mscres wrote:
Please help.
Anyone can tell me the expense per square footage of fiberglass/epoxy?
I need it for every thickness of fiber glass? TIA

This will depend on several factors:
First you need to figure out how thick the fiberglass needs to be based on
design and usage. Heavier glass requires more epoxy.
Then you need to figure out the type of resin you want to use. A high grade
epoxy resin can cost over twice what a low grade one will but you don't want
to use cheap materials when doing this sort of thing.
Next you need to know how many layers of build up epoxy you are going to use.
If it is not going to be visible or below the waterline then you might get
away with just wetting out the glass but if you are planning on painting or
varnishing it, or it is below the water line, then you need a few layers of
build up resin to fill the weave in fiberglass. A slow drying resin is
easier to work with but is also thinner and requires more layers.
You also need to allow for spills and screw-ups so add a little extra per
square foot for that.
Then you need to figure out how you are going to do it. If you are going to
do fiberglass over a mold, it requires more glass and a core material. If
you are going to do a wood strip or plywood then you use less glass but need
to buy wood.
There are also different methods of laying the glass. Hand laying is the
least efficient but easiest to do. Vaccuum bagging is just hand laying with
a vacuuming system to remove excess resin, cost increase is due to bagging
tools and materials but there is an increased strength to weight ratio.
Vaccuum infusion costs the most in tools and is the hardest to set up but has
the least amount of waste, saving money, and the highest ratio of strength to
weight. Infusion is a bit more complicated and as far as I know can only be
done on fiberglass construction on a mold of some sort. If anybody out there
knows a way to use this method in a strip composite construction I would love
to hear it.

More detail might help like what kind of construction you are planning and
what it will be used for. If you are building something designed for you
then what are the design recomendations. If you are designing it then a size
of project and probably usage will be helpful. Of course you may not be
building a boat at all but instead just making some small parts for something
else, in which case you could possibly get away with cheaper materials.

A good site with a lot of basic info and some formulas to help with this is
http://www.fibreglast.com/

They carry a lot of stuff as well but I don't think they are the best prices
and I can't vouch for thier material quality.

What are you building and what are you using it for will be the most
important things to think about before figuring materials, then you can
figure out cost of materials.

P.S. A lot of people here will tell you that if you dont know everything by
now then don't build anything. Don't listen, if you are asking questions and
trying to learn then you can build. Just remember that it will take a long
time and a lot of patience. Also it is always more expensive than you plan
for, especially if you are a beginner. If you really want to build something
then go for it. Don't let anybody tell you otherwise if you are really
determined but do your homework and do a lot of practice before you get into
the actual build.

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