Insulating the hull questions.

[Tony G]

You gotta figure a thousand minds are better than one half. So who has read or experienced what, thought or been told or has it on 'good authority' as to the prefered technique when it comes to insulating the hull?

Peviously I read insulate everything from the overhead to the cabin sole. Then someone stated that below the waterline insulation would trap condensation making an ideal environment for mold growth. The counter argument suggests that you want 'insulation' from the temperature of the water,be it warm or cold. Then some say, no, it's the heat of the sun we need insulation from. Then somewhere along the way it was postulated that panels of insulation may actually provide cover for insects and cockroaches!

I recall Tim L. using rigid foil backed insulation in the salon on Glissando and, what I thought was genious, carpet runners in her lockers below the waterline. The little gripper spikes held the plastic off of the hull thereby allowing any condensate to trickle to the bottom of the locker and out a weephole. But what if you've made theoretical water tight lockers?

I really don't like the idea of gluing anything to the hull-'don't know why but something from the back of my mind says don't do it. I really only gave consideration to insulating behind the ash ceiling strips. Which, now that I think about it is about as sound as insulating your house but leaving the windows and doors open (reference first sentance of post now).

Who has the goods? What route have others here taken? What works, what doesn't? Once we get this mundane rigamaroe out of the way we can move on to more pressing topics like wine racks!!

[Westgate]

Tony:

There is a good thread on the Plastic Classic site on this topic. Many different techniques/ideas are presented. Perhaps you have already visited but figured it was worth a mention.

Andrew

[ebb]

Have some 1/2" sheet pieces of very light white foam loose in the back of the truck. I knelt on it, put tool boxes on it, stuffed it around things that needed to be imobilized. Tough material. Been there for a year or more - I mean it has some permanent dents - but I won't bet on it. It's amazing stuff. You see it used for packing.
It's called Ethafoam. It was real cheap when I bought it at TAP Plastics. It is bendy and pliable, cuts with knife or scissors. It's CLOSED CELL polyethylene foam. It would be perfect insulation if you could find something to stick to the hull with!
One of its great qualities is that nothing sticks to it!

Another material worth looking into is Tekfoil (and other brands) which is various layers of bubblewrap and foil and sometimes polyethylene. The foil is coated when it's an outer layer. There are seam tapes and double sided tapes to stick it. I'd experiment with carpet tape.
Again no mastics I'm aware of. But I've heard some people are putting it into boats. To keep condensation at bay imco you have to have to glue whatever insulation tight to the hull without holidays. Dunknow?

Years ago I got a deal on some 1/2" Ensolite - it's a tough, light tan colored, closed cell pvc rubber.
Hours of research to find a non-lethal mastic led me to a waterborne gel/paste called APAC 564. It's a 'green' flooring adhesive for all kinds of vinyl flooring products. Have glued some 'panels' onto the hull in one cockpit locker.
The job was a PITA because I did it after I closed it in - like an idiot. But they're stuck and seem ONE with the hull.

There must be some mastic that will glue polyethylene - maybe APAC has it.
You may think that this is the Age of Aquarius BUT it really is the Age Of Glue.
Thing is if you got hot summers or you're going tropics, the fiberglass is going to get really hot. The stickum has to hold through what?... a 150 degree range?

I also found some nice beige 1/4" cut-pile polyethylene auto 'head-liner' material. Not really insulation. Actually the doors & footwell in my truck is covered with similar stuff. (Polypropylene pile is commonly used for auto and boat liners - imco we want material that doesn't hold water. Water FALLS out of my polar-fleece jackets, made from recycled p.ethylene 7-Up bottles. The auto liner is the same stuff.
(Head-liner in the Dodge is a thin fabric not glued very well to friable foam.)
'Carpet liner' has an amalgamated backing allows it to be cemented onto boat surfaces. Intend to glue it onto the Ensolite in storage areas. In other lockers, imagine cutting hull carpets to fit, but hanging them in with velcro hook & loop, so they can be removed and washed. They'll have insulating and cushioning value in difficult access areas.

Consensus has it, we should insulate the hull above the waterline where rapid changes in temp and humidity causes condensation. So I'll be attempting this. Another good reason is that, as with any insulation, we're warmer in the winter and cooler in the summer. Thinking Hawaii!


