This isn't really a new building technique, I've just tailored standard composite construction techniques to my particular needs. There are other ways to build it though.

I considered carbon chainplates but like Wayne said, too concerned about cracking them. I have however used carbon to attach the forestay bridle rings (triangular rings) to the hull. I've also used carbon as a backing plate inside the hulls at the chainplates and the rudder pintles. The laminate will be de-cored and the hole filled with hard bog where the bolts go. The beam mounts are also carbon for stiffness.

You're right, there's no point building lighter with carbon. However, there is a point in building to a similar weight to glass construction but with much increased stiffness. This is more important from the forward beam to the bridle attachment than anywhere else on the hull. Increasing the stiffness here will directly increase your boats ability to hold forestay tension, which will improve your pointing ability.

This however isn't the only thing that affects rig/forestay tension, the forward beam stiffness will have a huge impact on it as-well.

Weighing up the benefits of potential money sinks is a tricky task. I have decided that carbon mast and beams will be a better investment than carbon hulls. If I had money to burn, carbon everything would be the go.

PS. There's other design alternatives in the hull laminate to increase the global stiffness of the hull platform, in my opinion anyway. You may notice it in the photos. A hint is to think about the hulls with beams attached with the rig trying to twist the hulls.

With the right person on the stick, and if the boat comes in on weight with the good gear on it, then there's nothing stopping the boat winning. Most important aspect is the crew though, equipment is only about 10% of winning (you can get around the course in reasonable time with crap gear), knowing what to do with it is the remainder.

Only one layer of glass on each side of the core. I'd prefer to not tell the laminate just yet until I've taken the boat out in a blow, ie. until I'm convinced it is a rugged boat. Although I may've already revealed it in another post somewhere.

So the general consensous is that a fiberglass boat but with a carbon mast would be a better than a carbon boat with cheaper mast?

Are you sure that 1 layer of fiberglass will be enough? It just seems that it is going to be prone to being hurt, what is normal for factory built boats?

Thank you for all the info Nick, I am sure I will be looking for more as I go on.

I have been working with a CAD program and have the hulls designed, I am sure that I have a long way to go on them but I have the general shape designed?

I read somewhere that people have used masts off old Nacra's to build the beams? What are some other ideas for beams? Could you use an old Hobie mast or are they not stiff enough?

It's a racing machine, don't run into anything too hard and "1 layer" is gonna be enough.

Don't think in terms of layers, you can buy glass cloth between approximately 40-400 gsm (grams per square metre) or more. Your choice will depend on the application.

Just curious what weight did you use? I assume that it varied throughout the boat, but was there anywhere you felt you could go with a lighter cloth while other areas needed something heavier.

I'm not going to reveal the laminate schedule until the boat has seen some heavy weather racing. I wouldn't want to give incorrect information without thorough testing. Let's just say it is heavier than I wanted (or heavier than was needed), but it was readily available.

It wasn't planned to vary the weight throughout the boat, but I did end up using a lighter outside skin on the tops of the decks because I was nervous about going overweight.

In hindsight, I could've used a lighter cloth and thinner core throughout with maybe two extra bulkheads added. As a general rule, the less stiff the hull laminate, the more internal structure is required in the form of bulkheads/frames.

That makes sense about less weight in the material needing more bulkheads/frames.

You said you were nervous about making weight, do you know what they weight in at yet or at least a per hull weight?

It's a bit vague about hull weight because the rules only state total rigged weight. Generally speaking, if your hulls are between about 22-26kg, you'll be in the ball park, but outside this range is still possible if you take weight out elsewhere...

When performing your weight estimate, leave a margin of about 10-20%!

So 44 to 52 pounds per hull, so I should shoot for something closer to 35?

Thank you again for all the help you are giving me. You are the best possible source of info since you are doing exactly what I plan to.

That conversion doesn't look right, 1kg = 2.2lb.

35lb(16kg) is very light in my opinion. I think 48-58lb is closer. Aim for 45lb and you'd be right.

Okay, I just did the math in my head really fast, I just based it on about two kilo per pound.

I actually have been offered a set of plans for a good price. I think I am going to take him up on it after I see some more about it. That will take some of the chance out, but I am not sure about it yet.

Gree2056-
I am in Little Rock, AR and Rob has a 4.9 in Tyler, TX (in fact I am heading down to his house in the morning to sail with him and another prospective F16 owner) so there are some in your general area. If you ever feel like heading over this way let me know or perhaps you know of a regatta near you I might be interested in? My 4.9 is the original one in the US, I was going to build one because at the time they weren't importing them (this was pre-F16) and I even still have my official plans! However by the time I sourced all the "bits" (mast, beams, boards, rudders and stocks, wood, epoxy, sails, etc.) the cost was going to be very close to what I paid for the demo. I ended up getting direct from Aus. If you want an economical, sort of do it yourself F16 I would start with an old Category 2 A cat and reduce it to an F16 ala what one of the Aussies here did quite successfully. Just my .02-

Kirt

Kirt:

Can you guys come down for Wayward Winds Jun 2-3 at Texas City Dike. www.tcdyc.com Link on the right to NOR. I think Bob Klein is coming down. There is a 4.9 around here, but have not seen it ths season.

Doug

I might should post tomorrow when I didn;t just arrive hoome from my 21st birthday party. So tomorrow expect some class A posts from me when I am sober.

gree2056,
Pitty,
The more interesting posts are mostly made by people when they are not sober.

Congratulations.
Happy 21st.
Regards,
Phill

Wow, I do not remember writing that at all! Well, I guess i had a good 21st, I am still alive, granted my head is screaming at me but that is okay.

I promised some class A posts but I can't remember what those were supposed to be.

I am definently doing this just how is the question. I have a guy offer to sell me plans for a custom F16 that uses the foam fiberglass method, also the idea of buying an old A cat and cutting it down to the right length interests me.

So does anyone know of any old A cat hulls around. Also It seems that there would be substantial work involved in cutting hulls down, possibly as much as building a new boat.

Info one wither of those things would be appreciated.

Personally I wouldn't cut down old A-cat hulls. Not enough volume there and when cut down the volume will also not be in the right place. Better to just buy a pair of real F16 hulls and then complete the rest yourself.

Wouter

New photos are up on formula16.org website.

NCIK, it looks like it is coming along well. I can only say that when I get started that it comes along like yours has.

Like I said someone is offering to sell me plans to a foam ffiberglass boat. It gives me more confidence to start with plans that I know have a good chance to be successful.