Vinyl Ester Resin vs. Polyester Resin

[tpenfield]

Since I am going to be buying some fiberglass and resin materials for my bulkhead and Stringer replacement project, http://forums.iboats.com/showthread.php?t=534913 I am wondering if there will be an advantage to use vinyl ester resin to adhere to the hull and existing fiberglass surfaces.

I believe that the moisture resistance is better with vinyl ester versus polyester, but I am not sure if there is an advantage for adhesion. Also, not sure about strength differences between the 2.

T.I.A. for your advice.

 

[Friscoboater]

Re: Vinyl Ester Resin vs. Polyester Resin

Vinyl from what I understand is the "in between" of poly and epoxy. I think your boat was made with Poly, so that is what I would stick with.

 

[ondarvr]

Re: Vinyl Ester Resin vs. Polyester Resin

VE is better, but the answer to the question about it actually making a difference you may notice in doing the repair is a little more difficult.

Water resistance isn't that big of a deal on stringers and while VE will bond better, you will rarely have an issue with the bond unless you do a sloppy job.

Many thousands of new boats have been, and are, being made with low cost polyester resin for the entire boat (some use a better resin as skin coat on the hull) and for the most part they hold up fine.

If you will sleep better at night by using VE, or the cost doesn't come into play, then go for it.

 

[tpenfield]

Re: Vinyl Ester Resin vs. Polyester Resin

Thanks for the replies . . .

Yes, the majority of the layup is polyester (from what I can gather from Formula's product information). The first layer (or two) of layup in the molding process is VE for moisture barrier, but then sebsequent layers are polyester.

In terms of my Stringer & Bulkhead project, I was thinking that better adhesion to the existing polyester (hull) may be a good thing - even though I would prep the poly surefaces - does fresh poly adhere well to cured poly? . . . or would VE be better to adhere to the existing poly?

If VE would be better, then I would use it in areas where adhesion to the hull was important ('tabbing in' areas, etc.) and then use poly for the rest. OR . . . if I start with VE, should I use it throughout the repair work ???

Cost is not a huge issue as it appears to be only about a 50% uplift on the cost, and I would not use too many gallons.

 

[Cadwelder]

Re: Vinyl Ester Resin vs. Polyester Resin

Thanks for the replies . . .

Yes, the majority of the layup is polyester (from what I can gather from Formula's product information). The first layer (or two) of layup in the molding process is VE for moisture barrier, but then sebsequent layers are polyester.

In terms of my Stringer & Bulkhead project, I was thinking that better adhesion to the existing polyester (hull) may be a good thing - even though I would prep the poly surefaces - does fresh poly adhere well to cured poly? . . . or would VE be better to adhere to the existing poly?

If VE would be better, then I would use it in areas where adhesion to the hull was important ('tabbing in' areas, etc.) and then use poly for the rest. OR . . . if I start with VE, should I use it throughout the repair work ???

Cost is not a huge issue as it appears to be only about a 50% uplift on the cost, and I would not use too many gallons.

ondarvr answered all of these in post #3. VE does cost more and is better is most every way to polyester, but polyester is fine for all your repairs. As ondarvr said, as long as your prepped good (as with most any repair) you'll be fine.

 

[ondarvr]

Re: Vinyl Ester Resin vs. Polyester Resin

Does it bond better...yes...will it make a difference....not likely. The bond only needs to hold up the stresses it may see during its life. Polyester to polyester bonds are used in almost every boat that has been built over the last 50 years and they don't commonly fail, so is the extra strength needed....

Or you can up grade to epoxy, it bonds even better than VE and is much stronger.

If engineered correctly a polyester, VE or epoxy hull will all be the same strength, the only real difference will be the weight. A boat built entirely from epoxy will be lighter for the same strength, which can be a big help in a high performance craft. But the amount of weight saved by doing a repair with it will be about the same as a six pack of your favorite drink.

 

[Friscoboater]

Re: Vinyl Ester Resin vs. Polyester Resin

Poly will outlast your interest in the boat.

 

[fatboy308]

Re: Vinyl Ester Resin vs. Polyester Resin

hi i bought a 1984 26' carver monterey i noticed under the deck portside at i guess the bulkhead the fiberglass wall ( very thin 1/8" with no plywood on inside) it is separated from the bottom hull from the out side rib to the side & up 1/2 way is this a load bearing structure or is this just to keep fumes out of the cabin??? it is fiberglassed in only on the stern side & not very much mabe 1" i need to know if i need a total rebuild for stucture or i can just smoo it to seal it up????? anyone please help mark

 

[ezmobee]

Re: Vinyl Ester Resin vs. Polyester Resin

anyone please help mark

Please start your own thread.

 

[fatboy308]

Re: Vinyl Ester Resin vs. Polyester Resin

Please start your own thread.

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