Resins and their fans

[gonzo]

I find that epoxy is hailed as the solution for everything on boats. It's advocates claim that no other resin can be used. I have done repairs with polyester and vynilester and build new boats too with no problem. Boats that were originally built with polyester and mat over plywood, should have no problem being repaired as originally built. I also find polyester more forgiving of contaminated substrates. Probably the solvents have something to do with it.

[waikikin]

I love gelcoated polyester/vinylester boats, epoxy has its place but a fresh shiny contact molded boat is what I like, all the best from Jeff.

[Herman]

I love both. But if my neighbour was to build a boat, I would definately recommend epoxy, even it it was just for the smell... (I live in a condensed area)

I like epoxy better in places with lots of dynamic loading.

In boats, build quality is far more important then resin used. I see them all. Perfectly built polyester boats, perfectly built epoxy boats, which both have no problen surviving very heavy winds. I also see very poorly built polyester boats, that hardly survive hoisting to get it into the water, and ditto for epoxy. (although less, probably because when people use epoxy, they do tend to be more generous in labour as well, and epoxy people tend to be more "technically aware".) All largely generalised, I admit, but this is how I feel it.

I also must say that I fear this will be another "epoxy vs polyester" bashing thread, if not tightly moderated.

[gonzo]

Vynilester seems to be the forgotten resin

[Steve W]

In general ammatures tend to use epoxy for everything because they lack the experience with polyester or vinylester and epoxy is what has been heavily marketed to them in all the retail magazines,pros will generally use what is appropriate for the task at hand. I agree with Gonzo,vinylester is often overlooked,if polyester or vinylester were to be marketed at all outside of trade mags so people could actually learn about the stuff more ammatures would use them.
Steve.

[Typhoon]

I like all resins, if used correctly and appropriately.
I've owned a 35 year old deep V runabout that had seen a lot of big water and it was still perfect, and owned an old state champion Diamond that was sheathed with polyester some time in the 80's and was fine 25 years on.
I currently own a 35 year old GRP production hull that's perfect too.
The deep V runabout is interesting, I have all teh documentation from when it was being built, including all the owner's notes etc. I have a few letters from the owner and Ciba Geigy, talking about their "new" epoxy glues and how to use them, and if they'd be suitable for boat building!

Regards, Andrew.

[jonr]

After having a boat with blisters, I'd prefer vinyl-ester or epoxy.

[ChadRider]

Recently I've been intrigued with UV cured epoxy for application of glass on plywood. Doesn't it seem lovely the idea of wetting out cloth with a resin that won't kick at an inopportune time and then just roll the whole thing out into the sun cure it to green, roll it back in again, fill coat it, roll it out and cure the whole think hard? all in an afternoon?

Surfboarders are playing with this a lot and I think it has some promise. I'm gonna test the mechanical properties of some Zerovoc UV cure epoxy to see if it is good for this purpose.

Chad

[Splint]

Originally Posted by jonr

After having a boat with blisters, I'd prefer vinyl-ester or epoxy.

Is polyester more prone to blisters? I was allways under the impession that would be more of a gel coat issue.

[jonr]

That is my understanding.

http://www.zahnisers.com/repair/blister/blister1.htm

[gonzo]

Polyester is a family of chemicals. Some are more prone to osmotic blistering than others

[pistnbroke]

I was gong to post a thread but I think I found one on the subject..I have always used polyester resin and had no problem .I was looking at plans from www.epoxy-resins.co.uk ..a plans and resin kit ...I asked if I could use polyester resin instead of epoxy ...stitch and glue and the guy Rob Hewitt went balistic with NO NO No ...wont stick to the wood he says ..??? I could see a problem with very hard "OILY" hardwood but not marine ply .....
Well I never had any problems so can anyone cast information on what he sees as a problem ?

[souljour2000]

Those stitch/glue folks seem to use alot of cheaper hardwood veneered types of thin 1/4" plys like luan and so forth and that other one that is more popular and more expensive....can't remember the name...but they are hardwoods nonetheless and especially on the outer layers...where however thin..they may be a bit oily...and the home-built and stitch/glue crowd that uses that wood may largely use epoxy for that reason...

[pistnbroke]

I have always regarded the ply that I use as a softwood ..I usually use the cheapest ...perhaps that is why I have had no problems with polyester resin .

[gonzo]

Polyester, in my experience, will peel off layers of wood if you rip it.