The Americas Cup

The Americas cup is one of those sailboat races that has been going on for a long time and happens again and again at various intervals.  Seeing as it involves large sailboats, only the very rich can compete, albeit with hired crews.  This year the race or part of the race is happening in San Francisco Bay on which I live and so the news about it reaches me.  I have nothing to offer on the merits of the race but it did happen that the Swedish race team is working out of an aircraft hangar close to my own modest boat shop and so on the way to work or going home from it, I see the boats that compete in the event.  So I want to offer some photos of the Swedish boats because I find the boats interesting.
By the way, I understand that the current crop of boats are a short version of what will be in the final competition.  And all the boats were built in New Zealand by the same builder to the same specs so that he race is about who has the best crew and not about who has the best boat.

 This is one of the two Swedish boats tied off to a buoy in the Seaplane Lagoon.  In the background, one of the maintenance hangars from the Naval Air Station days.

 The boats and the sails are moved in and out of the water by a crane.  They are not that heavy as boats go, around 3000 pounds. 

 Here is the boat itself, without its rig.  Dagger boards are in their retracted position.

 And the Americas Cup logo and Swedish flag.

 The boat has a wing and a jib.  The wing is symmetrical about the center plane unlike an airplane wing which is usually flatter on its bottom face.  

 And there are the Swedes, out on the bay doing their stuff with their support boats motoring behind them.

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Plastic kayaks Pros and Cons

Recently, a friend let me paddle his plastic kayak, a boat that he was quite fond of.  I never turn down an opportunity to try out other kayaks and so I got in this one and paddled away.  The boat looked very pretty with its white bottom and yellow top and was still new and shiny, but the bow seemed too blunt and pushed too much water, creating much noise in the process. It wasnt a flaw that you would be likely to notice just by looking at the boat, but it was readily apparent once you paddle it.
I reflected on this and came to the conclusion that I couldnt be the only person that noticed this problem with that boat.  But given that the manufacturer had already invested in a mold, he probably had to sell a certain number of boats before he could recover the cost of the mold.  Only after that point could he consider making a new mold.  The longer he held on to the old mold, the cheaper the cost per boat would be.
And that, in a nutshell is one of the major problem of mass produced boats.  The thing that makes mass produced boats cheap is that they involve a minimum of labor.  Make a mold, and once you have a mold, you can squirt plastic into it and out comes one shiny boat after another.  But the mass production is a good thing only if you have designed a good mold.  The manufacturer had better built a number of prototypes and tested them for good design before committing to a mold.
If users give the manufacturer feedback on design flaws, he really cant do much until his first mold is payed for. And this is more of an issue for small manufacturers who, lacking deep pockets need to pay as they go.
If you buy a custom boat from an experienced builder, you pay more than for a production boat, but you are also less likely to be a victim of design flaws.  I suspect the custom builder gets to build a lot more boats and gets a lot more design experience than the builder of production boats.  I might be wrong, of course, given that I dont really know what credentials production boat designers have or whether production boat manufacturers even have experienced designers on their teams or just hire consultants or copy someone elses designs.  If anyone knows, Id like to hear from them.

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Deck Hardware and sail report

July 20, 2015

Sorry for the lack of updates.  But, I wanted to go sailing this summer and decided to put the computer on hold in exchange for a full focus on finishing the boat.

Deck hardware was installed with backing blocks, and polysulphide sealant.  It is amazing how many little screws, washers, lock washers, bolts, and nuts are needed to install the cleats and blocks.  This necessitated no fewer than 5 trips to my local hardware store that has a very good selection of stainless steel hardware (amazingly out of $10 lockwashers).  The only tricky part was the installation of the centerboard downhaul and uphaul, as this was a new type of system I needed to learn as I went along.  In practice, it works well, but necessitated shaving down the aft part of the floorboards that serve as a platform up front so that the lines would run free.

I also needed to move the boat onto the trailer, which meant the 18 workskiff needed to come off.  Using levers and jacks, I was able to lift the 1000lb clamming skiff off the trailer and then slide the Core Sound 17 onto the trailer from the building form using old rugs to protect the finish.  

The CS17 fits perfectly.  

I still need to add the self-bailer, and the docking hardware, and oarlocks, but it was time to get out on the water and see how long it would take to rig and launch.  

30 minutes to step masts and rig.  could be 15 without mistakes. 

As you can see from the photo above, there was very little wind, but the boat moved along even with ghosting conditions.  

photos of the launch. 

https://www.flickr.com/photos/41024536@N02/sets/72157655720562508

July, 21,2015

Went out to Hopkinton State Park.  It was much better with winds 5-12kts.  The boat sails beautifully, and points very well.  I was very pleased with how easy the boat is to control and how well it responds to gusts.  I felt in control at all times throughout.  

