America 2.0

The quote is in the middle of page-2.

http://forums.pelicanparts.com/off-topic-discussions/502757-new-boat.html

This is nice work, but it's different.

Wanted to get this forum's opinion on it.

Go to link above for more information and photos:

 

Laminated planks (cedar/end-grain-balsa/cedar)? Aluminum intermediate/tankage section and floors? 23 tonnes of lead hanging off the bottom? What a combination....

This is way cool- I am very curious to see how she turns out.

 

If you go to the Pelican Parts forum for this boat and have any interest in fast cars you owe it to yourself to check out the thread about the legendary Mulholland RSR.

http://forums.pelicanparts.com/off-...3-what-happened-mulholland-king-hill-rsr.html

Chris jumps aboard on page 28 of the discussion and then the fun really starts. He pulls the old car out of storage and does a refurb on the ghost.

As someone who used to go up to Mul back in the days of Chris and his RSR it is a very cool thread for me to read. Every "performance" car I've ever owned has made the pilgrimage to the racecourse for at least a couple of runs.

 

Yikes.......looks all wrong to me....

But what do I know....everybody has to do their own thing...

That's sure not a pretty shape.

 

In your opinion the construction method looks wrong and the shape is ugly?

I do want some diverse opinions, a little more detail would help me understand where you are coming from.

Another Copy & Paste from that thread:
http://forums.pelicanparts.com/off-topic-discussions/502757-new-boat.html

The Schooner America may not be a Bluenose, but what is?

Compare to the Bluenose (my favorite):
http://manthecapstan.wordpress.com/2008/09/04/a-voyage-to-remember/

The Bluenose II

 

Look at the sections and transom shape in your first post and compare to these......




The structure is not what I would do.....dissimilar materials with many many hard spots, fastenings, joints......why? The aluminum will always be expanding and contracting, breaking bonds I would think. Perhaps not if she's always in the same temp water....This gets the tankage down low...but is the effort worth it? Only the owner knows for sure.

 

I'm trying to understand the design in full myself.

I think the mostly aluminum keel tank is the middle part. Above the waterline is wood and a carbon fibre house. Below the aluminum keel tank is the lead/other metal counterbalance.

How these three parts are connected is the art, which I have no experience in. This is one of the reasons I wanted another set of eyes on this project.

RE: transom shape, some sort of butterfly hood gets built around it I assume. What we are looking at just may be the hard plane behind all the add-on's. I do not know this craft any better than you, we share the same information.

This photo of the aluminum bulkhead does indeed show the dissimilar materials adjoining/joining each other, Tad is right about that.

 

I don't get it.
A lot of complication for nothing.
As for the weight saving, until I see the weight estimation sheet I will not beleive it.
It looks like several million dollars will be wasted for not very good result.
Why the keel can be detached for maintenance? Bizarre
I think the owner want complication at any cost, and for sure he will have a very difficult boat to maintain.
As for the shape, the transom seams from a "rater" of the nineteen century, and the side seams to have not the tumblehome, but a hard turn on the bilge.
As far as I see on the picture, a nightmare.
But, He! its my two cents.
Daniel

 

I'm not sure I'd say bizarre considering the need for inspections when ever aluminum and seawater can come in contact.

The US Navy spent a lot of money on their large hovercraft LCAC with the Service Life Extension Program (SLEP) for similar reasons. Even in the sealed buoyancy box they found some corrosion after 20 years.

The next hovercraft and SES are expected to of composite construction to avoid such problems.

America 2.0 is different, which is why I posted it.

Complex? Yes it is, I'm still trying to understand all of it myself.

 

Katch, nice design if its shaping up as I think. Looks like he is building an aluminum keel to be bolted up to a flat bottom hull like most cast/molded keels. The large through bolts are well tied into the keel framing and I am sure it will be bedded into a flexible compound. While working on rebuilding a WWII Higgins patrol boat I have learned they were early adopters of aluminum from experience they had with Vosper. The PT engine room uses several riveted flanges and ring frames tied into the wooden framing of the rest of the boat. Its beautiful in a way and I plan to model it soon as we need to re-produce most of the aluminum parts due to 60 years of electrolysis. These PT boats were expendable so no cathodic protect was deemed necessary nor well understood. Here is a link to a recent expose of our effort. http://www.wwltv.com/video/featured...funds-to-repair-1-of-3-PT-boats-in-world.html

 

Alum/wood

Here is a drawing showing integration of the aluminum plates into the mahogany structure for our old PT boat, seems like your friend is on the right track. These boats never had structural issues and were deployed from the North Sea to the South Pacific so I think the expansion differential is a non issue if allowed for in the attachments.

 

Cool.

Did they spell your name right Dave?

Why would anyone cut the last 15 feet off the PT boat?

I saw something on the History Channel once, they are not made of plywood (as your video proves). The hull is built up of layers of diagonal planks (mahogany outer) with heavy cotton set in pitch in between the layers of wood planks.

QUESTION:
Since you have the PT boat drawings, what is the diameter of the people/turret holes for the twin 50's machine guns each side of the pilot house? I've guessed before at 3-feet, but seen smaller examples on old aircraft.

 

Gun tub

They had a pipe ring to keep the gunner in a 60" radius, just like modern crew served turrets. The dual 50's were limited in down angle by a "depression rail" , which was variable as the gun was slew across the 180 or better sweep. Here is a detail, you can find a lot of PT drawing scans at:

http://louisdl.louislibraries.org/c...TEXT=&DMTHUMB=1&REC=20&DMROTATE=0&x=106&y=344

 

You have a typo - 60" diameter, 30" radius, right?

Thank you very much rambat, I've been looking for that little bit of information for years.

Just checked my hovercraft model, measured 3", or 36" dia. to scale - that is too small.

I think I based the 36" dia on my plastic scale boat Vietnam era PBR31MkII model (bow deck gun), Pac-V hovercraft and on some Humvee (roof top) drawings off the Internet.

Looks like some more info here (model builders):
http://matthewsmodelmarine.wordpress.com/writings/pt-41-building-one-of-the-expendables/