Carbon Over Glass Question, Lamination schedule questions.

[adam_designer]

i will copy any comment of you. its gonna be my MANUAL BOOKS,,hahaha. its hard to get composites materials /books on my region.

[tunnels]

Originally Posted by adam_designer

i saw review of Eric sponbeg on this thread
Carbon/Glass relative strengths

According to his research (but was used sandwich and I will use solid) Does it makes sense if I uses these followong schematic?

outside to inside
csm 300x2 (or csm 600)
db800
db800
carbon uni maybe 90 (??????????)
carbon uni maybe 0 (?????????)
Db800
Db800

Needs your comments again.....na matter what u say. now im waiting while cover my face.

Rather than using layers of uni you would be better to use a woven material of the equivlent weight of the carbon uni's
Me i would be shifting the angle of the second layer of DB so you have 60degrees on the second layer outside and the repeat on the inside

[adam_designer]

carbon orientation:
0 degree is along the boat aft to the fore.

[adam_designer]

Originally Posted by tunnels

Rather than using layers of uni you would be better to use a woven material of the equivlent weight of the carbon uni's
Me i would be shifting the angle of the second layer of DB so you have 60degrees on the second layer outside and the repeat on the inside

Is that i wont get benefits by applying the carbon in the middle???

[tunnels]

Originally Posted by adam_designer

carbon orientation:
0 degree is along the boat aft to the fore.

0 is always along the length 90 across .

You could simply use 600CSM on the outside and 5 layers of uni 400gram and a 450csm to finish off on the inside .
Angle of the uni is critical !!!
What would anyone use ??.

I have made a surf life saving boat more that 18 years ago and is still in use to this very day ,has seeout 6 hypolon tubes over that time . Used just the standard polyester resin for the whole construction and all hand laid glass .

After some other people have posted some answers i will tell you what angles i used that worked a treat !!!.

Think about a hull travelling at high speed through the water and crashing into waves full speed with lots a weight in the boat .

I cant see any advantages to use carbon what so ever , to me its pointless !!
What do you think the advantages will be ??
I am interested why you chose carbon !!!
Remember what i said before about mixing unmatched materials !!!

[Herman]

We do not know what type of boat it is. So any guesswork is just, ehhh, guesswork.

Is the boat using 300 hp, 500 hp, or perhaps 20 hp? Will it sail on the ocean in windforce 12, or on a protected lake with no wind nor waves?

Will it carry load? People? How much? Charter? Will the boat be private owned (careful owners) or is it for the military (bunch of young dudes that have no other thing to do than demolish community property). Will the boat be beached? At what speed? 40 knots?

Why does the owner want carbon? Because he is knowledgable?, or because he "heard something".

Do you want single skin? Or cored construction? What are the other reinforcements? Frames? What specs and what spacing? Inboard? Outboard?

What is the expected lifespan of the boat? 5 years? 10 years? 30 years? Forever? (in that case, please sculpt a RIB from a block of granite)

Certification? Lloyds? CE? ABS? anything else?

All things to know before a laminate can even be guessed. Add on to this the availability of materials, knowledge and circumstances in your yard, prefered building method, and only then one can arrive at a proper laminate schedule. Which actually will cost money.

-----
Carbon and glass:
Think of glass as a rubber band.
Think of carbon as a steel wire.

Imagine a rubber band that can lift 1000 kgs, and a steel wire that can do the same.
When we tie the band to the wire, can we lift a 2000 kg weight?
No, we will lift untill we break the steel wire (the carbon) then lift untill we break the rubber band (glass).

Things I do agree are the use of some CSM on the outside, for gelcoat protection during layup, and as a print blocker. Use peelply to get a good secondary bond with your infused laminate.

This laminate can be either carbon or glass. And the funny thing is that stiffness will be not much different if the laminates have the same thickness. Price will be different though.

As a quick and dirty trick you could sandwich the glass with layers of carbon, to gain some stiffness. But as an engineer you should realise that the carbon will take the full load (almost) so there needs to be a sufficient amount of carbon. The glass will act as a core material in that respect.

Another thing to keep in mind is galvanic corrosion. Any (submerged) contact between carbon and (stainless) steel, and the steel will dissolve rapidly. A layer of glass over the carbon helps in that respect. (keep in mind that drill holes will also need protection). This is a good reason to mix some glass on top of a carbon laminate.

I hope I have given you some information you can sleep on.

[adam_designer]

thanks people. all work done. no carbon stuff except 200 gsm twill weave on console. Thanks again.

[adam_designer]

this thread and all of your explanation has damn good effect to my career and my knowledge.