vinylester resin

[Jerry Cureton]

My boat is being bead blasted tomorrow to remove old bottom paint. I will then sand, and fill and coat with vinylester resin. Sand and fair and then paint. Any suggestions for sanding and applyhing the resin? All help is welcome. This is my first time using this resin. Thanks



jcureton@home.com

[John R.]

My boat is being bead blasted tomorrow to remove old bottom paint. I will then sand, and fill and coat with vinylester resin. Sand and fair and then paint. Any suggestions for sanding and applyhing the resin? All help is welcome. This is my first time using this resin. Thanks

I don't understand why you are coating with the vinylester resin. I think epoxies will be a far better barrier coat. Vinylester is primarily used during layup of a laminate. You don't mention what you are filling with and I assume you are filling blister cavaties. If no laminate is being removed then I would simply apply a epoxy barrier coat around 22 mils thick. I would use either West epoxy with 422 barrier coat additive or Interlux Interprotect. The West method being more labor intensive and I believe slightly more expensive. Whatever you elect to do as a barrier protection coat it will be no better than the condition of the hull before you apply it. By condition I'm speaking of as clean and dry as you can possibly make it.

I would sand the epoxy with a 80 - 100 grit to get a good tooth for the bottom paint. To apply the resins use a Redtree foam roller (phenolic cores) and they won't disintegrate on you. There is also a foam roller at Home Depot that will handle urethanes and resins but seems a little more porous. I prefer the Redtree.

[Kurt]

Vinylester is the most water proof coating you can put on a hull...superior even to epoxy for its MEE (Moisture Exclusion Effectiveness)BUT it's trickier to use. The product has a short shelf life so it must be fresh...buy it from a reputable supplier. Mix small batches at a time and use a foam roller to apply. It hardens a lot quicker than epoxy which can be a double edged sword. Keeping track of the number of coats and where you stop/start each successive coat on the hull. Keep recoating until the desired thickness is achieved. I used a grease penci on the top sides to keep track of my progress and number of successive coats. Vinylester doesn't sand as well as epoxy either. But it does prevent blisters better than any other product.
I believe the previous posting was talking about polyester resin which is widely used to layup fiberglass. Polyester resisn has worse MEE than either epoxy or vinylester and should never be used as a barrier coat.



kjlgpw@AOL.com

[Fred]

My boat is being bead blasted tomorrow to remove old bottom paint. I will then sand, and fill and coat with vinylester resin. Sand and fair and then paint. Any suggestions for sanding and applyhing the resin? All help is welcome. This is my first time using this resin. Thanks

Be sure to mix it very well. Keep in mind that it will kick off quicker when it is hot or in the sun. Vinylesters sand easier after they have had a few days to harden up. I would wait a week or so.



fred@hotsheet.com

[John R.]

Kurt,

If you know of a source where I can read about the tested effectivness of moisture exclusion and penetration resistance between the the vinylester and the epoxy resins then I would like to read it. If indeed there is a much better performance of the vinylester that I'm not aware of then I want to know about it. In my readings I have come across nothing that makes that claim. Some hull manufacturers are using vinylester for layup so they can offer a limited warranty on hull blistering. I am not aware of any vinylester based barrier coat products. Of course vinylester is available as just a resin but in my observations it's use has primarily been in layup work. Additionaly vinylester would be a thinner mix than the epoxy and would require more applications to acheive a suitable build-up thickness. Not to mention the difficulty of use that you pointed out.

Please post additional info on vinylester testing results if you have it.It would be interesting to read about it's testing performance.

Vinylester is the most water proof coating you can put on a hull...superior even to epoxy for its MEE (Moisture Exclusion Effectiveness)BUT it's trickier to use. The product has a short shelf life so it must be fresh...buy it from a reputable supplier. Mix small batches at a time and use a foam roller to apply. It hardens a lot quicker than epoxy which can be a double edged sword. Keeping track of the number of coats and where you stop/start each successive coat on the hull. Keep recoating until the desired thickness is achieved. I used a grease penci on the top sides to keep track of my progress and number of successive coats. Vinylester doesn't sand as well as epoxy either. But it does prevent blisters better than any other product.
I believe the previous posting was talking about polyester resin which is widely used to layup fiberglass. Polyester resisn has worse MEE than either epoxy or vinylester and should never be used as a barrier coat.

