I found this video of Carbon Fiber vs Steel. I didn't realize it was that much stronger than Steel !! It seems you would be able to build a super light weight yacht and have the strength also. Can anyone really dispute this? http://digg.com/video/how-much-stronger-carbon-fibre-is-than-steel
Have you ever been on a carbon fiber yacht? I've been on a cold molded sportfish encapsulated in kevlar. It is extremely NOISY. I've heard Carbon Fiber is very noisy as well. Carbon fiber also is very strong but doesn't deal with impacts very well, such as a fast grounding or hitting something so I've been told. Steel tends to be the best common material for impact resistance. That is why it is used for ice breakers and tug boats and commercial ships.
Jarrett bay cold molds and wraps their boats in fiberglass. From what I hear the ride is extremely quiet. I think builders will always use steel because of cost and being familiar with steel compared to carbon fiber. The video is showing impact or strength? I think both
Cold molded and fiberglass is very strong and quiet. Cold molded and kevlar or carbon fiber is not quiet and it sounds like the whole boat is disintigrating.
Kevlar would be the best choice for impact resistance. It has a higher sheer strength and it's more resistant to abrasion. Carbon fiber has great tension and compression properties. It's stiffer and lighter than Kevlar, but more brittle. Ultimately, it's a matter of structural engineering, laminate and insulation. I sea trialed the all-carbon Delta 54 while in Monaco and it was quieter than many other boats I've been on in that size range. In contrast I've been on a custom built, all-carbon raceboat that resonated every slap of water against the hull.
I agree. Personally, I think the greatest amount of weight savings can be had on the interior, and non structural components of a yacht. The interior woodwork for example. I have seen many aspects of the interior where weight could be shaved without any perception of luxury loss. I can tell you this much Kevlar over Okouma plywood in a cold molded SF is extremely loud at 35 knots. Monterey built 13 boats that way starting with the Glass Machine in 1988 and ending with the Gina Lisa in 1991. The other funny thing is I ran a 77' Aluminum crew boat out of aluminum and up until 8-10' seas it was completely quiet and smooth, then all of a sudden a wave would hit the bow 1/4 and you'd get a dong sound.
Capt J, could you elaborate more on what type of noise you're hearing on those cold molded hulls? Engine noise, wave slap, machinery vibrations, etc.? I'm asking in all seriousness because all of our hulls are also cold molded with an Aramid outer skin and I haven't observed any noticeable difference in sound transmission through the hull compared to "regular" E or S-glass sheathed hulls. If there's an issue I'm not aware of I would very much like to learn more. If you prefer to keep it private a PM would be fine as well.
CF hull triples the build cost. Recently I ran a boat for a survey that had a 14 year old CF mast. The mast had electrolysis damage from the aluminum boom. Never would have guessed that could occur. Carbon would be my material of choice if you could fund the build.
I hope you will post these details here as I have been following the cold mold threads elsewhere and new info is always appreciated.
While in years past the "triple" cost may have been true, in the 21st century the development of new techniques, as well as technology, have changed that number. Look at how carbon fiber is being used in aerospace, and is finding use in commercial vessels as well. In the overall cost of a yacht, most particularly one where the weight and strength benefits of carbon fiber come into play, the actual percentage of the total build cost to generate the carbon fiber structure is a small part of the grand sum.
Many composite builders use carbon fiber in their critical area build ups. In the past they would use a much heavier build up of glass in the prop pockets and where appendages were to be attached like struts rudders and stabilizer box's and keel box's . Now in lieu of the beefed up glass layup they're just laying in a few runs of C.F with the best of both components , strength Vs weight. Christensen likes to advertise it's famous " Two point pick" and when you look at all the unsupported space between the dollies it's a good testament to the strength of CF
As I look around my office at all the high strength structural composite sample parts and test pieces, it really puts it into perspective the ever changing technologies for manufacturing. When you compare the ferrous metals industry really coming about with steel production in the 1850’s, composites is essentially still in its infancy and very much unknown in its uses and capabilities over steel to the general public. As CaptPKilbride touched on the cost factor of Carbon and all composites essentially have reduced from a manufacturing and material cost standpoint, and as much as aerospace has driven those cost down with manufacturing techniques, the auto industry is really pushing it to new levels of layup/molding/resin technology which will spread into the marine industry as both are mindful of manufacturing cost compared to aerospace. For me if I wanted performance, ride, and strength for a SF hull I would build with a hybrid of S-glass/Aramid for the hull and carbon fiber for the toilet seats and interior.
I believe that would be Jon Sadowsky who worked with Jim Smith and recently passed away that built the Revenge.
Yes, Revenge has been building later boats out of Carbon Fiber and planned on building a 58' SF out of it until Jon Sandowski's demise. I believe they did build some 35' ish center consoles out of carbon fiber. He did build 3-57' SF in the late 80's early 90's out of I believe Kevlar. All 3 remained owned by the origional owners up until a few years ago. Cookie Too was one of those boats and the performance numbers were VERY impressive even by today's standards. Cookie repowered with 1100 common rail MAN's because the old 1350's were too fast and it still cruised around 33 knots with the 1100's. All 3 I believe also had massively tall Tuna Towers. Revenge (and Jon) was another pioneer much along the same lines as Jim Smith, although I don't think he became as successful, but still built some cutting edge and fast boats.