how important is Epoxy resin in the construction to you?

[Redbull addict]

if you were buying a new boat, how important would it be for you that the hull is built with epoxy resin versus vinylester or polyester? Would it even make your list? I know there are more important specifications in selecting a boat, I'm just curious about this particular element.

[delmarrey]

Other then the cost, is would be acceptable to me!

[GordMay]

I’d rate both vinylester and epoxy resins above polyester. The more difficult choice, for me, would be which specific epoxy (or specific VE).

[44'cruisingcat]

Do any builders use polyester resin these days? That would suggest a pretty high degree of cost cutting - while epoxy is quite expensive, vinylester resins are reasonably priced, and given the relatively small difference in price between the two, (compared to the overall cost of the boat) and the greater resistance to osmosis of vinyl, I would probably tend to avoid a new boat built using polyester. If they are that intent on cost cutting, you would have to wonder where else they have tried to save money.....

[Pura Vida]

For normal recreational boating all of them are workable. A walk through most marina's will find a number of 30 and 40 year old polyester boats. During my early college years I was employed working on polyester tanks for the food industry and most of those tanks are still in service. But after building two poly boats and one epoxy one, I prefer to work with epoxy. Personally the price of the finished boat would be the important factor for choosing one over the other.

[Whimsical]

My 40 footer will use about $10,000 AUD of epoxy how much would vinylester save? 5,000 maybe? Out of 250,000 total materials not worth thinking about.
Might make sense if it was a solid laminate construction.
Mike

[cat man do]

I would not have a new Polyester boat, and I would not have a timber cored boat unless it was epoxy.

I also won't have a boat with CSM, Woven roving's or chopper gun snot.

Foam and Vinyl would be fine though, stitched fabric's only
Timber and epoxy and the same.
Foam and epoxy and the same.

Fussy bugger is me.

Dave

[Efraim]

"Epoxy resin is known in the marine industry for its incredible toughness and bonding strength. Quality epoxy resins stick to other materials with 2,000-p.s.i. vs. only 500-p.s.i. for vinylester resins and even less for polyesters. In areas that must be able to flex and strain WITH the fibers without micro-fracturing, epoxy resins offer much greater capability. Cured epoxy tends to be very resistant to moisture absorption. Epoxy resin will bond dissimilar or already-cured materials which makes repair work that is very reliable and strong. Epoxy actually bonds to all sorts of fibers very well and also offers excellent results in repair-ability when it is used to bond two different materials together. Initally, epoxy resin is much more difficult to work with and requires additional skill by the technicians who handle it."


"Vinylester resins are stronger than polyester resins and cheaper than epoxy resins. Vinylester resins utilize a polyester resin type of cross-linking molecules in the bonding process. Vinylester is a hybrid form of polyester resin which has been toughened with epoxy molecules within the main moleculer structure. Vinylester resins offer better resistance to moisture absorption than polyester resins but it's downside is in the use of liquid styrene to thin it out (not good to breath that stuff) and its sensitivity to atmospheric moisture and temperature. Sometimes it won't cure if the atmospheric conditions are not right. It also has difficulty in bonding dissimilar and already-cured materials. It is not unusual for repair patches on vinylester resin canoes to delaminate or peel off. As vinylester resin ages, it becomes a different resin (due to it's continual curing as it ages) so new vinylester resin sometimes resists bonding to your older applications, or will bond and then later peel off at a bad time. It is also known that vinylester resins bond very well to fiberglass, but offer a poor bond to kevlar and carbon fibers due to the nature of those two more exotic fibers. Due to the touchy nature of vinylester resin, careful surface preparation is necessary if reasonable adhesion is desired for any repair work."

Short answer, depends what you use it for.

[Boracay]

In my limited experience epoxy would not be easy to mould. Too sticky and too hard to mix large batches.

So the conventional way of building a production boat using a negative mould may not be practicable.

Vinylester has been developed for fibreglass moulding so should be suitable.

A custom boat could be built with epoxy on a positive mould.

[Alan Wheeler]

Both moldng techniques are used. I have seen an entire race boat layed up in a Female mold with Epoxy as the resin. The major advantages of using Epoxy is that you can get very thin lightweight shells with equal strength as you woudl a thicker heaveir shell from Ester resins and choped strand methods.

[roverhi]

Better not tell Tartan that you can't lay up an epoxy hull on a female mold. AFAIK, all the newish Tartans are all made with epoxy resin.

Aloha
Peter O.

[Redbull addict]

Originally Posted by roverhi

Better not tell Tartan that you can't lay up an epoxy hull on a female mold. AFAIK, all the newish Tartans are all made with epoxy resin.

Aloha
Peter O.

that's my undestanding also. I have Tartans brochure for the 4300 and it makes a big deal over the hull strength and the fact that they use epoxy. C&C seems to use epoxy on some of their hulls also.

When some manufacturers say their hulls are a composite, does that mean it could be any combination of resins, core, etc, right?

[delmarrey]

Originally Posted by Redbull addict

When some manufacturers say their hulls are a composite, does that mean it could be any combination of resins, core, etc, right?

Basicly, this usually means epoxy and plywood or wood strips laminated cris-crossed. But it can mean most any combination.

I once had a guy try to convince me his ferro hull (for sale) was composite. That one cost me a day off work and a $500 plane ticket.

[Efraim]

Originally Posted by Redbull addict

that's my undestanding also. I have Tartans brochure for the 4300 and it makes a big deal over the hull strength and the fact that they use epoxy. C&C seems to use epoxy on some of their hulls also.

No matter what Tartan says, the outer hull on their boats is still gelcoat, epoxy is used somewhere is the lamination process. Using epoxy resin rather than vinylester resin puts them at a price disadvantage over other builders, so they have to be carefull how much and where they use it. Note that in their marketing blurb they don't mention that they don't use vinylester resins, just that they use epoxy resins, in some applications.

Originally Posted by Redbull addict

When some manufacturers say their hulls are a composite, does that mean it could be any combination of resins, core, etc, right?

Basically that means anything they want it to mean, it's useless marketing nonsense.

[Alan Wheeler]

I once had a guy try to convince me his ferro hull (for sale) was composite. That one cost me a day off work and a $500 plane ticket.

Yeeaah well I suppose yah could..........nah who am I kidding, he must have been a right dick.