Epoxy vs MAS

[Greg Luckett]

I have heard that Devlin uses MAS exclusively now and this caused me to consider it. It looks like MAS cost about 30% or so more than epoxy, which is already expensive as it is. Why use MAS?

Opinions and/or discussion please.

[Pipefitter]

I know alot of people have had different success/failures in regards to brand names vs. generic equivalents but I have tried several of the different brands and on the same boat.The only difference,being that epoxy is really overkill as an adhesive on wood for a boat,is being used to what you are working with. Any of the epoxies that saturate cloths effectively are going to have solvents in them. I found no difference in the brands other than amine blush issues. Did that matter? No. Why? Because no matter what the makers claim about amine blush or the lack of,you would still be wise to clean it as it blushed the worse.Are you going to believe the claims and not clean/sand the surfaces thoroughly?Ofcourse not. I bought the generic(about half priced of a popular brand) equivalent

epoxy and it performed flawlessly. I have drops of epoxy primed ply outside now for 2 years to the weather and it has not budged.

Waterproofing: My boat was built outside. During the hurricanes,I had to take the tent cover off and cover the boat with a polytarp instead and it did get water in the boat. About 4" in the bilge that I didn't catch for a whole week because I didn't think that much water had gotten in there. There was no discoloration of the ply under the epoxy where the water was sitting. If the epoxy hardens and builds to a solid film,it is epoxy as epoxy gets. It's all formulated from the same basic chemicals from not so many suppliers and just formulated for different performance.

I even made my own penetrating epoxy with the generic epoxy, thinned with interlux's epoxy primer thinner 2333n.This stuff soaked in forever mixed at about 40% epoxy/thinner. Look at the coated wood under a magnifying glass with the different brands.It all looks the same.The best bet, is to not believe so much of the hype and just use it with common sense and maintain your boat like it doesn't have anything on it at all no matter what they claim. You are better off,to be able to afford extra volumes of the cheaper to be sure that you have enough to not have to skimp or chance dry glue/layups because you only have "just enough".

[Greg Luckett]

This is interesting insights to epoxy. Thanks Pipefitter.

What I am trying to understand is the MAS stuff being used instead of epoxy. I went to a website where they sell and explain the MAS, which is another type of resin...from what I gathered last week.

[Ken_Potts]

I have heard of MAS but not used it (so this isn't going to be a particularly helpful post ) - I have assumed MAS was a brand name of epoxy. Consequently I am now very interested to hear what MAS is - I'll surf the web some at lunchtime tomorrow but in the meantime there must be at least one insomniac chemist on the forum who would like to write a layman's primer on the subject.

I sat at lunch one day (Lamb Vindaloo - Mmmm...) with a couple of friends - A chemist and a materials scientist - Who were comparing notes on how one would go about creating epoxy from materials available at, say, a supermarket. I was very interested in the idea but unfortunately they were engaged in that chemist speak that is half math and half cipher. I heard a lot about exothermic and endothermic thingies and covalent shells and hydrogen bonds but all I took away from the experience was this dumb story and that something like aspirin might be useful Sorry...

[Pipefitter]

Epoxy,MAS,whatever should not be treated differently from a adhesion/protection standpoint, any further than a minimal primer.It's just a damned good one.Get some of the sample kits from different suppliers and conduct your own tests. I bet you find that it isn't false economy to use a more fairly priced product in terms of performance and longevity/durability.It's going to do the job and will not cut down on any maintenence that you would normally have to address. Is there really any noticeable difference? If you can build a boat,you can surely overcome any slight difference in coatings quality. I still feel it is more important to be able to afford more than enough needed to allow for adequate application.

[Charlie Jones]

Greg- MAS IS epoxy. It's a 2 to 1 mix rather than a 5 to 1 like WEST. Raka is another 2 to 1 epoxy. I've used all three. All are good, but MAS cures WAY slower than WEST in cooler weather. Over about 80 degrees they are about the same, but under about 60 the MAS will take two to three days to reach workable cure where the WEST can be worked in 24 hours. MAS also smells just a little better than WEST .

