Considering building a boat..

99,

If you're dead-set on thin aluminium, I'd go talk to the aircraft guys about flush riveting and general construction techniques, in fact, we have an old russian hydro-foil sitting around here that was built that way.

But on the other hand, if you wanna have a bit of fun, there is a book out there (forget the author) about boatbuilding with explosives. The idea is to use the pressure generated to force a sheet of aluminium into a mold-cavity.

Yoke.

 

Bonding aluminum requires special preparation of the surface. You can't just scuff the surface, wipe with a solvent and apply epoxy. You have to build up an oxide layer on the metal that has sufficient cohesion and adhesion to support the bond. Then you glue to the oxide layer. Otherwise water vapor will penetrate along the bond and weaken the joint. And there's no avoiding the water vapor when the application is a boat!

Building up the oxide layer requires professional chemical treatment. It's beyond the facilities of the backyard builder. But the treatment is not prohibitively expensive. You want to ask for phosphoric acid anodize (PAA) and corrosion-inhibiting adhesive primer (CIAP), per Boeing specification BAC 5555.

There's an excellent discussion of this in Marshall's book, "Composite Basics."

 

How much is shipping???

Im dispairing. I spoke to a girl who shipped a container to jamaica. $15000.
Jeez...
The idea of this boat was that I could take off 3 or 4 months one of these years and sail around australia... having preshiped the boat there.
I also caught an invoice at the office... ~$1500 to ship a container to port of neward. another ~$1500 for loading operations.
Does $10,000 to ship a continer one way to australia sound right?
Then its $40,000 for round trip shipping of a larger design that needs a container for each hull. Damn thats a lot of money...
Otherwise its sailing around the world. In which case maybe I should consider a partial or full deck cabin cat design??

 

Further second thoughts on this project...

Okay, Im over steping myself...
If Im trying a new construction technique, I should build a small boat first and then try and sail it some...
Okay, final design- 30-32' open deck cat...
Im not sure if this imply's a trampoline deck....
Smaller size suggests a single engine... Frankly I kind of liked having an empty rear bar. I was imagining a pair of adjustable platforms, linked so they are parallel and horizontal. 8" wide, that could be swivelled so that it could transition from a swim platform at water's heigh, to a flat rear platform to a step up. this way you could back into a dock or use it as a swim platform....

Any suggestions on power plant?
is there such a thing as an fixed azipod with electric drive in a 5hp size??
maybe twin 10 hp's... I saw 25 hp komatsu outboard cheap-new....

 

Closing thread

Im rethinking this concept as I indicated in my next to last post.
Will start a new thread on it this weekend.
Dont post more here.
Thank you all for your wisdom and advice.
Aeron.