calculating laminate thickness

Just for the hack of it:

Lloyd's SSC Rules - nominal thickness of an individual ply:


m*{(Pa/f) - (Pa-Pr)}
------------------- = thickness of individual ply
1000 * Pa * Pr

m = mass of reinforcement in individual ply.
Pa = spec. gravity of reinforcement in individual ply.
f = fibre content by weight, of individual ply.
Pr = spec. gravity of resin in individual ply.

At the end you just add up.

Because this is a class calculation I presume it's pretty conservative, but that's better then 30% + or -.

 

Thanks Dutch Peter. I have enough now to learn how to do it from first principles. That way I understand instead of blindly following along.

 

I'm sorry - I am not sure that I understand your questions!

How could you tell?
If you mean "How could you tell that +/- 30% sounds interesting"? Well - a margin of error of that magnitude on a formula referred to by one of the really BIG players in marine composites (SP Systems) sounds interesting to me!

Have you read that in some book or in some URL?
Read what?

Please explain!

 

Huuh !

 

Slowmo,

You're clearly lost for word, otherwise you would have given an answer that makes sence, I'm sure.
Ofcourse you can come up with a foam that absorbs more resin than the fibres, but Sorendfk means foams normally used in boatbuilding, and not in aviation or aerospace application.
I'm sure that's the confusion.

 

I only asked because I would like to know, but if you don't want to share your knowledge and/or experience like most of us here, then that's entirely up to you...

BTW, one of your earlier postings seems to have disappeared! It was the one with the question "How could you tell?" Did you delete it? If so, then why? I would still like an answer...

 

Slowmo (or Morgan or whatever your name/alias is):

A long time ago, I asked you a question. Why don't you answer?
And why would I would I want you to answer? Just because I'd like to see you admit (here or on marinan.com) that you are dead wrong!
Come on - show some of the netiquette you have asked of others!