Epoxy Resin

[Pull-doo]

I am rather new to wooden boat building and have questions about epoxy resin. First what is it? I use 2-part epoxy glue all the time, is this the same? Why would I use epoxy resin over fiberglass resin to cover my boat, is epoxy stronger? I have seen marine epoxy at Home Depot and it is 4-times the price of fiberglass so I am really interested in understanding the difference. Finally, if I must use epoxy resin, where can I get it cheaper than Home Depot?

[cs]

Let me be the first of what will probably be many replies.

First "fiberglass" if I'm not mistaken refers the the actual cloth. There are several types of resin to imbed this cloth in. There is epoxy, polyester, and vinylester that I know of. Your production fiberglass boats use a polyester resin. The problem with polyester is it don't adhere to wood good. If used you may have problems with delamination. Also poysester does not adhere to epoxy either. When using polyester resin you leave yourself open to delamination, water penetration, and blisters and others.

Epoxy on the other sticks to anything and is resistant to water penatration. Epoxy also creates a bond that is stronger than wood and can also be used as a faring compound or a glue.

I've no expeirance with vinylester.

As far as price, yes it is expensive. I've used name brands and off brands and even the stuff you find at Home Depot (Bondo brand). I found that the most bang for your buck is through RAKA at:

http://www.raka.com/

If you are using fiberglass in conjuction with wood you really want to use an epoxy resin. BTW yes it is about the same stuff as your 2 part epoxy glue.

Chad

[Bruce Hooke]

To add to what Chad said, while marine epoxy is basically the same as whatever other epoxy you have been using there are many formulations of epoxy with widely varying properties for varying purposes so I would strongly recommend that for boatbuilding you use an epoxy sold for that purpose (Raka, West Systems, and System3 are three common ones). You also need to be careful on the fiberglass cloth because it is treated differently for epoxy vs. polyester resin. The stuff made for epoxy will work better with epoxy, but you need to look a bit harder for it because the stuff sold in most non-boat related stores is for polyester resin.

Even if you don't use West System epoxy I highly recommend their book on the epoxy & boatbuilding. It will provide all sorts of important details and help you avoid the many pitfalls that otherwise await you :D

You can even get it from our sponsor:

http://www.woodenboatstore.com/store/images/300056S.JPG

[Pull-doo]

I should have said fiberglass resin. They sell Bondo brand fiberglass resin at Home Depot and many other places. Its about 20 bucks a gallon. So what is this, polyester? Is it not good to use on the hull?
Thanks for the URL to RAKA.

I am in Houston TX where it is hot as @$#*! So is the epoxy resin effected by heat like the fiberglass resin? In the heat fiberglass resin sets up real fast. At the prices I am seeing for epoxy I can't afford for a batch to harden on me before I get it all on the boat.

[NormMessinger]

Polyester stinks! If you are married and want to stay that way don't use polyester around the house, in the garage,....

Oh, and what was said above. Especially what was said above!

"The Epoxy Book" published by System Three is free for download http://www.systemthree.com/index.html . At the least, read it.

My epoxy bias is that the main stream brands, System Three, WEST and perhaps MAS are forumlated to work at the extremes whereas the cheaper versions will work just as well, it is said, at optimum conditions.

Check epoxy prices from Hamilton Marine, West Marine, direct from the maker, etc.

"The Epoxy Book" will answer most of your question. For the others, come back here for a variety of opinions.

--Norm

[thechemist]

Different manufacturers make different epoxy formulations, which have different properties.

Some have different mixing ratios, ranging from one-to-one by volume to five-to-one. The one-to-one are usually the most tolerant of small mixing ratio errors. All must be thoroughly mixed before use.

Some are more-or-less flexible when cured. This may or may not be a good thing, depending on what you are doing with it.

Some glue oily hardwoods better than others.

Some "go off" faster or slower, and this depends on how the product was formulated. You cannot get good results by adding more-or-less of the "hardener". Epoxy products generally require a certain fixed proportion of part A to part B, and deviating too far from this will give a goo that never cures, and you may come to be called goody-two-shoes because they are both stuck to your floor.