May have got the cement thing covered with the acrylic pudding APAC564.
But what do I know about the outgassing of super-heated pvc foam. Pvc does NOT have a good rep. MSDS sheets exist to reveal info that's hidden by 'trade secret' clauses. They've got carcinogentic plastisizers and other ingredients that makes PVC NON-recyclable. Plastic bad boy that has contaminated the oceans and toxified landfills everywhere on the planet.
All clear plastic films are also implicated in toxic horror stories.
So lining the interior of the boat with this stuff is something to be real about.

[Tim D.]

Ebb, I have used a waterproof contact cement like "Barge" for years on closed cell ensolite material to outfit kayaks and canoes. It seems to work fine, I am assuming that either this is not what you are looking for or you find its flammability unacceptable.

[epiphany]

Tony et al -

I have found thru experimentation that Gorilla Glue (and likely its similarly-chemical cousins) can be made into a sort of an 'expanding glue'. You just have to mix it with a lot of water (and fast, and apply it fast - pot life is like maybe 10 minutes).

I will be bonding sheet foam (EPS - pink or blue) to the hull using this. Besides a very strong bond, I think the 'foaming' property will cut down on the "holidays" Ebb mentions. Condensation forms from atmospheric water (humidity), so if you can seal off a small area, you shouldn't have that as a problem. I'll be adding a layer of luan/doorskin ply to the outside (the cabin-side) of the foam, and a layer of 10oz glass over that to protect it and make a durable, easily-cleaned surface. Because the EPS foam will be behind wood, I will be able to use cheaper polyester resin instead of epoxy when glassing over it (People may poo-poo polyester it seems, but the stuff has held the boat together fine for the last 40 years, so I have no problems using it where I can!).

I'd like to sneak in a radiant barrier right up against the hull if I can. A layer of mylar 'space blanket' material would work great, or maybe aluminum foil. Have to play with that a bit yet, make up some test pieces, see if the GG can bond to either of those materials, or if I'll need to perforate it...

I'll be putting insulation (AKA 'flotation' ) against every bit of hull I can, above and below waterline. Condensation forms all over, everywhere - I have seen it often in the past 4 years of living aboard. It is a bit more prevalent below the waterline, when conditions are right - but that is not always. I also want to treat the overhead in the v-berth, somehow...

I like the GG because I think once it is cured, it will not 'outgas' much, if at all, and seems to be a really stable substance. The other material I considered was something like 4200/5200, but the GG can do the same job for much less money and mess. I want whatever it is to be pretty much permanent - it would suck to have your hull insulation/liner delaminate after a few years, and my experiments with other glues like contact cement, Goops, acrylics, and such showed me that you need to make sure it is a really good bond, when going up against the hull. Most of these failed to some degree. GG becomes an inert solid after it has set up, whereas the rubbery adhesives are always slowly degrading (outgassing) to some degree - losing some of the very stuff that makes them what they are. How long until that has an adverse effect on the job they are doing? Your guess is as good as mine. So I am opting for a glue which does not have that propensity.

I like the idea of solidly encapsulating a solid foam (as opposed to gluing in a pliable foam) because it seems that would hold the materials in stasis better, for longer. If balsa can stay as dry as it does in the deck for 40 years (assuming no water penetration), so that it looks like it was installed yesterday when brought into the light, it just seems to me that encapsulation is the way to go.

[ebb]

Kurt, we have talked about your pink foam idea befor, so excuse me please if I repeat stuff. Pink and blue foams are relatively stiff sheet POLYSTYRENE FOAM insulation usually found at the big box depots.
Small panels could be heated and softened and pushed into the compound curves of an A/C hull. The compound curves are essentially minor in small sections. Gorilla polyurethane glue though is fairly expensive. But probably a good choice considering hull heat and cold cycling.
I think the pink foam is gluable with anumber of mastics - I wonder if tube 'threshold cement' could be used? Or perhaps tube glazing caulks/sealants (not silicone) that are formulated more toward heat extremes than construction goops.
[later EDIT: one structural polyether tube goop, I can recommend, is Chemlink M-1, considered green, non-toxic, bonds almost everything.
But haven't used it for the purpose here myself. There may be a problem getting it to set if no air moisture can get to the glue under closed cell stuff. It may not matter becauwse it begins setting immediately. So after tooling it on both surfaces with a toothed plaastic spreader, the open time may have been enough of a catalyst to promote it becoming rubber. More elastic formula Chemlink Novolac might be better for this app.]