Sorry, no photos, I had my hands full.  

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Plywood the other boat skin

One of my ongoing research areas is what to cover a skin on frame boat with other than industrial fabrics sealed with modern sealants.  Yes, there are animal skins, and I know that people have covered their boats with cow hides, but you see, we live in an industrial society and the imaginary scenario I am creating for myself is that the factories have shut down and one has to operate as boat builders of old did, that is, to find boat building materials in their immediate surroundings.
Perhaps we have to broaden our definition of skin on frame a bit and allow a boat where the skin is the main structural material and the frame is of secondary importance.  Enter the plywood boat.
In my case, not a boat exactly but a plywood pool punt.  The main idea was to not spend a lot of money.  The secondary idea was to provide a stable lounging platform for a pool in an environment that is too cold for swimming for most of the year.

Here is the punt under construction.  One sheet of plywood formed the bottom, another formed the sides.  Height of the sides was just a bit under 16 inches.  Early trials established that 16 inch sides were too high so I trimmed them down to 13. Perfect. The sheets of plywood are screwed to battens inside the punt for additional support.  Water proofing of the screw holes courtesy of 3M 5200. Water proofing of the seams was done with a layer of glass adhered by epoxy. 

Initial trials also established that the sides of the pool abraded the fiberglass that I sealed the seams with so I added some wooden bumpers at the corners and some skid rails at the bottom for dragging the punt in and out of the pool. Then a few coats of gray paint from a five gallon bucket that a friend was tossing away, or rather, giving away. And oh yes, we realize that the pool is greener than it should be. 

The same day we launched the new improved punt we also ran into a small futon and some quilts that a neighbor was discarding.  These are now lining the bottom of the punt.  Very comfortable and stable to boot for someone used to sitting in narrow kayaks.  Sometimes it is OK to trade speed for comfort.

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Why Build Your Own Kayak

A friend of mine recently posted a picture of a customized car from circa 1970 Houston, Texas.  What struck me about the photo was that the owner of the car clearly wasnt satisfied with the amount of chrome that designers back in Detroit were putting on cars at the time, so he took matters into his own hands and added chrome to a level that he felt was appropriate.

And this same sort of urge, not the urge for more chrome, but the urge for more cool is what led me to start building my own kayaks. It was not about money, it was simply the desire for a superior esthetic over what commercial manufacturers were capable of delivering. Others may disagree.  Many prefer the look of shiny plastic.  I prefer the cool of skin on frame.

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Why Are Sea Otters so Cute

The sea otter post on my blog is the all-time most popular. No other post even comes close. I guess there are a lot of people out there who want to look at pictures of sea otters. Sea otters are probably the cutest animals there are, cuter than pandas even. 
What makes them so cute? I think that the key to sea otter cuteness is the fact that they look like cuddly baby animals even as full grown adults.  I think its all that fur that makes them look so cuddly.  And they lay on their back and they stick their furry paws up in the air and the fur makes their eyes look like little buttons and that black furry nose, so cute.  Makes you want to just pick them up and squeeze them.

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Fiberglassing Completed

With the sounds of the Hallelujah Chorus still echoing in my ears, Im happy to say that fiberglassing work on the Utility hull is finally completed. Ive added a second layer of epoxy to the whole thing, and the next step will be to sand it down smooth in preparation for painting. Until then, at least, its nice and shiny.

The Next Problem?
For planing boats, the bottom of the hull is supposed to be flat along the aft 1/3 of its length. If its not flat, the boat will likely tend to porpoise (bounce up and down at the bow) at higher speeds.

For an 11-foot boat, 1/3 the length would be 3.67 feet. Checking the bottom of my boat with a 48" level, Ive found that the aft 36 inches is fairly flat. However, in the aft 48 inches, there is a noticeable hook that is about 1/16" in depth. So the unanswered question is, "will it porpoise?" Since the bottom of the hull is not as long the top, and the final 36 inches is flat... perhaps itll be okay. Perhaps not. Only time will tell.

Even though I dont know for certain just yet, Im tempted to go ahead and add a wedge to the bottom of the hull while its still upside-down and easily accessible. Ill think about it.

The gap between the hull and the level shows a hook of approximately 1/16" depth.

Progress on the Zip
Ive got the transom knee for the Zip built. While the plans call for a 1-1/2" wide knee (two 3/4" plywood parts laminated together), Ive added additional 1/4" pieces on either side to widen the knee to 2 inches. It should be plenty strong. 

Transom knee for the Zip.

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