[paul oman]

Hello:

I put together a primer on epoxies you might like to view

http://www.epoxyproducts.com/25points4u.html

I know about the Houston heat in the summers, we moved to NH 18 months ago from Houston (Pearland) to get away from that heat!

Paul

[Wayne Jeffers]

Pull-doo,

Please note: There is no such thing as fiberglass resin. Fiberglass is the cloth or matt which is used in the composite GRP, or glass reinforced plastic, commonly referred to as fiberglass.

The resin (a thermoplastic) is one of the ones Chad mentioned, probably polyester.

It's important to distinguish between the fiber used and the resin used.

Wayne

[ 07-12-2002, 06:42 PM: Message edited by: Wayne Jeffers ]

[stan v]

Pull-doo, welcome to the board. I just crawled out of the boat, epoxied new window frames. The slow hardener I mixed (you have to use the ratio you select, not like polyester where you can adjust hardener to have the desired pot life) started kicking in less than 10 minutes! Hot as blazes in that tin shed, so you must use the slow hardener in Houston during summer. I use www.fgci.com, (http://www.fgci.com,) they are in Florida and I highly recommend them for service and the quality of material. About $35 a gallon, and MDS reads likes West. You won't believe how strong this stuff is when used with cloth/biaxial.

[Charlie J]

I'm just down Hwy 59 from you in Victoria and it's just as hot here( or hotter) and I use epoxy all the time.

Just mix small batches so you can use it up before it kicks, and use slow hardener. WEST does make a "tropical" formula, which mixes at a different ratio for extremely hot weather. Personally I've never found the need for it.

If you are glassing over wood, use some brand of epoxy. They're all pretty good, just find one you like and stick with it till you learn what it'll do.

[Pull-doo]

Thanks to all who responded. Great info from everyone. As I said, I am new to this and have quite a bit of learning to do. You guys just took me way up the curve though and I feel like I know enough to get started. Thanks again, to all.

[Roger Stouff]

Pull-doo, you must be a duck hunter, eh? :)I wonder if that term is just regional? Guys?

Greetings from south Louisiana (where we know what a Pull-doo is, too!)

Roger Stouff

[Bruce Hooke]

Since it looks like no one really answered your question about the Bondo stuff at Home Depot I will just jump in here and note that, Yes, that is polyester resin (they may sell it as "fiberglass resin", which as Wayne noted is incorrect, but terminology has never stopped the marketing folks!). In any case, polyster resin does not stick very well at all too wood so while some people manage to use it around wood boats epoxy is really a much better way to go. Epoxy is, unfortunately, as you have seen, much more expensive that polyester. It does set up faster in hot weather too. Some epoxy makers sell slow hardeners to help counteract this problem. I believe West System (http://www.westsystem.com) sells something called Tropical Hardener, but I have never looked at it in detail because heat is less of an issue up here in Rhode Island. Also, if you can do your epoxy work in the shade and earlier in the day that will help.

[Cedarhill Boatworks]

The key to extending pot life is to spread the mixed epoxy out. Think surface area. If you mix a pint of epoxy in a coffee can it will have a shorter pot life than if you mixed the same amount and dumped it into a roller pan. The curing epoxy generates heat, enough heat to burst into flames under the right conditions, if you dissipate that heat the cure time is extended. A plastic beer cup in a coffee can full of ice cubes makes a nice container in a hot confined space. Once the ice melts, and the heat builds up the epoxy does in fact burst into flames. Yell as loud as you can, with lots of profanity and try to throw the burning mess out of the shop......

[Pull-doo]

Roger - Yes, definitely a duck hunter, actually I am obsessed with hunting ducks but that's another story. I was raised not far from your neck of the woods in Beaumont, TX. Living in Houston right now. I knew em as a pull-doo long before I heard them called a Coot. Maybe it is regional.

I love south Louisiana and I especially love to hunt ducks there. There are alot of Cajuns in Beaumont you know. I have a lot of Cajun friends, Broussard, Benoit, Fontenot, Thibideaux, Hebert (A-Bear). Now and then they take me to Louisiana and we shoot dem duck and pull-doos with our relmington twice-hole gun shoots.