RAKA is a slower cure in cool weather also, but not as slow as MAS. If you want to use it up where you are, plan to do it summertime, or plan to wait a while between glueups unless you can really control the temps where you are working..

Amine blush is no biggie- it's totally water soluble and just a quick wash down gets rid of it. In hot weather it seldom appears, but I wash 'em all down anyway unless I'm hot coating.

[Pipefitter]

I used US composites.They had different speeds of hardener. I liked the slow hardener(2 to1) for glass work,medium 1 to 1 ratio thick epoxy for glue joints. I just made sure I had my working schedule set up effectively. I had a day or 2 worth of work on other parts incase of a slow cure. Even in colder weather though,the difference was hrs over days but I am in a more mild climate other than the humidity factor. I would use this again. The 1 to 1 thick also worked on the thread wraps on a fishing rod rebuild where I would have normally used flex coat rod builders epoxy. In no way am I claiming that the name brands are bad but I do think they are rediculously overpriced. 5 to 1 is an expensive mix/volume. I also prefer the 2 to 1 systems. I guess it really depends on what you can justifiably afford. I would also like to add that from a build to sell standpoint,that it might be better to use a name brand for buyer confidence/selling issues.

[boatbuilder.org]

MAS is a brand of epoxy. It was developed by two guys that wanted to make a safer epoxy to use. The choice of diluents used in MAS epoxy to make it a low viscosity resin are chosen with safety in mind. The word "solvent" is a catch phrase for bad stuff, keep in mind that water is a solvent also. True non blushing hardeners does eliminate the need to clean the surfaces which will give you a window of time that re coating with more epoxy can be done with out any prep. If the MAS epoxy has fully cured it will however need to be sanded before another application of epoxy primer or paint. MAS slow hardener is a non blushing hardener, the medium hardener is extremely resistant to blush. It may occur in very cold and high humidity conditions. The new fast hardener, just recently modified, is also extremely resistant to blush.

The chemist at MAS is trying to make an easy product to use and keep the possibility of becoming sensitized to a minimum. I have used WEST, System Three, RAKA and MAS and I prefer to work with the MAS over the others.

---Joel---

[Guest Oyster]

There is not much I can add addressing the chemical part of epoxy and its complimenting items. But overtime there is not much that I have not tried in multiple conditions, which seems to be more of an issue than anything else with epoxy. When using epoxy, as an occasional user, on one project, or even two, the primary issue that is important to keep in mind, from my perspective boils down to two issues. The very first issue is the viscosity of the epoxy resin.

This seems to have more of an adverse effect of the overall job for the amateur, newcomer or occasional user, if proper wetout and satuation does not take place. The ambient temperature is so important in combination to the brands as it comes in the package. I do not feel that the differences in the many brands of epoxy, that is being sold over the counteris so drastic, that makes one have a edge with the same set of circumstances.

I personally view this from hinesight, both in rush jobs, :wink: and by speaking with some boat plan builders and looking at some of the failures. The two to one mix, in most cases is still the best unless its just a small part to be glued or coated. And make sure that your resin is not hard molasses. You do not want to see resin in the form of a heavy drip from a leaky faucet, and use this as a guide for resin viscosity. Think about the squeeze honey jugs, or maple syrup jugs, and do not use the resin if its not as runny as this when placing it on those premade waffles. Of course this can also be acheived by surrounding the jugs or cans with lights or heat, or by storing it inside. Bear in mind, too, that the surface needs to be somewhat warm too.

The second most important thing that I consider to be very relevant to learning to use any epoxy, of course is the hardener for the job. This one portion of the equation seems to be overlooked in the rush for what is known as instant gratification for a completed project or portion of a product, when people have a limited time to work on projects after work or on weekends, and four season climate areas of the world.

