Quote:
Originally Posted by bschloop
back to the actual build...
I've been looking at different fiberglass cloth, and need a little advice. which makes a stronger more rigid composite, more layers of lighter cloth, or less layers of heavier cloth? this is assuming that the two would have the same final weight.
|
Ideally, I would use let's say 1/2 inch pink foam with one layer of 6 ounce glass on either side of the foam. This is what is meant by the term composite: using two different and weaker materials in combination to make a stronger result.
The foam by itself is very flimsy and the glass by itself is highly flexible; strong in tension but no strength in compression. But put the two together and the result is strong in tension and compression. And the resulting product has a strength/weight ratio much better than any amount of multiple layers of glass by itself.
That combination is used for several full size aircraft with very good results.
In my build, I used thicker foam simply because I needed extra thickness in areas to file/sand the surface back down, since I could not easily predict how thick it would end up being in the design/build process.
----- Check the many pictures I have on this topic -----
In fact, it may be easier just to bite the bullet and start the project with 2 inch foam in areas where your not sure about the exact shape. That leaves you with enough thickness for a lot of experiementation and still have adequate strength when your done.
Jim.