[Pull-doo]

Ok cedarhill you just scared me. You were joking, right? I know epoxies get really hot when mixed, but flames I don't want. So what is the best thing to do, mix 8 oz., maybe 16 oz. at a time? Are you saying I should dump it on the surface all at once and then spread it around?

[ 07-16-2002, 04:35 PM: Message edited by: Pull-doo ]

[Cedarhill Boatworks]

Don't be scared. It's really very simple. If you have a lot of resin to mix and spread the idea is to mix it well and then keep it in a container that exposes as much surface area as possible. The idea is to not concentrate the goop in a confined space. IE a coffee can or a pot. If you can stay out of direct sunlight and work during the cooler hours of the day all the better. Use a slow cure hardner. Remember think surface area.

[Wayne Jeffers]

Figure you'll have between 10 minutes and 30 minutes to spread the epoxy before it kicks. Depending upon what you're doing, 8 ounces is one heck of a lot. Start with two or three ounces if you're brushing it on. If you're laminating and using a roller or squeegee to saturate glass cloth, 8 ounces is on the high side of what you can probably use before it kicks.

I like the MAS epoxy with blush-free slow hardener for wetting out cloth. I've had good results with FGCI 1:1 laminating resin, too.

Wayne

[Cedarhill Boatworks]

Wayne,

have you used a lot of MAS? I have never used anything but West, but it is getting harder and harder to find locally. All of the distributors around here are stocking MAS these days. I don't use a lot so it doesn't pay to buy bulk.
Anybody else? What do you think of MAS vs West?

[Wayne Jeffers]

Cedarhill,

I'm using MAS now for the first time, with Slow hardener. I've never used West, so I can't compare.

In small batches, I get at least 45 minutes working time. (My shop is cool, even in hot weather. Low 70's.) It's very thin and wets out cloth quickly. For a commercial shop, you might find it too slow to cure, depending on how you work. I sometimes find that I'm waiting for epoxy to fully cure, but it doesn't much matter for my hobby. I first used it in the spring, at about 50 degrees, and it took days to cure with the slow hardener.

Wayne

[Pull-doo]

You guys have suggested some really good distributors of epoxy that are available online. Can anyone give some examples of the types of places where I might find these products locally. My Home Depot and Lowes do not have any, and I want good product. Should it be necessarily difficult to find it locally? Houston is a big town, surely there are places that have what I need.

[Nicholas Carey]

Originally posted by Pull-doo:
Ok cedarhill you just scared me. You were joking, right? I know epoxies get really hot when mixed, but flames I don't want. So what is the best thing to do, mix 8 oz., maybe 16 oz. at a time? Are you saying I should dump it on the surface all at once and then spread it around?Get The Epoxy Book from System Three -- you can download it free as a PDF file.

http://www.systemthree.com/

Check out the System Three Hall Of Shame, too. Very funny stories from System Three customer support.

http://www.systemthree.com/shame_index.asp

Cheers.

[Alan D. Hyde]

I've been in Wayne's shop, and even on a hot day it was IDEAL working temperature. No A/C was on, or (as far as I saw) even there. He'd simply done a great job insulating the shop when he built it.

Next one I build, I'm imitating Wayne. :cool:

You might pass along how you did it, Wayne. I suspect many others would like to know too.

Alan

[ 07-17-2002, 02:08 PM: Message edited by: Alan D. Hyde ]

[Bruce Hooke]

Regarding the catching on fire issue, I've had West System go off once or twice before I could get it spread out and it gave plenty of warning that things were not right by starting to smoke and get hot. When this happens it's too late to save the batch but it did give me time to get it outside and spread out to prevent a fire. The key is that I wouldn't leave a mixed batch in the mixing pot sitting unattended for more than 30-60 seconds, especially in hot weather.

