Epoxy substitutes

Post your own building tips and "how to" ideas here.
Post Reply
jem
Site Admin
Posts: 4915
Joined: Fri Jun 18, 2004 8:14 pm
Type of boat I like: Wooden
Location: Greensboro, NC
Contact:

Epoxy substitutes

Post by jem »

Many builders don't care fore the cost of epoxy and I can't say that I blame them. Stuff is not cheap.

Many search for cheap alternatives. Polyester resin is often selected as one of them.

Epoxyworks (West Systems' newsletter) did a study about effectiveness of different coatings at keeping moisture out of a dried piece of plywood. The study had some interesting results.

http://www.epoxyworks.com/25/pdf/Moisture_Exclusion.pdf

I'm not sure how long the article will be there so I'll summarize. In order below, with 1 being the best and 7 being the worst, these coatings rank as follows:

1) West System 105/205
2) Vinyl Ester
3) Low Performance epoxy systems.
4) 2-part polyurethane paint
5) Polyester resin
6) High-solvent epoxy penetrating systems
7) Formaldehyde

Now this is a West System company study so I'm sure they are not telling what they consider a "low performance epoxy system" to be. But my gut tells me it is any epoxy system with high mix ratio of like 4:1 or 5:1.

What I found most interesting was that 2-part polyurethane paint holds out moisture better than polyester resin!

Now we must take this study with a grain of salt. For paddle craft that don't stay constantly in the water, the importance of moisture exclusion decreases a bit.

But bottom line: for the best protection, you can't beat epoxy.
-Matt. Designer.
hairymick
Design Reviewer
Posts: 1965
Joined: Wed Jan 04, 2006 8:54 am
Type of boat I like: <-- Please read instructions to the left and delete this text. Then, tell us what type boat you like! :-)
Location: Queensland, Australia
Contact:

Post by hairymick »

G'day Matt,

As you know, I am a West Systems user now and swear by it. I have found that these people are passionate about their product and the people from West who I deal with here in Australia really do care about you achieving your goals in build quality and finish.

They have been a gold mine of information to me.

I would recommend using the 105 resin, coupled with 207 special purpose hardeners. This is what I use and I just can't see myself changinging to anything else, anytime soon. The stuff brings up allmost a mirror like finish with absolutely no ammine blush and is a pleasure to work with while wetting out. (but then again, I am an epoxy junky) :P

The other stuff they mention in their review may well work OK but to be perfectly frank, I don't care if the work or not. I put way too much effort into my boat builds to compromise them with an inferior product.
Regards,
Mick

JEMWATERCRAFT Swampgirl; Wadefish;Touring Pirogue;South Wind; P5 ;
Laker X 2, Sasquatch 16.5 T-V 15 Okwata 15:
Cobia 15 (under construction)
Kayak Jack
Design Reviewer
Posts: 1186
Joined: Sun Jun 20, 2004 8:03 pm
Type of boat I like: <-- Please read instructions to the left and delete this text. Then, tell us what type boat you like! :-)
Location: South-central Michigan

Post by Kayak Jack »

Mick,

I've used System 3 with good results too, but will not argue with either West materials or results. You feel as passionately about epoxy as I do about plywood. 4mm Okoume builds good boats - period.

Good materials won't guarantee a good end product, but poor materials can sure as heck guarantee a poor end product. The only chance I have is to use the best materials. My workmanship sucks, and needs all the help it can get.
Kayak Jack
Doing what you like is FREEDOM
Liking what you do is HAPPINESS
I spent most of my money on whiskey and women - and I'm afraid I just wasted the rest.
hairymick
Design Reviewer
Posts: 1965
Joined: Wed Jan 04, 2006 8:54 am
Type of boat I like: <-- Please read instructions to the left and delete this text. Then, tell us what type boat you like! :-)
Location: Queensland, Australia
Contact:

Post by hairymick »

G'day Jack,

Mate, I don't have access to many of the materials you do. There may well be superior epoxies to West but I haven't found them yet.

I would like to try some of the Raka stuff Matt recommends but don't have access to it.

None of the so - called premium epoxies that I have tried out here come anywhere close to measuring up to West.

With the service ATL composites provide, coupled with technical expertise and exceptional customer relations, I just can't go past them.
Regards,
Mick

JEMWATERCRAFT Swampgirl; Wadefish;Touring Pirogue;South Wind; P5 ;
Laker X 2, Sasquatch 16.5 T-V 15 Okwata 15:
Cobia 15 (under construction)
Kayak Jack
Design Reviewer
Posts: 1186
Joined: Sun Jun 20, 2004 8:03 pm
Type of boat I like: <-- Please read instructions to the left and delete this text. Then, tell us what type boat you like! :-)
Location: South-central Michigan

Post by Kayak Jack »

I think West Systems are top notch materials. Stay right where you are. I just happen to agree with you about good materials. I do NOT want to go out away from shore in deep water in a boat made of the cheapest stuff I could find.

That's sort of like a guy working on tall buildings while wearing the cheapest safety belt he could find. A set-up for a Darwin Award.
Kayak Jack
Doing what you like is FREEDOM
Liking what you do is HAPPINESS
I spent most of my money on whiskey and women - and I'm afraid I just wasted the rest.
Post Reply