Carbon vs Fibre glass
 

Fellows,

I am just to buy a new rocket ship but the boat can be ordered with carbon hull and that is expensive as he... The sales guy is telling me that I will only gain acceleration (twin Ilmor 725´s) but nothing else except rigidity. I would be most grateful for some feedback in this matter..

/FR

It depends on how the carbon fiber is utilized. Many manufacturers just simply replace a few layers of standard glass with carbon fiber in a wet layup system which does little as far as offering the properties available in a post cured pre preg epoxy laminate. I have seen some pretty high end builders just drop the final layer of glass and replace it with a 2X2 twill weave carbon (which is generally a cosmetic product) and state some kind of "I beam" advantage (BS). Having a boat constructed in carbon fiber can certainly be a big plus but a lot of the advantages can be lost in the process when building a pleasure boat. Find out how they plan to integrate the carbon into the schedule and if it will be post cured. Dont confuse the carbon fiber used in the aerospace/aircraft industry with carbon used in the marine biz. These are laminates that are autoclave cured and carry strength and tensile properties unobtainable in a wet bag system. Carbon is certainly cooler and has a higher "gee-whiz" factor but i sometimes wonder if its really that much better then a well thought out properly bagged S glass layup in the real world here. I have also heard in some cases it produces a very rigid boat that detracts from ride quality a bit.

rocket ship as in Hustler Rocket? If not what boat/manufacturer are you looking at?

Hope Steve Koss jumps in on this one he really is the resident authority on the subject :cool:

Thanks for a professional and informative answer!

Funny you mention the bling factor since the sales rep mentioned exactly that some people like to have carbon in the engine space just to show of.. Since you can buy a high performance car for the price of the carbon option it seems a bit over the top.. Especially if the handling/top speed is not drastically improved.

It is actually a norwegian RIB that most Americans probably have never heard of called Goldfish. Been dominant in the Round Brittain Race. The quality of their products is second to none as well as the design but everything comes at a price... Follow the link below:

www.goldfishboat.com

I have the 29´ now in Carbon with a single Ilmor 725. Tops out at 94.. I love the boat but the 36 P1 Supersport has always been my dream boat and Goldfish has now approved to make one with twin Ilmors. My main issue is how much 550lbs of weight (Is what you save with the full carbon option) makes on the top speed? My guess - not much.

//FR

I suppose another thing to consider is ride quality. Personally I'm not a big fan of light boats just for the sake of speed. Fivehundred fifty might get you a mile or two an hour but handling and ride quality in the pleasure boating environment might suffer as well. A lot of people dont realize that many of those carbon parts are constructed of a 2X2 or 2X4 twill weave non structural fabric with a fiberglass core laminate. There are very few boat building companies doing engineered structural laminations, there are some but not many. If it were me and i was building strictly for pleasure i would probably go with an S glass/vinylester construction and see if they have an appearance option for hatches and things. Good looking boat by the way and it appears to be a quality company. I'm sure they will build a fine boat either way. How do you like the carbon option on your current model? Noticable? I do agree its very cool but they sure are proud of it ($$$$$).

Thanks for your input! My current one is rigid as steel actually.. The hull doesn´t flex at all which I think gives the boat a great feeling in terms of quality but with the flip side that you have no shock absorbation what so ever from the boat itself on full attack. Strangely it also gives me a feeling that the boat will take no prisoners and chop your head of if you relax it the wrong wake.. Might have something to do with a 29 feet V-boat doing 90+ as well. Especially since there are zero freeboards:-)

So basically it all boils down to - taste in terms of ride characteristics, vanity (Bling) and $$$$$ as always..

Thanks from Stockholm!
//FR

yep . . . . ZING! Vs Bling Vs Cha-ching . . . . age old dilemma :D

A 100% carbon fiber lamination in my opinion is a mistake,my ideal laminate is @ 88% S-Glass and the remainder carbon fiber with corecell as the core, You need some energy adsorption in the mix and nothing is better than a linear core for that very purpose,

Plus myself an elongation of 1.7%:eek: in the laminate does not give me a warm fuzzy feeling coupled with a brittle core like Divinycell.

I would ask for a S-Glass laminate and upgrade the core.

Thanks Steve hey did you ever look at Diabs product line to see if they have anything that approaches Corecell or Airex? I still have that issue with the race boat and one of our sponsors is a Diab distributor. They are helping us out on some pricing and we were trying to determine if we could find a Diab product that had similar physicals to the Airex the boat was built with, spoke to Gary Armington and he confirmed it was five or six pound.


http://www.diabgroup.com/europe/products/e_prods_2.html

Yes Airex R63.80 would be @ 5-6 PCF PVC

but talking Divinycell they took PVC and contaminated it with a isonate to cross link the PVC you gain HDT but make it brittle there is nothing I saw that has the same properties what you could do is use a higher grade of "H" like in a hull side H-100 and the bottom a H- 130, You know years back it was all the same color they grew the embryo in a water tank and the higher density was at the bottom and lighter stuff at the top.Airex was done in a autoclave then sliced and normalized..

Cool boat!! The sales literature claims the carbon layup saves nearly 600lbs!