As to where to get the stuff locally, you may find that it's cheaper to mail order, but by checking the West System website I can tell you that the following businesses are listed as distributors for West System epoxy in your area:

Boat US
18313 Egret Bay Blvd
tel: 713-333-9191
fax: 713-333-9203

Boat US
7280 Wynnwood
tel: 713-880-2160
fax: 713-880-1243

Boaters World
1003 Gessner Dr
713-461-9787

West Marine
7943 Katy Freeway
713-680-0707

West Marine
132 FM 1960 #E
281-821-2132

My local West Marine stores have a pretty good selection of West System products so they would be a good bet. I think West Marine also carries MAS epoxy but I'm not positive. There may be other local sources for West System epoxy as well that I didn't pick out on the West System website because I wouldn't recognize the names of nearby towns.

Rhode Island being the "Ocean State", and boats being VERY common here, I can even find West System epoxy at some local hardware stores! Houston is a seaport so if you look a bit you may find that it is fairly common down there as well.

If Lucas, TX is near you this place is supposed to carry MAS epoxy:

ALBERS WOODEN BOATS, LLC
1770 Northfork Lane, Lucas, Texas 75002
Tel: 214-547-0333
Email - Robert@alberswoodenboats.com
Website: www.alberswoodenboats.com (http://www.alberswoodenboats.com)

[John A. Campbell]

I use West System 105 resin and 205 hardener as a base coating on boat models prior to applying Epifanes varnish or George Kirby paint. . The result is a really good sealer that fills the Honduras mahogany grain very well and adds a lot of durability to the model BUT if you do this, you must first remove a substance called AMINE BLUSH from the cured epoxy surface before you apply varnish or paint. If you don't, the varnish or paint will not dry properly. The AMINE BLUSH is a pale yellow "haze" on the cured epoxy surface and is not always noticeable but you can be sure it's always there. I use a little soap detergent in hot water to clean it off followed by a cool water rinse and then let it dry overnight before varnishing. I buy my West epoxy products from Jamestown Distributors.

[capt jake]

Fire? I don't think epoxy by itself will spontaneously combust. Give off a whole hell of a lot of heat, yes! Just kep the pot away from other combustibles.
Please correct me if I am wrong on this.
The litle pots I have been using today got plenty warm (82 degrees outside). That told me, "use me!!! Or throw me out (carefully)".
smile.gif

[Charlie J]

Cedarhill- I've used WEST and MAS. There was a thread not long ago asking about MAS. I posted a comparison from my experience. Here's the thread address-
http://media5.hypernet.com/ubb/ultimatebb.php?ubb=get_topic;f=4;t=001129

Hope this answers your question

[Wayne Jeffers]

Originally posted by Alan D. Hyde:
I've been in Wayne's shop, and even on a hot day it was IDEAL working temperature. No A/C was on, or even (as far as I saw) even there. He'd simply done a great job insulating the shop when he built it.

Next one I build, I'm imitating Wayne. :cool:

You might pass along how you did it, Wayne. I suspect many others would like to know too.

AlanAlan,

Thanks for the kind words!

With the thought that perhaps someone may profit from my successes and shortcomings in building my shop, I'll post a separate thread when I have a chance. Perhaps at lunchtime.

Wayne

[warthog5]

My $.02. I have used 27gal now of 2to1 epoxy from Fiberglass Coatings Inc. I just got 6 more. I don't have the first complaint. I've used West. To expensive and will kick to fast for what I do with it.[Vacuum Bagging] Oh I do have 1 complaint. Due to the fact that I live in Fl. I have to pay shipping and TAX! You will not go wrong with this product. Here's some insite on it. I do not like pumps. They can screw up! The way I mix it is in graduated cups. I have the tops from auto supply pait store. The kind they mix paint on the machine. I use these to make nice easy pours of the correct volume in the cups. They have a spring loaded pour spout. If you buy the pail version. That's 15gal total. 10gal of resign and 5gal of hardner it works out to $33.00 a gal inc shipping

[almeyer]

Pull-doo,
I live just south of you in Dickinson. I used West System epoxy on my first-ever boat, and got it at Boater's World. Yes, it's expensive stuff - but it works. My first boat doesn't leak a bit, and doesn't have any mechanical fasteners in it. As for building, I waited until January to start, and will wait until January to start Boat #2. Even in the evening it's too hot to work in the garage during the summer time.
Al