Trimaran - Especially Searunner - Owners

[Mark Johnson]

Although they were not the first to use it, I believe it was the Gougeon Brothers That coined: "Wood Epoxy Saturation Technique". They did HUGE amounts of research, boatbuilding, and experimentation, (over decades) to perfect the technique, and their book: "The Gougeon Brothers On Boat Construction", would be the authority on how it is done.

"Saturation" is not really a good word here, as the wood is really just "coated". The difference with the WEST System, is that unlike Polyester resins or paint, water "vapor" can not readily pass through a good epoxy coating, thereby raising the woods moisture content. In wood, a high moisture content makes it heavier, much less stiff, weakens bonds, and in the presence of oxygen, can cause rot as well.

With WEST boats, they are epoxy coated inside and outside. Inside, it is best to coat the parts (before building the boat out of them), then just the seams, edges, and joints are left to be done from inside the boat. I have found that it is best to coat 3 or 4 coats, and then sand off two of these to level all wood grain & flaws. There will be pin holes, "holidays", and thin spots. Next, one coats 3 or 4 MORE coats, and sands off 1, to a TOTAL glaze, with NO shiny epoxy spots, ANYWHERE.

IF done this way, it will "end up" varying between 3 and 4 layers thick, and both the bonds between parts in construction, AND with future paint, will be assured. Only this multi coat & sand process, creates the desired 100% moisture barrier, AND 100% bonds. IT IS A LOT OF WORK! Various levels of "shortcuts" are frequently tried, with the subsequent various levels of maintenance hassles, over the decades that follow. Its a "pay now or pay later" situation...

On the exterior, the thickness of glass used in the matrix as reinforcement, will vary all over the boat, with he bows, radiuses, bottom (below the WL), seams, etc., getting several layers, the leading edges of fins & the keel getting 1/4" thick or more, and the rest being as little one thin layer.
This puts mere waterproofing where needed, and reinforced strength and impact resistance, where its needed.

IF done properly, with great care, and with the right glass schedule, these "Wood/Epoxy Composite" boats have an enviable strength to weight ratio, low maintenance, AND can stand far more "cycles" than all plastic composites, like FRP boats, (Even carbon reinforced)...

The "system" does not lend itself to mass production, sloppy work, OR going really fast & cheep. Slapping some epoxy on there, does NOT make it a WEST System boat. The best examples of these, are usually built by a rare, highly skilled individual builder, not a mass producer. It is generally not "cost effective" for them, but there are a few exceptions out there.

"COLD MOLDING" is a term whose accepted definition has changed over the years. A "cold molded" boat may or may not ALSO be built in the WEST System... (Was it coated inside, & glassed outside, with epoxy)???

As most folks would understand it, in looking at custom multihulled boats these days, a "cold molded" boat is built of "homemade" plywood, VS of many connected pieces of factory made plywood, as is the case with our Searunners.

On "molded" boats, there are numerous (6" or so wide strips), of VERY thin lumber or plywood, layed & fastened at a diagonal, over frames and stringers. Then, after a layer of thickened epoxy glue is smeared on this, ANOTHER thin layer of wood strips is applied & fastened over this first layer, at a diagonal to it. It is repeated 3 or 5 times... what ever the plans call for. You end up with a huge continuous piece of seamless, homemade, curved plywood! Unlike our sheet ply boats, these "molded ply" boats can be curved in both directions, creating more elegant & slightly more efficient shapes.

On Jim and John's "Constant Camber" boats, rather than being molded over the boat's frames & stringers... The molded ply panels are made before starting construction, over a separate mold, with the advantage of being much faster. They are vacuum bagged together while the glue sets up, creating more speed & fewer voids in the panels.

Next, these panels are stitched together, trued up, frames dropped in, and reinforced. CC lends itself well to long narrow multihull shapes, and was a huge development for the home builder, in speed & even money, especially if 2 or more builders share the mold!

Rather than getting much of its strength from the frame & stringers... the CC system gets its strength from having thicker skins, that ARE the strength, Because it has a minimum of stringers on the inside of the hull, this is a maintenance advantage, as the stringers are hard to paint... they also trap moisture and dust bunnies.

John Marple's, CC series, are very much like Searunners, but built in this system of construction.

IF built "properly", in the WEST system, all of the above can make good reliable boats, that will last a lifetime!

M.

PS... This 30 lb hard dodger frame, combines all of the above, with "foam & cardboard core" construction as well.

[Cavalier MK2]

The current edition of the Gougeon's book is available as a free download on the WEST website. It provides a detailed manual of their construction techniques including correct coating procedures. Other glues such as resorcinal were used first in cold molding techniques....

