Resin type for resto

Gpayne

Petty Officer 3rd Class
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May 28, 2012
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75
Quick question, and I'm sure it's been covered many, many times before. I'm planning on starting a complete resto of an 18' FG open bow this fall. What would be better to use? Epoxy resin or poly? I know each has to be used with it's own specific type of mat, and each has it's own pro's and con's. I'm just looking for opinions. Pros/cons of each, other than the obvious financial pros of poly. Any input would be much appreciated, thanks guys!!
 

GT1000000

Rear Admiral
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Jul 13, 2011
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Re: Resin type for resto

Stick with whatever the boat was constructed with originally...
 

Gpayne

Petty Officer 3rd Class
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May 28, 2012
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Re: Resin type for resto

OK, dumb question, but how do you tell what was originally used?
 

jigngrub

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Re: Resin type for resto

More than likely it was poly for production cost savings.
 

GT1000000

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Re: Resin type for resto

The only dumb question is the one never asked, then you screw up for not asking...;)
If it is a fiberglass boat, it is almost certainly made with Polyurethane Resin...not epoxy resin...sticking with what it was originally made with, makes the restoration a lot easier...you don't have to worry about compatibility issues...

I could be wrong, and this boat was made using epoxy, but from my limited knowledge about boats, epoxy is almost always used on higher end boats, like yachts or racing type hulls...it is also use when replacing the wood structures on aluminum boats, because it is much easier to work with and much less is used/needed...

Epoxy does have certain advantages, the longer curing times can help in getting certain things properly positioned, it does waterproof when properly done, tends to have less health issues than poly...
 

Bondo

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Re: Resin type for resto

The only dumb question is the one never asked, then you screw up for not asking...;)
If it is a fiberglass boat, it is almost certainly made with Polyurethane Resin...not epoxy resin...sticking with what it was originally made with, makes the restoration a lot easier...you don't have to worry about compatibility issues...

I could be wrong, and this boat was made using epoxy, but from my limited knowledge about boats, epoxy is almost always used on higher end boats, like yachts or racing type hulls...it is also use when replacing the wood structures on aluminum boats, because it is much easier to work with and much less is used/needed...

Epoxy does have certain advantages, the longer curing times can help in getting certain things properly positioned, it does waterproof when properly done, tends to have less health issues than poly...

Ayuh,... moot point, but it's Polyester, not polyurethane..
 

Yacht Dr.

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Feb 26, 2005
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5,581
Re: Resin type for resto

Good poly resin will be just fine in a partial or total rebuild..

YD.
 

tpenfield

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Re: Resin type for resto

OK, just to muddy the waters . . . How about Vinyl Ester resin?
 

ondarvr

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Apr 6, 2005
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Re: Resin type for resto

Epoxy does have certain advantages and tends to have less health issues than poly...

Not to pick on you, but epoxy can have severe health issues from even slight exposure, polyester rarely has anything more than slight temporary irritation.

Polyester does tend to have a much stronger odor though, this makes people think it's more hazardous.
 

GT1000000

Rear Admiral
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Re: Resin type for resto

Not to pick on you, but epoxy can have severe health issues from even slight exposure, polyester rarely has anything more than slight temporary irritation.

Polyester does tend to have a much stronger odor though, this makes people think it's more hazardous.

Thanks for clearing that up, I may have misspoken here...

Upon further research on my part...however flawed or unreliable it may be...:facepalm:

I have come across sites that show the two products to be quite similar in their health risks...some more, some less

These are two of the many sources on the net that I looked through...

http://www.fibreglass.com/MSDS PDF/Poly Resin.pdf

http://www.westsystem.com/ss/assets/MSDS/MSDS105.pdf

I guess it depends on the who's doing the research and the exact chemical make-up of the product.

I humbly apologize for inserting my lower appendage in my pie-hole...:redface:
 

ondarvr

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11,527
Re: Resin type for resto

Here is more info from the West System site, it was too big to include more.

Of the thousands of people I've come in contact with that use polyesters on a daily basis I know of none that have any type of a nasty reaction when exposed to polyester (there can be some irritation though). The number of people I meet that use epoxy frequently is far fewer, but I know many that have various levels of reactions from mild to more severe with even incidental contact after they've became sensitized to it.

