Not all the sets have this yet, but according to people who use this detail, it supposed to be the best way yet to attach a window to a boat house. I have a PDF of it also that will be added when I get a chance. Or I can email it.
Alex’s Unstayed Mast
Its kind of a mini Sarabi.
We just got the bids in on the new carbon fiber unstayed mast for Alex’s KHSD 45 catamaran being built in Blaine, WA. It is what we call an aeroesque mast. Same general idea as the aerorig, but updated.
I’m sure the safety of these masts will make them the future of USCG certified sailing cats. The Coasties just need to see the FEA study to accept them.
World Cruisers
One of my earlier cruising cats was brought to my attention recently. I flew to Perth to build the hulls back in ’86 was it? They have cruised everywhere and it still looks great. Ply/epoxy in CM. http://www.boatpoint.com.au/boats-for-sale/boatdetails.aspx?R=9519130
“Magical” Catamaran Beams
Every couple of years I have someone ask me why my cat designs need to have aft beams. This occured again last month. They seem to have the tone that there must be a structural secret I just have not figured out yet. I did just get this picture. “Why can’t you do a beam like this? Ask them how they did it.”
People. Remember where I always say “with enough carbon and enough money, you can probably do anything you want to.”? There are limits. They probably think a sleek cat beam looks like this.
It actually looks more like this. The boat salesmen hide a beam like this so it will look thin or even gone.
That is compared to a standard beam. Like this…
So why don’t I catch up and do the flat beam? Remember how I always talk about efficient cats? Look at this.
The tools we designers use to compare beams are the moment of inertia “I” and section modulus “SM”. (assuming shear is satisfied) Suppose the regular beam is 12″ x 36″ by 0.1″ thick laminate. That regular beam has a SM of 99 in^3 (inches to third power) and a moment of inertia I of 2104 in^4.
In the horizontal mode beam, it only has a SM of 44 and the I is only 272 in^4. To get more strength and stiffness it must be made thicker and heavier. Even if the horizontal beam laminate is made 7 times thicker and 7 times heavier, it only has the same strength as the regular beam and still only a third of the regular beam’s stiffness. The flat beam boat vendors hope you don’t know or care enough to appreciate the difference. They can’t claim efficiency and still have horizontal beams.
Boatbuilding Materials Prices Going Up
Scott MacIndoe of Fiberlay recently noted that especially due to petroleum costs increasing, boatbuilders should expect sharp increases in boatbuilding materials in the next 6 months or so. If you are planning a project, get the materials now ahead of the curve.
everybody’s orders
I did just get the last of the orders out today from the backlog that built up when I was gone. Its in the mail.
Soft Board Control
I have usually always used blocks bolted to boards to allow the hold-down lines or the lift lines to function. In the same way that spectra wraps now can replace a track and car on the boom, I propose similar for a board. On a smaller board you can use a Harken C 8882. On a slightly bigger board you could use that part cut down the center and attached to both sides of the board. On big boards, I’m experimenting with a faired hole using high strength bog. I will see if teflon coating or graphite coating helps. I assume it will not work quite a well as a block, but be much cleaner.
New Pictures of JD’s 30 cat.
Some new pictures of Jim Dory’s 30′ cat have appeared at http://www.flickr.com/photos/jdory/5498545909/in/set-72157625973914417/
This boat was built and launched near Nome, AK. After it was launched, it was tied up in the harbor. During the night, in a gale, that barge broke loose and came to rest against it. There was damage, as you can see. But try to wrap your mind around how little damage actually occured. It was the fender for a barge during a gale.
KHSD Lake Victoria Ferry Launched
Earthwise Ventures launched unit #1 on Lake Victoria recently. The KHSD designed ferry is the first of 10 to be built. They have cylinder molded plywood/epoxy hulls and ply/core/ply epoxy house structure. This boat was built here near Seattle, disassembled and shipped in containers to Africa.
I’m pleased that it sits on its lines OK. They made the top house larger than designed, and were not concerned at all about weight. Unit #2 is underway and will be more elegant. The rest of the units will be built in Africa.
See http://www.youtube.com/watch?v=Y1SwCFtjoFY
Quick Boatsheds
I bought one of these sheds last year for $200. Moto-Shade. 10′ x 20′. http://www.moto-shade.com/Product_Detail.aspx?Id=73
At that website they list stores where you can buy it. The UV breaks the plastic fabric down in less than a year, but tech there told me the trick is to get a new one under the 1 year warranty before the year is up.
Its not big enough for a complete multihull, but many components can be built in one before the multi gets too big.