Saturday, September 24, 2011

Weighing in

It's been just about a month and a half since I cut the first wood for the boat. I spent the better part of 9 months designing in Rhino 3D and I am up to saved version 103. I have 12 ama iterations and about 6 of the main hull. All that and I'm still making major changes to the boat. Such is boat building.

A few days ago I removed the temporary frame that held the sheer line in place while I was installing stations. I've been anxious for that because it meant I could weight the hull. Drum roll.....62lbs as it sits. That is minus a couple of bulkheads, stringers, cabin sole, seats, cockpits, hatches and of course epoxy coating. It's heavier than I had hoped but not a death sentence. She is still on track to be significantly lighter than any production multihull of this size and power.

Below are the visible epoxy marks of a bulkhead that didn't make the cut. It's not that I put it in the wrong place, its just that I moved it after it had already been installed. Oops.

I'm closing in on the last few bulkheads. Once they are all in, I will be able to install the stringers for good, epoxy coat the inside and start closing it up. There isn't really that much in this hull.

One down side so far has been the artform that is tortured ply in a 1 off scenario, there was no way I could predict the exact section shapes and no one has built this hull before. Sometimes you have to let the wood do what it wants to do. All of the bulkheads in the main hull have been painstakingly patterned and hand fit. This just won't do for the amas. I need to speed up construction so I'm working on a more precise way to predict the ply shape so that I can CNC cut the bulkheads and have two identical amas. This will hopefully speed up construction. Stay tuned. Amas are on the horizon.

Tuesday, September 20, 2011

Steady as she goes

Foreword: Awesome work being done on "The Rise" which is the last remaining Wa'apa that sailed to an amazing Everglades Challenge finish after being built by some crazy college students back in 2007. For a history lesson, just dial back this blog a few years. It's great to see her sailing again at . And she makes her return to the racing scene in under 2 weeks at the North Carolina Challenge under Captain Redbeards command.

The new screen I bought is quite amazing. (HP 2311x) It is a far cry from the 10.5inch screen of the netbook that I have been doing all of my design work on thus far. "Holy cow, now the whole boat fits on the screen. Oh thats much easier!"

Below, securing of the 4 partial bulkheads that will support the floor of the main cabin. Nevermind that the "main cabin" is the size of a sleeping bag. Notches are for longitudinal stringers (11mm x 25mm of Western Red Cedar) of which there are 4 plus the keel batten. The floor will also act as a longitudinal stiffener.

Below, a dry fit of the bottom stringers. They must be slid in from the still open transom after all bulkheads are installed. One disadvantage of building from the outside in. Seems to work fine so far.

View forward from the transom. Far bulkhead is the approximate position of the mast. Note limber holes for drainage. The cabin floor will be semi-self draining with holes to the outside to allow a large amount of water to escape automatically. floor hatches will be "water resistant".

Unfortunately for now, the weather is conspiring against me again. The bulkheads that I cut and fit last night no longer fit the hull as the humidity has swollen the sides of the boat just enough to cause a significant gap. Open air shops can be good...and bad. Hopefully I can sun dry the hull soon and get back to work. A coat of epoxy in it's dry state might be next on the list. In the meantime working on cut files for the Amas.

Interesting geometry problem below related to my hull swelling. If you haven't seen it before, the answer might surprise you or maybe not depending on how much of a nerd you are. In any case,

Say I place a 25,0000-mile-long metal band snugly around the earth. (Assume a smooth planet.) Then I cut the band and splice another 50 feet into it, thus loosening it all around. Can I get my finger between the new-length band and the earth? Can I crawl under it?

Friday, September 09, 2011

Irene Aftermath

We have only now just begun to return to normalcy here at the shop. Irene brought with it a 9.3 foot storm surge into Chapel Creek in our section of the Bay River. One of our boat shops flooded 50inches above the floor. Our "high and dry" shop still received 16inches. Irene sucks.

Some of the tools have come back to life after careful cleaning. Our shop bot tool is now operational again. A new computer had to be ordered. I spent a week remodeling the interior of my small cabin with new insulation and wall panels. I had about 15inches of water in my "house". Work has resumed on the 45' power cat and on the trimaran. Another update maybe next week.

The Trimaran main hull was on a pair of short sawhorses in the higher shop and the hull was "splashed" but suffered no damaged. There is a tub-ring type line around the bottom of the hull. At least now no one can say that I didn't put it in the water before the race.