[Flight Risk]

Wow,
Thanks Mark very informative.

[Boatguy30]

Mark's quite correct on the pinhole info. I think the greatest threat to any wood epoxy composite are the pinholes. I prefer covering any below waterline, bilge areas with a quality epoxy primer like Interlux 2000. This; if applied with a short nap roller will fill most pinholes and highlight other that can be filled later much better than clear epoxy. This primer is of course applied over WEST epoxy sealed or glassed wood, but reduces the number of coats and steps (and weight!) required to get a totally watertight panel.

As an aside, a good ply and polyester glass (outside only) will last just as long as a WEST boat so far. I'm speaking of a boats built well with the inside ply not coated with anything other than perhaps a few thin coats of paint and kept dry. Lots of Pivers built this way in the 60s still around. Way more have been scrapped of course. Epoxy in some ways is almost worst than this type of build unless 100% perfect as the water and air gets in thru thin spots and pinholes/ cracks and can't get out. The boat I'm currently rebuilding had lots of rot between thick layers of epoxy and was launched in 1989.

Probably better to buy a Catalina 30 and call it a day!

Cheers,
Jeff

[Mark Johnson]

The multi step process that I recommend for coating with epoxy, can be down graded under "some" circumstances. One way, is use a really smooth clear wood, & a good exterior grade of (usually imported & metric) ply, with a SMOOTH outer veneer of Luan or Okoume. This reduces the first "leveling process" considerably. It is all a judgement call...

AVOID AMERICAN FIR PLYWOOD, or any other Fir plywood, even AA Royal Marine! This is where the multistep process must be maximized, to level the wood grain, and you will STILL get checks in it later, to a degree.

The "shape" of the piece makes a difference too. For example, if you make & scarf together ALL of your stringers, or frame edge lumber, (except the edge that will be planned down later), the inner three sides with a nice radius, NEED to have the multistep process, in order to assure that the inevitable "holidays & thin spots", from application flaws or sanding, do not coincide with one another. The same is true of pin holes!

Pin holes from the first coat, can be greatly reduced by working inside, out of the sun. They are from "out gassing" of the wood, during the epoxie's curing process. Tipping with a foam brush helps, but if left in the sun, it will out gas more. The best yet, albeit impractical, is to have a warm part, out in the Sun, then bring it inside & let it cool 5 min. NOW coat its first coat with the part continuing to cool.

I used to simulate this in my shop in the winter, by shutting OFF heaters, just before the first coat. The wood then IN gasses, sucking in the resin rather than out with the interior air.

The idea with the coat/sand process TWICE, is that the surfaces must be totally glazed over to assure future bonds, and if you don't do it this way, (two steps), one ends up with thin areas, or even almost dry areas, that allow water vapor to pass, OR get checks later. Painting or gluing together parts, inside or out, that have ANY shiny spots of UN glazed epoxy, is a mistake. There is NO chemical bond with cured epoxy. It needs the tooth!

Properly done... This process results in less weight, not more. Since the first process is sanded half way off, (depending on the necessity as stipulated), after you reapply & sand again, you mostly have a piece that is a CONSISTENT 3 layers thick. There may be 5% or even 10% of the surface that is 2 or 4 layers thick, but the "goal" is a consistent 3 layers, minimum.

Epoxy boats are lighter! A non W.E.S.T. boat will, over years, take on FAR more water vapor into the wood, (in weight), than the weight of the epoxy that prevents it. Also, as I said, DRY wood is stiffer = stronger, gets better bonds, and if built totally sealed, is immune to rot and usually, TERMITES too! Many boats up the Rio Dulce, for example, come out infested otherwise!

Epoxy is not a cure all! It must be done right to be the advantage that I suggest. Jeff's project, where he found rotted (but epoxy coated) wood, is an example. Someone must have slapped some epoxy on, (but not really sealed it), had water in the boat for years or decades, and this can result. Done properly, it will NOT happen!

The photo I include here, is a fairly recent flush through hull hole, that I drilled in our boat's 33 year old WEST system plywood. It is on the hull, down near the bottom, and always immersed. The glue, lams, & wood itself, are still perfect! Still... KEEP A DRY BILGE & STRINGER TOPS! This will go far with ANY type of construction.

If KEPT DRY INSIDE, good polyester boats, merely painted inside, will ALSO last a lifetime. These boats just have a stronger imperative to be kept dry, and over decades, may be a bit heavier & weaker from higher moisture content. They can still be fine boats, if well maintained, AND you avoid termites!

