DMOORE

You beat me too it. I just caught the thread, and it was the first thing i thought of. If I remember, his boat is actually quite lite.


Darrell.

Chris Sunkin

But the one thing that hasn't changed is that aluminum still has about the same strength to weight ratio as it did then. And it still weighs exactly the same. You're going to have a challenge matching the weights of something like a Skater

Tha last challenge with aluminum is repairability. That can be a major issue.

nocigarette

I dont have the knowledge or the want to build a state of the art 160mph aluminum cat....I thought it would be a fun project for my uncle and i to work on over the winter....I Just threw it out there to see if someone could help with a set of drawings....

Thanks for your input guys, keep the comments coming...

How is the cig coming chris....

stevesxm

you keep making referance to a " pulse" welder as if it is some high tech nasa spec thing. all you need to weld any kind of al up to 1/2 inch thick is an AC tig welder. a brand new syncrowave 350 with all the bells and whistles is about 3500 bucks these days and will weld absolutely ANYTHING that you can get a filler metal for. i just had one shipped down here just to work on routine stuff ... you can stick weld i beams or tig weld .o20 al with it. working with al is easy. all you have to do is know how and have a reason to do it and there is so much used equipment around that cost can't be an issue. i saw 2 year old syncrowaves for a 1000 bucks...

vtec

I was refering to MIG production type welding, which is faster than TIG and traditional requires less skill.

The 350 was the machine "I heard" was good. I've only done some MIG, and don't want to learn TIG or gas or anything. I don't have a $3500 welding machine at the house nor the amp line rating either.

To my knowledge (I'm no welding engineer) TIG is relatively slow. And to weld a hull with TIG you could go work at McDonalds for the same amount of hours it would take you to weld the damn thing-and buy a skater

stevesxm

true enough. but the quality of a mig weld is generally contaminated and in all ways inferior to that of a tig... and you wouldn't be welding the hull together anyway if youre smart.

never the less if that's the way you want to go then that's your choice to make.

Chris Sunkin

Stagnated a bit. Dave is moving it along but he got bust with throttling the Clevland Construction Talon in OPA so his time has been limited. The project expanded and my time contracted so when it became apparent it wouldn't see wtaer this year, we decided to take our time. Plus as always, the project has expanded. I keep coming up with "I should do that's", if you know what I mean.

Back when I was a kid, the guy that owned Alliance Manufacturing (Genie Garage Door Opener) set off to build aluminum offshore boats. They were called Maritime. I owned one of their 20's once. Built like a battleship and the entire outside was engine turned. I remember seeing the big one's atthe plant when I was a kid in the 60's. Here's one- http://www.offshoreonly.com/forums/s...d.php?t=171539

Naughty Kitty

As a Mech Eng I have always thought a small 26-28 foot cat would be a fun project to design and build as well. I have never concidered the use of aluminum, however as a machine tool designer the majority of our work is in aluminum. Waterjet bulkheads coupled with multiple roll formed stringers could be the basis of an extremely accurate and efficient substructure.

Although I have a 31' cat, I would be interested in getting involved in a single engine project. I have over 20 years in front of CAD applications and am currently using SolidWorks for modeling with Cosmos for FEA. If this projects develops some legs, count me in for support. -Jeff

PatriYacht

HyLite boats in Ontario Canada is building beautiful aluminum v hull boats. http://www.hy-litepowerboats.com/ They have an inner and an outer skin with the gap between filled with expanding foam.

BradH

Unless you can reduce the weight enough to get the speeds up for the hull to start developing lift, I'd say stick with a v-bottom.

Find the weight of some similar frp hulls (preferably unrigged) and see if you can come close to that with a basic aluminum structure.