I agree that polystyrene should be encapsulated.
As you say to protect the boat's interior from the foam's outgassing when the hull is heated by the sun or the ship's stove.
The encapsulation might also be augmented with paints. A good one imco would be a waterborne rubber urethane. As in deck paint without the antiskid.
Or an acrylic latex exterior house paint.
The encapsulation is suspect too, even plywood has formaldhyde in the glue.
SO encapsulate with glass or ceramic!!

Polyethylene foams don't have the same outgassing problems that the Bisphenol A toxin group has.
Note that when this foam burns it doesn't produce lethal smoke - which can't be said for other foams.
Who knows for sure? To be safe ALL foam insulation in the enclosed interior of a boat should be encapsulated.
Ensolite is used for a host of consumer products, everything from kneepads to yoga mats, and Airex is the same stuff in expensive closed cell mattress form. Bad chemicals. Goodlord maybe warmed up gelcoat and epoxy paint will compromise my tired immune system.

Tim,
I'm old enough to believe that that most of my body's complaints is due to decades of direct exposure to chemicals/solvents I've used. I think most of my toxic episodes are cumulative. Once thought the liver and kidneys where born-again and repairable.
NOW I go nuts trying to find less lethal materials to use on the boat,
especially inside.
Can't work with a canister mask on - besides having a beard which screws up a mask's breathing seal.
That non-toxic floor adhesive is not bad stuff - altho finding it was a problem.
Waterborne glue takes longer to set up than solvent glues - especially when you're gluing on closed cell material! Might ask if it ever sets up in some places? You have to be able to hold it in place by putting props or pressure on the panels.

California has led the way in safer products. You can legislate the great corporate planet polluters into making more friendly products.
But never turn your back on those jerks. Remember WCField's first law of consumerism:
"Never give a sucker an even break - or smarten up a chump."

[ebb]

Hey Kent,
Glad you're still here!
Finally got back to the boat and happen to be gluing
vinyl coated polyester fabric onto the ensolite I pasted into the boat just about everywhere above the waterline years ago.
I think Armacell is a new owner of the name ensolite and is trying to obsolete the old with formula changes probably and name recognition. Ensolite has been around forever.

The ensolite I have is light tan and has a wrinkled 'skin' like surface on one side* - not really skin but more like the smooth mold surface it was extruded out of. That's the exposed side I'm covering. Imco it's not a good surface to keep clean, even tho the closecell sponge won't absorb liquids. The opposite side cut surface has a definite cut cell texture.
Like the light color. Notice in the Armacell lit a lot of their ensolite foam is black. Ensolite has a soft feel even tho it is firm. Tho firm, it's formable against the concave curve of the hull. Light color allows pencil marks and notes to be written on it. Don't think I'd be happy working with black stuff.
* the surface cosmetic may have been the reason I got a good deal on a good quantity.

APAC 564 paste advesive
The waterborne acrylic mastic I found is essentially as odorless as the ensolite. Probably find pastes like it now available at bigbox.
Working and sweating inside the boat without solvents and sweet lethal ordors is a pleasure really. [The adhesive is APAC564 - it has some special attributes. Company makes a family of stickums. Remember talking with a saleman who, after explaining my intended boat use, recommended 564.
After 'troweling' both surfaces, you let it sit for a short time (minutes, depending on temp and humidity) and the piece you are putting on will grab immediately. With varying degrees of dry/wet you can reposition the piece if it is still wet enough. That's one thing that makes this adhesive useful. Another is what they call 'resiliant'. Have used the adhesive as an impromptu filler. When set the exposed adhesive acts like 'resiliant' rubber.
Excellent 'sheer, peel, green & bond strength - anti-microbial, solvent free, 5cycle freeze/thaw stable.' Comes in a 4gal bucket. google the tech data sheet. Recommend it for ensolite. Got it through a flooring contractor.] Acquire some 3" - 4" small V-tooth PLASTIC spreaders. RedDevil - Hyde.
Adhesive is a non-immersion product. Imco if you leave no cracks, openings or voids for water to condense or sit in, this stuff works fine! IMCO !

So the vinyl is from McMasterCarr (pg3508). 5' wide, $5 a foot, .027" thick. Maybe not standard drygoods - it's 'sun, water, mildew & tear resistant' and white. You can see the sheet has a grid, and it has a shiny side and matt side. I've put the matt side out, but dirt likes it. And maybe mould too, but being vinyl should clean up by wiping with detergent. Check out exterior vinyls at SeattleFabrics.com/

I also have some nice tan polyethylene (NOT polypropylene) automobile liner material that I was/am going to use. It's the 1/4" thick hairy stuff you used to see on seat and door panels. Even tho water falls out of it, not so sure I'll use much of it to cover the sponge. But it's nicer to lean against, put a bare arm or foot on, much nicer than clammy vinyl (or bare ensolite) where you bunk.

