fiberglass foam sandwich mast

If fiberglass for a mast is too flexible on its own- isn't it worth it to use foam sandwich to stiffen it?
or weight\price benefits in this case will be non existent?

 

A mast bends based on the stiffness of the outermost fibers and the size. and the direction of the fibers - they need to be along the direction of the mast (mostly).
Adding foam then glass inside means you are adding stiffness where it is not most used.
So that is extra weight which is not taking the bending in the most efficient weight.

If your mast is so thin that it will dent from outside forces, then foam/ glass will help with that, but you might be better off just putting the extra weight in the outside.

If you have foam, and you need to put a fastener thru it, you need to have taken out the foam and replaced it with something hard locally - wood, glass, etc.

 

Thank you very, VERY much!