[Fred]

Kurt,

If you know of a source where I can read about the tested effectivness of moisture exclusion and penetration resistance between the the vinylester and the epoxy resins then I would like to read it. If indeed there is a much better performance of the vinylester that I'm not aware of then I want to know about it. In my readings I have come across nothing that makes that claim. Some hull manufacturers are using vinylester for layup so they can offer a limited warranty on hull blistering. I am not aware of any vinylester based barrier coat products. Of course vinylester is available as just a resin but in my observations it's use has primarily been in layup work. Additionaly vinylester would be a thinner mix than the epoxy and would require more applications to acheive a suitable build-up thickness. Not to mention the difficulty of use that you pointed out.

Please post additional info on vinylester testing results if you have it.It would be interesting to read about it's testing performance.

Vinylester is the most water proof coating you can put on a hull...superior even to epoxy for its MEE (Moisture Exclusion Effectiveness)BUT it's trickier to use. The product has a short shelf life so it must be fresh...buy it from a reputable supplier. Mix small batches at a time and use a foam roller to apply. It hardens a lot quicker than epoxy which can be a double edged sword. Keeping track of the number of coats and where you stop/start each successive coat on the hull. Keep recoating until the desired thickness is achieved. I used a grease penci on the top sides to keep track of my progress and number of successive coats. Vinylester doesn't sand as well as epoxy either. But it does prevent blisters better than any other product.
I believe the previous posting was talking about polyester resin which is widely used to layup fiberglass. Polyester resisn has worse MEE than either epoxy or vinylester and should never be used as a barrier coat.

John, 3m made a v-ester barrier coat product as of a couple years ago. They may still make it.



fred@hotsheet.com

[Kurt]

I believe it was an article in Practical Sailor where I first read about the MEE factors of various bottom coatings. Vinylester is best and pure epoxy resin is 2nd best. Epoxy is easier to use and has been used successfully on many hulls. But since the first posting in this series asked which product is best...I mentioned the vinylester.
On my CD26 I used epoxy on most of the bottom but still continued to experience blisters at the waterline. I had removed the gelcoat on the hull but merely feathered it at the waterline. So I bought a quart of vinylester, recoated the waterline area and haven't had a blister since. 3M introduced their vinylester coatings the year AFTER I did my repair job. 3M has since removed the vinylester resin from their product line because (are you ready for this)...it was too expensive to man the #800 customer service phone because so many consumers had questions. I will also mention the Interlux Interprotect 2000 faired rather poorly in the MEE tests...the VC17 wasn't very good either. Avoid any products that contain dryers and additives.



kjlgpw@aol.com

[Kurt]

I believe the Practical Sailor article and testing occured in the early 90's

[John R.]

I believe the Practical Sailor article and testing occured in the early 90's

Hey guys wait a second here. Since when have the guys at Practical Sailor become chemists and have a suitable testing facility and the knowledge to make such conclusions. They aren't professionals or experts in that field. Just like we aren't. They're just a group of sailors. Second of all they simply are not going to take the time or make the effort to really test a barrier coat. It is too complex of a set of circumstances that has to be dealt with. It should only be done by a highly experienced lab or by a study of test vessels over a long period of time.

Any of us with any experience under our belt know full well that Practical Sailor makes more than their share of poor evaluations and conclusions on various equipment and materials. When it comes to things like bottom paint, brightwork coatings, barrier coats, anchoring systems, and various equipment we are best served by our own judgements and experiences of others over the long haul. That proves to be far more valuable than a quick test by the PS guys.

I admit I don't know how they conducted their testing but simply coating a couple pieces of glass and subjecting them to moisture resistance would not be what I'd call a suitable demonstration of effectiveness. That is typically how their testing is done. I would want to know how this or that coating works on different hulls. Epoxy has had an excellent track record including Interlux Interprotect 2000. I have rarely seen it or West fail if proper hull drying and preparation are done according to directions. I'd love to read about professional lab testing of vinylester vs epoxy. If anyone knows of a link on that topic please post it. Do you guys really believe the 3M 800 number cost is why they discontinued the vinylester products. I would bet they discovered the epoxy was the way to go.