory exercises; then being transferred by boat to a covered platform moored in the bay.  The ski boat would come by the platform, each time picking up a new participant for a short period of skiing.  Water skiing was apparently a very new sport in Japan.  I watched people struggle to get up and then wobble around for a few laps before collapsing in the water.  This was the ocean, and waves were present, so their difficulty was understandable. Growing up in Nebraska, I had been skiing for 5-6 years using our family boat.  When it was my turn to ski, I quickly kicked off one ski to slalom and was able to perform enough tricks that a photographer was called out to the platform to take pictures of the action.  He had questions for my friend, Carl. The photographer couldn’t speak English, and Carl knew no Japanese, but they discovered that they both were fluent enough in Spanish to discuss water skiing.

Carl was an interesting guy.  Out of high school, he was accepted and enrolled at the US Naval Academy.  After a short time at the Academy he decided he didn’t like it and requested release. His request was refused until he contacted his Senator, who was on the Defense committee. He then quickly got his release from the Academy, but it wasn’t a release from military commitment. He was ordered on enlisted duty on our ship, the USS Askari, in Vietnam.  After release from active duty, he eventually moved to Morelia, Mexico, where he graduated from medical school and became a primary care physician in rural Mexico.

After skiing we discovered that a dance would be held that night.  Carl and I went to a local communal bath to freshen up.  Do you take a shower before stepping into the hot pool or afterwards? We may have done both. That evening we went to the dance. The music was almost exclusively familiar American rock & roll songs.  As we walked in, all the girls were in clusters along the far wall, and the boys were along the near wall to our left.  The dance floor was uncrowded. Adults were at tables toward the rear of the room to our right. We were the only Caucasians present. What do you do in such a situation?  If you are on R&R from Vietnam, you ask a girl to dance.

My attention was drawn to a girl standing on the edge of a group (pretty, relaxed, not engaged in the group chatter), and I approached her with a request for a dance.  After several dances she, Tamea, asked me to meet some of her relatives, who were seated in a booth toward the back of the room.  I learned that Tamea’s extended family rented one floor of the Hayama Beach hotel each summer for several weeks.  Tamea was a student at Tokyo University.  Later that evening, Tamea and one of her friends took Carl and me for a ride to show us the area.  We sat in back with a white-gloved chauffeur driving our dark limousine-type car and drove to a lookout point for a view of the surrounding area illuminated by thousands of lights.  After such hospitality, Carl and I requested that we treat the girls (okay, young women) to dinner the following day.

The next day we spent the afternoon listening to the music festival and talking with Tamea and her friend; one subject was explaining the lyrics and their context for American songs.  That evening we had reservations for dinner in a private room at the hotel.  As an E-4 in Vietnam, I was paid maybe $300 per month, but the exchange rate was 360 yen to the dollar, and we were on vacation.  We wanted to show our appreciation.  However, toward the end of the dinner, Tamea’s brother walked into the room.  Carl and I knew that was a “bad” sign.  Sure enough, they would not let us pay for dinner!  Look, we are enlisted US war-mongers from Vietnam!  Why are you treating us so nice?

I had agreed to shop for some speakers for a friend’s stereo system back on the ship in Vietnam before we went home (to Askari).  The week ended quickly.  Before leaving, I got Tamea’s address and learned that her father’s name was Dodan Kuruma. He was President of the Tokyo Buddhist Federation.  They lived in a suburb of Tokyo (Toshima-ku).  Her father had traveled extensively, to the US and Europe as well as throughout Asia, as a part of his responsibilities.

Sabtu, 07 Mei 2016

Sample Developable Design calculations

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In 2008 I wrote a short paper on a mathematical method of developable hull design (which is included in this blog, see entry of Dec. 2008).  I tried to keep it short and discuss only general principles, but some subjects are difficult to understand without providing examples.  Without any examples, I dont think it was very meaningful for most readers.  Recently the subject came up again, concerning the difficulty of developable design and the paucity of explanatory material.  Last night, I wrote a short paper concerning a stepwise approach and actual sample calculations involved in creating a hull shape.  The numbers used are from the runabout building in my shop currently.  The paper is not a comprehensive "how to" but hopefully will make the subject more easily understandable.

