Back when I was wowing about a $100,000 design fee for a 52′ cat, the fellow who calls himself Ocean Cruiser correctly noted that if I were famous I could get those fees. Since I’m not, deal with it. He is right. And its not the first time I have been put in my place, or replaced by the famous designers.

It was back in the end of ’91 that I got a commission to design a 61′ trimaran.  It had all the makings of being amazing.  It was the first design that I had done in 3D CADD.  It had complicated organic NURB surfaces that needed to be trimmed to each other in 3D to understand how they worked.  Nobody was doing that back then.  Paul Steinart, Phd did the FEA work.  Reichard helped with laminates.  It was going to be amazing.  It would be light and quick, with only twin outboard power.  But the builders convinced the owner that I was a nobody, and if the project was to get the fame it needed, he needed a famous designer.  I hear it might have happened again.  Maybe some Alastra fame effect.

About the same time I did schematic design on a 40’something cat with undstayed mast.  I proposed that it have no main beam, but that the cabin slope 4 ways down like a tetrahedron to the decks.  It seemed to work.  I recall the owner was so nice and was from far away.  When Ricco visited, he told me he liked the design, but he needed a famous designer.  He hired Nigel.  I was pleased to later see that it was built, in NZ as I recall,  exactly like I proposed it.  I have not found pictures of it yet.  It had a name like Joseph or something, and was painted purple or chartruse or something.

My point is I understand the fame thing and agree that I just have to keep working and live without it.  No fame here.  Never will be.  Just working the problems.

I see that my 53/57 cruising catamaran now in the South Pacific, the Lil Explorers, has trashed a rudder.  I understand they have done a repair by now.  It looks in the picture like it absorbed a lot of kinetic energy.  Note to future self.  Keep the board down deeper than the rudder at all times.  Its much easier to fix.

That was a 3″ OD shaft with  .75″ wall on the plans.  It moved.  You wonder why I shake my head at those other designers who think 1/8″ wall is fine?  My boats are designed  to dry out on a tide flat with no rudder damage.

Nobody should build a boat outdoors. Do what I say, not what I do, or have done.
As in the picture, and its not really a boat, just built like one, notice the bog is dark. I use the slowest hardner in hot weather, but add graphite powder to make it dark grey or even black. That enhances a solar cure so I can be sure it will be sandable the next day. That also helps on cold days with a heat lamp.

Notice how the bog bits get darker as I get closer to completion.

Back at the 1986 Marine Applications of Composites conference in Melbourne, FL, the chairman, Ron Reichard took some of us on an after-hours tour of the materials testing lab.
The most visually informative samples that he had were a series of cored panels of about 2′ by 2′ dimension. They all had the same laminate; probably two layers of 34 oz triaxial each face.  They all had the same thickness of core, 1″ as I recall. 

Each of these had a bowling ball dropped onto it from maybe 18 feet? 

The balsa one was made of contour core squares and had the little squares blasted out the far side of the panel.  The impact side was destroyed. 

The crosslinked PVC one (Divinycel)  had its core sheared apart but the face skins were mostly intact.

The linear PVC (Airex, and later would be like Corecel) had a slight delamination in a small impact spot, only on the impact face.

For me that was a powerful visual comparison.  As Prof. Thiel used to tell us, “Compare simultaneous alternatives.”

As designer, I liked the previous one better. And they sailing reefed when sailing at all. Guess they have to use the big Cat engines more.  USCG certified for 100 passengers as I recall.

http://youtu.be/FcxD_4hzLVQ?list=UUjigikzWFcXr1OQWsg7vqqQ

I came across some pictures of a design that I did back in late 80s or early 90s. It is a 40′ cat that I understand is seen often in Mexico. Pantera was the first project where, at Bob Smith’s urging, I combined the hull deck into the hull lines as one entity. That took Prolines software to its limit of chords and made the section lines a bit chunky, but it was a big step forward.  And Prolines also upgraded as a result.
Bob convinced me that he was starving boatscum so real construction drawings were never budgeted.  It was strictly freehand work except for the lines.  Even the laminate design.  I learned later he is very comfortable.  So the only plans are on flimsey paper, if I still have them.

Foam/glass construction.

Designing for impact has many rules, but just as many exceptions. Here is one. Typically plywood/epoxy is thought of as very poor in resisting impact. And I agree, but here, as with many things, you have to sort out what the goals are.
Here is a picture of the 55′ Sierra Cloud after a jetski impacted it. The kid leaped off early.  The jetski was taken out through the hatch. This is clearly a poor impact resistance. Or is it? Larry did the repair quite easily with a 4 sided scarph replacement piece. The damage was little larger than the front profile of the jetski. 

Consider that if the boat had been built of an impact resisting material such as foam/glass, the jetski probably would not have broken the surface and would have bounced off of it.
But, I am sure the delamination area would have been at least a meter or two in each direction. That would have been a huge repair.  Since the cats can’t sink, breaching the hull is not the worst thing possible.  More on this topic later.

Talo is taking his beautiful D-32 trimaran out exploring the islands in what looks like the summer Baltic.

Another nice view of the 65′ Adventure Cat 2 sailing under Golden Gate Bridge.