You Are Here: Home ? General Safety Guidelines ? Health Effects from Overexposure to Epoxy
Health Effects from Overexposure to Epoxy
We have a long history of working with and around epoxies daily. As builders and epoxy manufacturers, we’ve had a much higher risk of exposure to epoxy than the average builder or casual epoxy user. Through our own experience, and the experience of other builders, we can estimate the likelihood of health problems from handling WEST SYSTEM resins and hardeners.
The following are the most common health problems stemming from epoxy use. Nearly all of us can prevent these problems. The majority of those who do develop a health problem can continue using epoxy with adequate precautions.
Dermatitis
Fewer than 10% of epoxy users react when overexposed to epoxy resin or hardener. The most common reaction is contact dermatitis, or skin inflammation. Both epoxy resin and hardener can cause acute contact dermatitis. Discomfort can be severe, but usually disappears after stopping contact with the irritant. Repeated skin contact with resins and hardeners may also cause chronic contact dermatitis, which is usually milder but longer lasting. If left untreated for long periods it can progress to eczema, a form of dermatitis that can include swelling, blisters and itching. Partially cured epoxy sanding dust, if allowed to settle on the skin, can also lead to contact dermatitis.
Allergic Dermatitis (Sensitization)
Allergic dermatitis is a more serious problem, but less than 2% of epoxy users are likely to get it. Allergic dermatitis is when the body hyperreacts to an allergen. Sensitization is the condition of being allergic to a substance. Your immune system and the degree and frequency of exposure to epoxy affects your chance of becoming sensitized. You are most susceptible if you have been grossly overexposed to epoxy or if you are inherently sensitized or allergic to a component of epoxy. You are also more susceptible if you have fair skin, if you’ve already been exposed to other sensitizing substances, or if you have hay fever, other allergies or are under stress.
You may become sensitized to epoxy after many exposures or just one. It could take ten days of exposure, a month, or even years. It is best to avoid all exposure because you cannot know ahead of time how much you can tolerate before you become allergic.

Allergic reactions to epoxy can result in irritated skin or respiratory problems. Irritated skin is by far the more common of the two. Usually, it appears much like a reaction to poison ivy and may include swelling, itching and red eyes. Just as with poison ivy, the irritation can be mild or severe, acute or chronic.

Inhaling concentrated epoxy vapors, if done frequently or for long periods, can irritate your respiratory tract. Exposing sensitive skin areas, like the eyelids, to highly concentrated epoxy vapors may cause itching and swelling.

See a physician if irritation persists or worsens after avoiding epoxy for several days. There is no specific antidote for epoxy sensitization, but symptoms can sometimes be treated with medicine.

Once sensitized, additional (and sometimes increasingly severe) reactions become likely upon future exposures, even to tiny amounts of epoxy. It is difficult, but not impossible to prevent recurrences. Resume epoxy use only after symptoms disappear, and strictly follow the recommended handling procedures to prevent exposure. Read the product’s material safety data sheets (MSDS) so you can identify symptoms and employ preventive and first aid measures.
Severe Irritation and Chemical Burns
Hardener burns are uncommon. Mixed epoxy is unlikely to cause burns. By themselves, WEST SYSTEM and PRO-SET epoxy hardeners are moderately corrosive. If left in contact with the skin, they can severely irritate it and cause moderate chemical burns. Chemical burns develop gradually, and first cause irritation and slight pain. The burn may discolor and slightly scar the skin. The time it takes for a hardener to cause a chemical burn depends on the area of contact and hardener concentration. When resin and hardener are mixed, the hardener is diluted and therefore less corrosive. Although mixed epoxy is less corrosive, never leave it on your skin. It cures rapidly and is difficult to remove.
Respiratory Irritation
Breathing highly concentrated epoxy vapor can irritate the respiratory system and cause sensitization. At room temperature, epoxy vapors are unlikely to be highly concentrated. However, if you are already sensitized to epoxy, exposure to low concentrations of epoxy vapors can trigger an allergic reaction. At warmer temperatures and in unventilated spaces, the epoxy vapor levels increase.
Never breathe the sanding dust of partially cured epoxy. Epoxy chemicals remain reactive until they have cured. Serious health problems can result from sanding epoxy before it is fully cured. When you inhale these dust particles, they become trapped in the mucus lining of your respiratory system. The reactive material can cause severe respiratory irritation and/or respiratory allergies.

WEST SYSTEM fillers present few hazards by themselves. However, breathing any nuisance dust will worsen existing respiratory problems. Smokers and others whose lungs are under strain are far more likely to develop serious respiratory problems.
 

gatorfan6908

Petty Officer 2nd Class
Joined
May 17, 2010
Messages
149
Re: Resin type for resto

Gpayne,
I am no expert on the subject of fiberglass and resins, but I have done quite a bit of research and I have concluded that for more low-end restores, polyester is best suited for the job. This typically deals with a better cost efficiency and less worry about adhesiveness to other glass on a boat. It is also more user friendly from what I have read as well, which is what I am looking for with my first restoration project. Whichever your choice, I hope the best for your project and that it all goes well! As I am sure that you already know, there are plenty of threads in these forums which can give you all the info you need on both types of resins. Best of luck!

Lonnie
 
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