Patience must be adhered to in all of these projects, especially when boat plans incorporate fiberglass as part of its makeup for the struture, unlike skin coats for abrasion or finish work coatings.

Yes I am preaching to the choir here in most of the comments, but with less to contribute in this one, I am just typing as I have had too many cups of coffee. :wink:

[Pipefitter]

That about says it,Oyster. Is pretty much what I meant about if someone can build a boat,they have the mindset to make and understand what works via the common sense comments.Also in agreement about storing the thicker mixes indoors. I used to set the jug of the thick stuff in hot water before using it if it was cool out. And if it wont come thru the pump,it is too thick.I used the one to one on wood joints so that my glue wasn't mostly filler/thickener powders.I did have to learn how and where to use it and I did some trials on scraps first to be sure. I also asked the supplier if there was compatibility issues if I primed the dry joints with thinner epoxy first and I could initially tell by how informative the supplier was which also let me know they had confidence/knowledge in what they were selling to me. After about a fourth of the way thru the project,I found I wasn't getting any on myself or my shoes(tops of them) anymore.

[Tom Lathrop]

I have used WEST, Chem Tech, System 3, MAS, Fiberglass Coatings, LBI, RAKA and a couple other less known industrial epoxies. For the home builder, there is little difference in performance among these. Some are lower viscosity which makes for easier wetting out of cloth. Some like the old Chem Tech adhesive were so viscous that it wore out my wrist to mix so I won't use them. WEST's 5 to 1 ratio makes mixing small batches iffy unless you have a WEST dispenser pump (expensive). The high ratios tend to be stronger in industrial use (controlled conditions and heat) but all the above epoxies are more than strong enough for use in boats.

I and most in this area now use RAKA for economy, excellent packaging and service from the supplier. The commercial builders of sportfishermen on this coast and Outer Banks mostly use other brands that they get cheaper in very large quantities. If you are building high end boats (read expensive) where the cost of the epoxy is not a large fraction of the selling price and the customer can be impressed with the fact that you use the "best" (read most expensive) products, then it may be in your best interest to use those.

If you are a home builder on a budget of ,say, $5000 and trying to keep cost down, it's a different story. The largest expenses in a composite wood boat are the wood and the epoxy, not counting the engine or sail & rigging. In this case where you might need 25 to 30 gallons of epoxy, you might save $1000 or more by choosing RAKA or FGCI over the high price brands. That is a big chunk of the budget for the home builder and if it takes a bit more effort or time to wet out some glass sheathing, so what.

There are still some of the complexities brought out by the posters above to be considered but there is a personal learning curve to all boatbuilding.

[Pipefitter]

Again,Tom, the points you just hit on is the same feeling I had gotten when talking to the supplier and what I had understood about the bulk of who they supply to. Their information gave me the feeling they were used to dealing with professionals who knew what they needed. If they have been in business for as long,someone must find their prices/quality satisfactory.That about sums it up.

I did find about half way thru,being my first boat/epoxy trial,that I was glad to be able to afford enough volume to learn with and have enough for everything else. And to not break the bank if I had mixed too much for the task,etc.

[boatbuilder.org]

Although I do prefer to use MAS, and even sell the stuff, I think that for the home boat builder all the epoxy brands listed in this thread work fine for home built boats. If you get into exotic carbon fiber epoxy infused blah blah blah applications I am sure there would be noticeable strengths and weaknesses of the various brands but for home built boats, that are generally overbuilt anyway, I don't think the differences are noticeable in the finished product. I base my preference on the ease of use of the system.

---Joel---

[capt jake]

I also have recently been introduced to MAS. I find using it, comparible to Raka. I prefer either over West (viscosity, ease of use, price).

I also find it useful to know that you can bleand the hardners to achieve a moderate rate of cure (over straight Fast or straight Slow).

MAS seems to cure fully and completely in the applications I have used it.

