Maybe if you ever actually make something you can then weight it yourself
--- In
This email address is being protected from spambots. You need JavaScript enabled to view it., russell wilson
wrote:
>
> hi george
>
> my dragon is ply,is covered...but is not painted on the out side or
> varnished on the inside.
> i am not the builder of mine.
> are you sure the carbon's plans call for varnish and paint?
>
> in relation to your material comparison...something does not seem right.
>
> bothe materials have two parts... resin/carbon and resin/wood
>
> fenolic resin has a density of 1.1..this is in your ply?red?
> are you using west system epoxy in your carbon sample?..density 1.3?
>
> your two samples are the same thickness and size right?
>
> carbon has a density of 1.8
> wood varies from .14 to over 1.0
>
> in each sample you can varie the persentage of the two parts that make each
> sample.
> and this will vary the density of each sample.
>
> if you have a carbon sample 0%carbon/100 %resin...this is as light as this
> combo can be(unless we foam it)
>
> if you have a ply sample(aircraft ply) 0% wood/100% resin...this is the
> heaviest this combo can be.
>
> hand lay up carbon/resin usally comes out at 50%/50%..dosent it?density
> 1.5?
> aircfaft ply looks like moor wood than resin to me..my guess is 80% wood 20%
> resin.with the wood density say .4 .5 .6 .7?
>
> if the wood laminate is 4 parts wood and one part resin it would have a
> density somewere between .5/.8
>
> see why im scratching my head ....thinking the diferance in weight between
> the ply and carbon....that you have put up... at orond 20% to 25%weight
> differance does not seem right?
> my thinking is it should be closer to a 50% weight diferance.
> it also dose not corespond with my testing/samples.
>
> kenny is also qoting that 0.4 mm thick carbon is slightly heavier than 0.8
> mm thick ply...for the entire leading edge skin...that is also close to a
> 50% differance in weight.
>
> is your carbon 6 oz cloth?and how many layers are you using?
> what type of ply/wood type?
> is there a chance the wood is wet?
> did you accidentally type 0.8mm carbon when you ment 0.4mm?
>
>
>
> russ.
>
>
>
> On Sat, Jul 9, 2011 at 10:07 AM, george_rf <george_rf1@...> wrote:
>
> > **
> >
> >
> >
> > I have all these materials.
> > Two ply 284 style carbon non vacuum bagged open lay up is 0.8 mm thick and
> > weighs about 85 grams.
> > 0.8 bare plywood is 60 grams sq foot. Bu the time the plywood is varnished
> > on the inside and fabric covered and painted on the outside it will be about
> > the same weight as the carbon just painted.
> > Grain vise the plywood has about the same stiffness as the carbon however
> > it will break much sooner then the carbon will.
> > Across the grain the plywood is obviously much less stiff and far weaker
> > then carbon.
> >
> >
> >
> >
> > Disclaimer ; opinions of others will vary depending on what they're
> > selling
> >
> > This is my website
> > curedcomposites.netfirms.com/index.html
> > Look all you want but don't touch 