Sample computations for Developable Design


To illustrate the generation of many exact points along the chine curve, the following is a list of some coordinates of the chine at 7” intervals for the anterior chine of the hull I am now building:  (0, 0, 24.48), (7, 3.2, 22.56), (14, 6.3, 20.7), (21 ,9.2, 18.96), (28, 11.9, 17.34), (35, 14.4, 15.84), (42, 16.7, 14.46) ,.…. until (119, 28.8, 7.2).  This series is generated from the parabolic curve Y = 28.8- (119- X)squared / 490 and also Z = 0.6(28.8-Y) + 7.2 and is valid for values of X between 7 and 119. 

Where did these equations come from?  I want a boat about 6’ by 18’, so I picked a length of about half that which I could evenly divide into 16 segments [more segments = more accuracy]; 16x7 or 112” will suffice, next add a short straight 7” segment onto that.  Have you ever noticed that when you bend a batten, the curve does not extend all the way to the end of the board?  At the batten end there is no fulcrum to apply torque.  Thus, last few inches have no bend unless confined along its entire length.  So I always add a straight segment at the end of every curve.  A 6’ beam gives a 36” half beam; minus some width for flare of the topsides (4”) and an allowance for a chine flat (3.2” at maximum point) and you end up with 28.8” chine beam which is 25.6” of camber in the 112” length and 3.2” of offset along the 7” straight end segment.

To create the forward keel projection, I most frequently use a parallel projection.  A conic projection, with the apex of the cone forward, will create sharp curvatures in that area.  It may be what you want, but it will also be hard to plank.  A conic apex amidships will give a mild curve at the keel, if that is what is desired.  The parallel projection has a controllable curvature and is easy to calculate.  We already have defined a 28.8” chine beam, and picked a 7.2” deadrise to go with it [based on estimated displacement].  So deciding on the slope for this parallel projection from chine to keel only involves selecting an X intercept from the maximum chine point (119, 28.8, 7.2).  The further forward we select this point, the more pronounced will be the forefoot of the keel with sharper curvature.  I chose a point 52.5” forward of maximum chine beam.  52.5/7.5 = 7; 28.8/7.5 = 3.84; 7.2/7.5 = 0.96; thus we have our slope, X: Y: Z=7: 3.84: 0.96 which coincides with the 7” segment intervals.

Now all anterior keel intercepts can be calculated to define the keel.  At the keel, Y=0, and we solve for X and Z.  X@keel= X@chine- (7/3.84)Y@chine and Z@keel= Z@chine– (0.96/3.84)Y@chine. Aft of the point X=119”, the keel is straight and Y=0 & Z=0 for the keel.  After finding the shape of the keel, we next move on to the shape of the transverse frames below the chine.  To calculate transverse frame shapes below the chine, the same slope or ratio is used.  We set X = 14, 28, 42, etc., or whatever other frame locations desired, and solve for Y and Z.  For every 7” forward we project a chine coordinate, the Y dimension will decrease by 3.84” and the Z dimension will decrease by 0.96”.  Simple math creates the entire shape of each frame.  Just connect the dots.

Creating topsides with some flare to the bow, transitioning into a tumblehome stern, seems to be best accomplished with a conic projection forward, linked to another conic apex further aft to create the transition, then a parallel projection extending aft to finish the tumblehome contour.  Conic projections involve finding a third point on a line give two defined points.  Rather than discuss an entire design, I will list selected apices and show sample calculations.

The apex of the first cone was selected at X, Y, Z = (56, 39, 70.2).  This will give a bow angle which matches the forefoot of the keel and provide moderate flare to the topsides not to exceed a 6’ total beam.  A sample calculation would be to calculate the Y and Z intercepts at the frame location X = 98 for a line between the apex and the chine coordinates (119, 31.9, 7.2).  The calculation is Y = 39– (98- 56) (39– 31.9)/ (119– 56) = 34.27 and Z = 70.2– (98– 56) (70.2– 7.2)/ (119- 56)= 28.2.  The relation is that the change in any one coordinate of a point on a line is proportional to the change in any other coordinate.  Since we choose our X intervals, we can then find Y and Z.