My 30 or so year old copy of Gougeon Brothers... Is the red vol #1. The book IS a good starting point, but one needs to understand the different requirements we have from theirs.

They are/were "in the boat building business", so must make a profit. Many if not most of my 1,000+ posts, are about techniques that I've developed that are sometimes NOT cost effective as a professional.
I only have a few, "well heeled" clients, that will pay me to "really go for it" in 100% mummifying these fabrications. Even then, I work for "time & materials", as it just "takes as long as it takes". The degree that one "backs off" of these processes, is up to the individual, under varying circumstances. They can still end up with a pretty damned good boat!

Also, Gougeon Bros build mostly... shorter lifespan, LIGHT WEIGHT, race boats, sailed mostly on the great lakes, with a very short (in the FRESH water) season. Many of their suggestions back then, like "merely coating exterior ply radii, and parts, WITH NO GLASS", will not stand the test of time... in hard, hot, tropical cruising, over decades.

I HAVE, however, "epoxied only" some pieces that were just too hard to glass, and done it successfully. These were hatch combings, breakwaters, etc. Still, I used the multistep process, 3 or more times, and got a PERFECT 6 or more coats in the end! This is a minimum for "epoxied only", on the exterior. On the exterior, GLASS EVERYTHING YOU CAN, Well! Not heavily, just 100%. It may take 15 or 20 years, but unglassed exterior parts, must be epoxied WELL or they will eventually fail.

Point being... Many of the stipulations in vol #1, did not stand the test of time (in our rugged cruising application), and after 30 years of building with the stuff, I have come up with pointers of my own. Not having read their newer editions, I really don't know if we disagree now or not? There is great potential there, with the W.E.S.T. System, IF done right!

Above all else, keep the bilge & stringer tops dry, and the exterior "well but not heavily" glassed, shaded by grey primer, and sealed!

M.

[Cavalier MK2]

The Gougeon's are now on version #5 of their book (blue cover) Boats such as Rogue Wave the 60' Newick tri they built for Phil Weld, have stood the test of time very well. Their methods have proven themselves . Attention to brushing in initial coats can eliminate air bubbles that can cause pin holes. Don't try to coat more at one time than you have the patience to do right.

Marine Fir ply can be an excellent material. My suggestion is to use it where a smooth interior finish is not needed such as wings and amas, or in double diagonal/ laminated/ CC etc. construction. Meranti if you can find it is a similar weight and strength to Douglas Fir but with much nicer grain for a level finish. Hand sanding can take the glaze off low spots without going overboard with the sander and expense of a quadrillion coats of epoxy. That said if you have the time and wallet you won't hurt anything going for a level finish. At all costs avoid any Fir ply that is less than marine grade. Hemlock is being used in lesser plywoods now and has less strength and poor rot resistance.

On the epoxy coated tri with rot I'm wondering if water got in through a unsealed hole. Every fitting hole for bolt or screw should be sealed with epoxy. Then if your chainplate or A-arm drips it is just a leak, not the start of rot. This is one of the first chores I would recommend for an boat owner, even new builds often haven't taken the time to do this.

[Mark Johnson]

As I said, my couple of small "issues" with the Gougeons' writing, was as it was written 30 years ago. (I haven't read their later books,)... I don't even agree with MY OWN articles that were published that far back. We have all learned a lot since then. Their orientation back then, was as I described, toward FAST, light weight, fresh water, racing boats, sailed in a short season, AND ice boats... NOT year round, heavy duty, salt water, tropical cruiser, full time liveaboards, like our Searunners.

Of coarse ALL small or large holes & openings in the ply needs numerous coating & sanding steps, so that IF the caulk fails, it is merely an inconvenience. (I use a small chainsaw file for sanding the rough interior smooth, between steps, btw).

ANY Fir ply is a terrible choice, to be used "with the WEST system", for the reasons given, (too much grain & hard/soft striations), and this applies to "AA marine" as well. IF it is "not" WEST system, and one goes with Fir anyway, it had better be "marine". IF it "is" WEST system, and one goes with Fir, then one can use standard American exterior ply, but it is still not advisable. Our boat is mostly made of 33 year old, (but well WEST Systemed), exterior ply, and in GREAT shape. (Not a speck of rot on her). Using the WEST system, the reason to avoid "standard American exterior ply" anyway, is primarily that the voids cause inconvenience in construction. I filled all of mine, and it took a LONG time. I already explained why Fir is a bad choice of species.

