Thanks for the detailed response. I was pointed down the vinyl ester road by a local supplier who has experience with both poly and epoxy resins but, not much over wood. I have found the following:

http://www.resinnavigator.org/html/benefits.htm mentions "epoxy based vinyl esters" and has a some technical detail as well as references to case studies on kayaks and bass boats. The article does not mention its bonding properties to wood.

US Composites has some poly & vinyl ester resin products at http://www.shopmaninc.com/polyesters.html and a pretty good selection of fiberglass, kevlar, carbon, and hybrid fabric supplies.

I agree with Jay Babina on not scrimping on the resin. Prices seem to range from $20 - $40 per gal although price is not the reason I started looking. My local source implied that there were benefits of vinyl ester over epoxy, specifically with respect to UV resistance.

Thanks again. As a dedicated lurker, I really appreciate the open discussion on this board. Hope to have my first boat, a Coho, completed in a few weeks (using epoxy by the way). I do have Guillemot forms queued up.

Greg

: It has been discussed a few times. It is not as widely distributed so
: probably fewer pople have played with it. Of the three "common"
: resins used with fiberglass, it is probably the least common. It costs
: about as much as epoxy, so there is no price advantage, unlike polyester,
: which can be found for considerably less.

: Handling wise it is similar to polyester. Like polyester resin it cures by
: adding small quantities of an accelerant or catalyst. At room temperature
: you would use under an ounce of catalyst for a gallon of resin, so careful
: measuring is important.

: I can't find any references to this material soakin into the wood pores and
: sealing the wood as epoxy resins do, so I am inclinded to think that this
: has the same characteristics as polyester. That is, it is probably
: slightly permeable to water vapor, so it does not prevent rot.

: I believe the same catalyst can be used for either polyester or vinylester
: resins. You have some control over the potlife and cure times of these
: resins by adjusting the amount of the catalyst added. On hot days you can
: slow down the process by using less, and on cold days you can speed up the
: reaction by using more -- all within certain limits, of course. The resins
: are a bit "thicker" than epoxy so they create fewer runs and
: take a bit longer to wet out the cloth.

: Fibreglast (www.fibreglast.com) has this for $52.95 a gallon, and it has a
: short shelf life. Polyester resin from these people is $37 to $38 a gallon
: by comparison. Here is their description of the material: General Purpose
: Vinyl Ester Resin
: Tough and Corrosion Resistant
: This vinyl ester resin is formulated for maximum corrosion resistance to most
: fuels, vapors, and both acidic and basic chemicals. It is also heat
: resistant and blended for toughness. These qualities make it perfect for
: repairing tank linings, blistering boat hulls, as well as fabricating
: tough all-around parts. Catalyze with 1.25% MEKP, Shelf Life Limited to 3
: months.

: - - - -- - - - -- -

: Hope this helps

: PGJ