When calculations are complete for X between 0 and 126, we select a second apex (91, 35.5, 38.7) which lies on the ruling line, halfway between the first apex and the point of maximum chine beam (to the outside of the chine flat) which is (126, 32, 7.2).  This new apex is then used to calculate points aft to the chine location (189, 32, 7.2).  From there a parallel projection is used with the slope 7: 0.25: 2.25 and defined points every 7” along an extended chine equation to X= 294.  Although the actual chine ends at X= 213.5, the extended portion will determine the shape of the tumblehome at the stern when projected forward.  As more curvature is included in this extended curve, the tumblehome will also increase.

The entire shape is not yet designed, but sequence and type of calculations needed should be understandable.  The results, when finished, are full-size measurements in three dimensions with fair curves and excellent accuracy using simple tools.  Enough offsets are generated that all you have to do is connect the conveniently-spaced dots.

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Selasa, 12 April 2016

En route to the GPS of all trades

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I WAS WONDERING what people might be giving their boats for Christmas when my eye fell upon an old 2008 advertisement for a Garmin Rino 530HCx. I have never seen one, but the Garmin company is famous for GPS navigation instruments and the Rino seems to be a departure from the norm.

For a start, it can’t spell its name. It should be Rhino, not Rino. It has two antennas that look vaguely like the horns of a rhinoceros. In Africa, game poachers often saw off a rhino’s horns and sell them to customers in the Far East, who grind them down into a powder that reputedly has aphrodisiacal powers.

Frankly, I’ve never understood how that works. You swallow some powder and suddenly women look attractive to you? What? Who needs rhino powder? Didn’t they always look attractive to you? But wait . . . I’m getting carried away here. Sorry. Back to the Rino:

It probably isn’t a good idea to saw off the Rino’s antennas, no matter how much of a boost your testosterone needs. I suspect something won’t work if you do that. Something on the Rino, that is.

The interesting new direction this hand-held GPS was taking was evident from its attributes as listed in the advertisement. Besides a color screen that shows where you are on a chart, there are two built-in radios. One is a Family Service Radio, a glorified walkie-talkie. The other is a General Mobile Radio Service radio, a rather more sophisticated mobile transceiver for which you need an $85 license.

In addition to GPS and two radios, the Rino has a barometric altimeter. This tells you how high you are getting, which is very useful in a season of sequential Christmas parties. There is also an electronic compass so you can find your way home if you are too high to read the GPS screen. In addition, there is a built-in weather radio that informs you what kind of storm struck you on the way home.

There’s more, but I’m sure you can see which way the new generation of electronic gadgets is headed: One GPS does it all. I can’t wait to see what they add to the next generation of GPSs, but in case any Garmin people read this column, I’d like to suggest some additions to the new “omnibus” Rino GPS.

It would be real nice, guys, if you could add a night telescope so people can find their slips after dark. And how about a few rocket flares to help the search-and-rescue people find lost sailors? A small bar would be very welcome, just a little one, of course, perhaps with miniature French maids dispensing cocktails etc., to the shivering bodies in the cockpit on the midnight watch.

I suppose it would be too much to expect a modest galley with a European chef skilled in confiture and baguettes. No matter. Most sailors I know would settle for a GPS with a fish-and-chips dispenser.

Today’s Thought

I find the sea-life an acquired taste, like that for tomatoes and olives.

— Ralph Waldo Emerson

Season’s greetings

I wish you all a merry Christmas, a happy Hanukah, and best wishes for whatever celebration you choose to observe at this time of year. I wish you peace and tranquility to calm your soul, and I wish you fortitude to face life as she presents herself in the New Year.

Tailpiece

“Good grief, what happened to your face?”

“I coughed.”

“But you don’t get your teeth knocked out if you cough.”

“You do if you cough in your friend’s wife’s wardrobe.”

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