For use with the West system, smooth veneer, imported ply is best, as it uses far less resin, requiring far less sanding. Their "exterior ply" IS marine grade. (It is not like how the US grades, in 3 categories). Imported "exterior" Okoume, is far better than US exterior grade construction ply. Smooth, tight grained lumber, also coats & sands easier, lighter, and with fewer steps. Not that this makes an inherently better boat, IF both are WEST System, just a bit faster to build, less expensive in the end, and probably lighter too.

Cavalier is mostly incorrect, or "inappropriate" as usual. His comments generally are less than "useful", and he seems to enjoy contradicting everything that I have said, ever since he joined in this "Searunner" thread, even though he doesn't have one. He doesn't know what he's talking about! Cavalier seems more interested in arguing... being smarter, righter, more experienced, etc. and picking apart others comments, rather than listen & learn.

You can think that a polyester glassed, non WEST system, Fir ply, work-boat finished Searunner... bastardized with a keel rather than a board, and covered with Latex house paint, is what YOU want. That's fine for you, and certainly an alternative way to go. To suggest that OTHERS follow you down that road, and it is actually a "better boat", is unconscionable, in my view. Why don't you just do it "quietly".

To the best of my ability... I have been putting out a lot of useful information, for the sole purpose of helping out my fellow Searunners. I don't do Facebook, Tweet, or even Text. "I don't need to be social on the internet", OR engage further in what Cavalier has reduced into a pissing contest...

Cavalier, let us all know when you're done...
M.

[Cavalier MK2]

Ah yes Mark, You've reminded me not to get in a p*ssing contest with a skunk...As usual you've deliberately misconstrued what I posted. I build with the WEST system and have read the latest instructions. Reading the book 30 years ago doesn't make you more qualified than the people who wrote it, did the research and keep updateing it. There is more than one way to skin a cat or plank a tri. I'm glad your methods work for you but I doubt all Searunner owners have your mind set, prejudices or misconceptions. BTW Technically I do own a Searunner.

[Boatguy30]

Hey, good thing you guys live so far apart!

[Cavalier MK2]

He's been in the sun too long.....

[trisailer]

I cut my a-frames and am now working on a folding system.
Have one amas in folded position and everything so far matches up.
Looks like I will end up 11ft wide with the folding system, but again no biggy as permits are easy to get and cheap.
Well worth the hassle to have such a nice boat fold up.
Have attached a couple of pictures of her folded on the port side.
I will launch her folded and let the water bouncy float the amas into the up position.
Very similar to Farrier design.
Also will be adding extra internal tubes in the Amass, to strengthen them.
N





ow to find someone to fabricate the needed hinges and bolt plates for the top tubes of the amas.
Wish me luck.

Originally Posted by trisailer

Well I did it.
I trailered my Searunner 31, 2400 miles.
Bought her in Napa, California and trailered her to Wisconsin.
Demounted the amas, tucked them under main hull and away I went.
Built the trailer from an old house trailer frame and axles.
Even used the old house trailer tires, which were around 30 years old.
My wife had never seen the boat, so when I got home her reply was "Holly **** that is a big boat"
More details to follow, if interested.

[Cavalier MK2]

What about a line or lines attached to the outboard ama sheer and run through a block to a winch on the cabin top? You might need a tackle to get enough power. That would allow you to secure the amas before you enter the water and raise the mast. You probably would have to start them swinging up anyway, a searunner is apt to roll while attempting to deploy, you wouldn't want the mast on deck etc.... As you know a Farrier has the amas folded much higher where they can stabilize the boat when it is at its immersed waterline.

[Cavalier MK2]

For safeties sake I should mention the obvious like make sure the winch and block are well backed and up to the load. Another idea is to use a short gin pole stayed in the mast location to get a better angle to lift from. Also don't try to raise the mast on land if the trailer stability isn't up to it etc...Hopefully you did the engineering and fabrication of the swing arms right etc....

[rossad]

There are several Searunner Owners looking at these last few pages seeing the cat fight taking place regrettably on such a great thread. It is important to keep this thread alive and give just the value of what you trying to achieve regarding the technological aspects to boat repair building and systems. There is so much to learn with these Searunners and a life time isnt long enough to get it as perfect as one would like. Objections to others is best left out and the readers will easily see what is their better options for themselves......

[Cavalier MK2]

trisailor, when are you planning to hook up the fore and aft wing beams, the ones in the leading and trailing edge position of the wing deck boats? Without any fore and aft movement braces your vertical swing arms will be very vulnerable if you launch as described. Setting up on land would allow you to fasten those in position before launching.