: Good day Paul,

: Woven Roving is usually a thick mat and usually offered in very
: heavy weights like 20 ounce. It is used mostly for thick layups.
: It's loosely woven of thick threads. I use woven roving by
: pulling the strands apart into bundles of loose thread when I
: need to fill a gap, support a fin or skeg, or other times I need
: to strengthen a bond. Other than that it's more for building
: "big boats." It takes tons of resin to fill. Usually
: you lay up woven roving for structure in glass layups and then
: finish with a finer outer layer if you are doing an all-glass
: boat.

: S Glass was developed originally by Corning for military
: applications and is stronger than E glass. It is a biaxial
: weave, tighter and stronger. Also the thread compound itself is
: different and overall you will find a 20% to 30% greater
: strength with the same weight S glass versus E glass. (S being
: stronger)

: You will find E Glass a little more forgiving as far as being able
: to flex into corners and over curvatures, but the difference in
: my opinion doesn't outweigh the advantage of S Glass in
: strength.

: All that said, my recommendation is to go with the Raka 3.25 ounce
: and double-layer it, doing two glassings. The 3.25 ounce, by
: their claim and verified by me weighing surfboards that I build
: with it, once wet out is not much different from just the epoxy
: alone. The glass is thin enough and the weave tight enough that
: it does not absorb much resin. Two layers of this stuff will be
: as strong as 9 ounce cloth, but as light as a layer of 6 ounce.

: A thing to remember is that the weight is the weight of the cloth
: itself. The cloth when fully saturated could weigh more or less
: depending on the tightness of the weave, and the. type of fibers
: in the cloth. I remember buying some cloth locally and the guy
: at the chandlery didn't know the weight of the cloth they sold.
: He said, "What's the big difference, six ounce, nine
: ounce... three ounces- big deal." I explained to him that
: it's not the weight of the cloth, but rather the resin it
: absorbs that makes it so heavy. A 6 ounce cloth will generally
: absorb a lot less than a 9 ounce. The difference will be pounds,
: not ounces, over a whole boat. Also a tighter weave will take
: less resin to wet out than a loose weave. There are always
: exceptions to the rules, but it's a rule of thumb

: I highly recommend Raka.com for your glass. I once ordered 30 yards
: from them of 3.25 ounce. They somehow sent me 20 ounce by
: mistake. I called and told them and they said "just keep
: that, and we will send you another roll of what you
: ordered." I insisted that they at least let me pay
: shipping, as they were giving me free of charge about $400 worth
: of cloth! Customer for life. I will never ever order from anyone
: else due to the service, selection, and knowledge of the
: product. They are in the US but they do ship international. It
: may be better for you to find something local due to shipping
: costs. I think you mentioned you are in the UK.

: Raka also has a very cost-effective resin that gets excellent
: feedback and did very well in One Ocean Kayaks' long-term test.
: I actually have not tried it because I live on an island and the
: only thing we can get on island is West System. I don't want to
: be half-way through a project (and I do a lot of glassing
: projects, so I use a lot of glass) and have to order more and
: wait for delivery. Also it always seems when I start one project
: I always have some West System left over so I end up going with
: West System. I absolutley love the West 207 clear and highly
: recommend it. It's just more expensive. No issues at all with
: quality. I have abused it, exposed it to UV, and basically
: tortured it and it holds up amazingly well.

: Best of luck!

: Malcolm

I agree with Malcolm, I buy exclusively from Raka for both glass and epoxy. Larry at Raka is very helpful and knowledgeable. He'll suggest solutions, find the cheapest way to ship internationally, and is a great guy to deal with. I did a cost comparison on several types of epoxy I could buy both in Canada and the US, and Raka is my most economical choice and I'm very happy with it's properties.

Kirk