Building is starting. Several questions in here. Answer any you like! :)

To get the fibre orientation right you would then use 90/+45/-45 triax.. of course then you loose the advantage of the continous longitudinal fibres. With multiple layers it might be ok but the schedule needs to be consulted with the designer...

 

Yes that is acceptable. Round holes or half a pipe is practiced. It is the 1/4 span, 1/4 depth that is critical.

 

Quite agree with teddy diver especially with consulting the designer.

However, if you rotate the 0/+45/-45 to 90 degree it will become 90/+45/-45. It is the same fabric but the 0-90 degree orientation has changed, the layup is now on the short side of the fabric.

Cat, you said the plan says to layup all the fabric in 0 degree fashion. All of them? Something seems to be not quite right here. Why concentrate only on the longitudinal strength? I am expecting some of the ply to be 90 degree at midsection, along the keel/daggerboard, or in the crossbeam area.

But again, whatever you designer says, I would not argue.

 

Ok, thanks RX. Good to know a hand laminate (if done well) can be as good as a bagged one.

I do see the 90 degree fabric in the picture. Bilodeau uses the same 90 degree method in his Core Cell book. My plans say warp direction is fore and aft though.

 

Thank you, Teddy. I didn't know it came in the 90/+45/-45 variety. Good to know.

I will repost specifics on the design shortly. I found a disrepancy in the plans I need to ask the designer about.

 

Oops. Just to be clear. You do not put drain holes in the BULKHEAD, only the stiffeners. Bulkheads are supposed to be watertight.

 

Right... I knew what you meant, RX. Thanks.

One thing that's pissing me off today is that my materials list shows various laminates that I have got all ready to order.

These laminates DO NOT AGREE with my plans! WTF??!?

I'm getting pretty upset at the designer today.

In the materials list, he calls out 3 layers of CDB2000 (700gsm) for the hull's outer skin... then in the plans he shows 2 layers of CDB2000 (700gsm) as the hull's outer
skin!

I found 2 other laminate errors like this for the bridgedeck and inner hull laminate.

After the splits both Charly and I had in his CM method, I'm getting quite upset that the plans don't even match the materials list here. That's just damn sloppy, IMO and calls his attention to detail into question.

I have a note into the designer right now basically demanding more accurate information. This guy's carelessness is really bothering me... as this project is a "do or die" type situation for my wife and I.

Will update this thread as soon as I have information on what the real laminate schedule is.

 

Cat,

Now thats what I call concentration. You know know your boat better than the designer and catching up on his mistake.

CDB200 is a code for Knytex triaxial 0, +45, -45 (770 gr/m2) right?

Outerhull thickness is always greater than the innerhull.

 

Yes, CDB200 is an old US manufacturing code for 20oz triaxial in the 0/+45/-45 orientation. It's just about equivalent to 700 gr/m^2. If the code were If CDB2008, it would also have a mat backing on it. A zero on the end means no mat backing.

What is really upsetting to me is that I was about to finalize an order on over $50K of material (my entire net worth) and this guy provided me with incorrect information. Either the materials list or his plans are incorrect. There are 3 such mistakes I've found. Not a good overall sign.

Would any of the professional designers on here have made the same kind of mistakes?

 

Ok, the designer found the correct materials list that agrees with the plans.

Now, it is clear that the outer skin is 2 layers of 20oz (700gsm) triaxial and the inner hull skin is 1 layer of 34oz (1150gsm) triaxial. This makes a lot more sense. Foam is 25mm (1 inch).

The 1" thick foam should be easier to build with since it will need less help from the mold to stay in place.

 

The glass is no problem transverse or longitudinal Triax is easy to come by ,1" core I would use nothing less.

 

Nice!

Now we're getting somewhere. I can picture the entire build in my mind from building the mold to wheeling the finished boat out. That's was my goal.

I even am understanding to take out a little core where reinforcement layers are added (by rudder cassettes, dagger trunks).

Thanks for all your help, guys. It's finally starting to take shape.

Now... I'm thinking I should vacuum bag my laminations on the hull as well as the bulkheads. I'm wetting out triaxial so it seems like a good idea.

I need to figure out which pump to get for this one off project. Any suggestions on a pump, since you guys now know all the details? We talked about my current pump before, but it's not going to be big enough for vacuum bagging my laminates on these hulls. I plan to bag a couple sections a day or something like that.

 

The new laminates are more like I expected, the two outer triaxials are they both still fore and aft? I was expecting them to be at 90 deg to each other to form a quad.

I still say no need to vacuum due to your time limitations.
But if you must your pump is BIG enough, prove it to yourself by making the large bridgedeck panel.
Also if you must go down the vacuum consolidation path then go to infusion. Why settle on still doing the wet messy stuff in small lots when you can do it cleanly in much larger shots.

 

I agree on Andrew:

34 oz triax is not that easy to wet out, it will take a lot of time, especially for the novice, but even for the pro. The 20 oz triax will already give you lots of fun.

I would either:
infuse it, so there is no stress regarding time and laminate quality.
hand laminate it, so there is no stress in time.

I would really recommend you to hire someone for the laminating job. This usually can be done in 2 days or even less per hull (exterior) and basicly the same for the interior. (based on you and the well trained and well performing professional).

As said before, I would hand laminate the exterior, and infuse the interior.