[Greg Luckett]

Ok, lots of good info in this thread. Thanks to all.

I am still puzzling about why MAS is worth the extra 30% over West Systems, for instance. Is it really that much safer an epoxy? Does ist cover more area thus making it more equal, etc.

Pipefitter, I think you are missing the point I am trying to make since you keep going back to the justifications (almost a rant?) of prices vs. quality...or I am missing what you are trying to get across to me? I am not questioning spending money for quality. I am asking why MAS is preferred by a boat builder such as Devlin over other epoxies? You have not said...or I missed it....that MAS is a superior epoxy. I could of course buy samples of all the epoxies to run testing as you have suggested, and I have done things like that in the past, but one of the things I have found of great value here on this forum is the wealth of already existing knowledge. Why re-invent the wheel?

I think Joel and Charlie hit closest to answering my question....MAS is safer to work with with regard to physical considerations. This would make it easy to justify the extra expense, but then I wonder how much safer it actually is? Is this the reason Devlin uses it exclusively now, or are they also getting significant discounts for volume, which would make it more economically justifyable from a business sense.

I will re-read this msg thread after I get some rest as there is a great deal of information here to absorb completely. Thanks again to all of you!

[capt jake]

You must be getting a real bargain on West. I find it to be 30-40% higher than Raka and about 20% more than MAS. I find the same with System Three and it is made very local to me.

Go to Joel's site, he is having a sale of sorts there.

[Greg Luckett]

Although I do prefer to use MAS' date=' and even sell the stuff, I think that for the home boat builder all the epoxy brands listed in this thread work fine for home built boats. If you get into exotic carbon fiber epoxy infused blah blah blah applications I am sure there would be noticeable strengths and weaknesses of the various brands but for home built boats, that are generally overbuilt anyway, I don't think the differences are noticeable in the finished product. I base my preference on the ease of use of the system.

---Joel---[/quote']

Joel, your comment about ease of use just entered my fuzzy awareness (I really need to get more sleep). In what ways is it easier? I also note that you sell it, which means you are buying at wholesale prices. How do you market it.....or how can I purchase it from you?

Thanks.

[Greg Luckett]

You must be getting a real bargain on West. I find it to be 30-40% higher than Raka and about 20% more than MAS. I find the same with System Three and it is made very local to me.

Go to Joel's site' date=' he is having a sale of sorts there.[/quote']

West Systems 105 is $75/gal, fast hardner 205 is $29, just bought some more last weekend. That price on the hardner jumped about $5, and the resin about $5 since last fall when I bought a couple of gallons. If I start buying wholesale via West Marine, it drops the price more, but I am not judging on wholesale deals at this point.

The MAS Flag resin is $47 per 1/2g, plus the Low Viscosity resin is $47 per 1/2g, then the hardner is $54 per 1/2 gal. It looks like both would be needed to do what the West 105 does. Add on the shipping cost...I do not know yet what that would be. These prices are close but the MAS is going to cost more due to having to use two different resins. It makes it a little harder to compare the pricing. I agree, the 30% difference is not there unless you compare the retail to wholesale pricing, which would not be fair. When I first looked at the costing I was thinking of 1 gal increments, then it occured to me that since the MAS is 1:1, which would make 2 gallons, I needed to divide by 2 to get the price per gallon. The West System is really .96 gallon plus 1 qt hardner, so it is still less expensive than the MAS, but not by 30%. Maybe about 5%?

[Greg Luckett]

Wow, Joel has much better pricing. Thanks Capt. Jake!

Do you include shipping cost when you compare epoxy prices?

[capt jake]

MAS Flag resin is a thicker resin for laminating. I am not sure if it is 2:1 or 1:1, but I believe it is 2:1. The Flag is more expensive than their standard low viscosity resin.

My way of thinking is to get the low vis and make it thicker if I need to. No sense in having a thicker resin around for only a few applications when I can use one resin to do both.