So I'm covering the rubber insulation. Which of course is not absolutely necessary.
It does keep me from splashing the boat and going sailing.

The white acrylic paste is very sticky stuff. But not viscous like rubber cement. It does produce an absolute bond if you slather it on (with a 1/16" toothed plastic spatula) both surfaces - leave them open for a short period. Since it's not contact cement, you do have a small positioning window applying the ensolite against the hull or the floppy vinyl sheet on the ensolite. However you need faith if you paste on wet that the wonderful water resistance of both materials will allow enough water vapor to escape to produce bond. You need to fool around with the materials.
The peel&stick version of ensolite sounds convenient - BUT you get NO repositioning grace. Once it grabs, that's it! Stckum on one surface only.

The ensolite I'm using is firm enough to actually block sand rounded corners, etc on the edges to get a really tight void free fit against the hull.
As for longevity, the foam is found in gyms and outside at pools. It's your traditional camping and yoga mat. Lit avoids mentioning UV or weatherability. But I looped a narrow strip of ensolite around an outdoor sawhorse that lasted at least two years exposed. Disappeared during a clean-up frenzy. It lightened up in color, stay bendy and didn't crack or shrink like you might expect.

Have fun

[Hull376]

Thanks, ebb. You can still get Ensolite in the tan as far as I can tell from Armacell's website. As luck would have it, we have a local distributor for most of their product line here in Houston, so I plan to to show up and have them show me what they've got. I'm going to grill them about benefits of Ensolite versus some of the other elastomeric foams, such as Armaflex. I tend to agree that light color would be better than black, unless you already have your head around either painting the surface or applying a vinyl fabric. BTW, let us know how the vinyl covering holds up or if you'd do something else if you could rewind tne tape! I've decided that if I do this insulation job, I want to do it right the first time, even if it costs a bit more. I'm trying to get rid of mold and condensation on the hull, and so many of the other solutions may work for awhile, but then fail after a few years and make a real mess. I like your comment about adhesives being tne current "it" product. Staying stuck to the hull is probably the biggest failure risk with these elastomeric foam products. I have visions of a one inch thick sheet detaching from above the V berth, while it may be just fine on more vertical surfaces. Maybe 1/2" on the underside of horizontal surfaces. Something I haven't seen any posts on is injecting pu foam between the coach roof and the inside liner. Doesn't mean it hasn't been discussed already, I just never saw them. Guess I could do a search!

[ebb]

Kent,
Injecting 2-part urethane foam between cabin and liner would be a problem because the pressure created by uncontrolled foam expansion will make your liner bulge like a pregnant dog. Don't believe the process chemicals have changed: reaction gasses are toxic, and because the cells are not truly closed cell the gases can continue to leach out... for (not knowing the stats...) for your forseeable future.
There are single part aerosol construction foams that advertise CONTROLLED EXPANSION - that might actually work. HOWEVER, you cannot prep the inside surfaces of the liner or cabin. Imco when they were made the last coat of polyester had wax added to get it to set hard. Foam that is not sticking in non-accessible places will hold moisture, get smelly & go bad. Don't inject urethane into your boat ! ! !
I believe just about any foam urethane is toxic, it never becomes inert.

Empty air space is a pretty good insulator.
Wonder how much condensation you notice on the cabin liner overhead when your boat is dew-pointing vapor ladened air and the windows are dripping. The top of the coach roof is balsa composite. Where the balsa stops must be before it makes the difficult transition at the corner curve to become plain fiberglass sides. The liner creates a hollow space which may also keep condensation from forming on the cabin sides in the cabin - but condesation may form inside in the damp space between the liner and the coach sides.

Impossible to seal cabin side windows (dead lights).
The strange original Pearson squeeze frame mounting system and floating lenses of the large windows use the bendy unfilled space between the LINER and the PLAIN 1/4" thick sides to make the ineffectual seal of the window frames possible at all. And as everybody knows, the windows are leak prone because of this poor design. It will be impossible to fill the vertical sides of the cabin with 2-part polyurethane foam, you'd have to create difficult jigs to keep the sides from blowing out the liner inside. There is no 'FLAT' to the existing liner. Even outside will billow out in places imco. In use polyurethane foam will disintegrate if it moves at all. There will also be voids & adhesion issues.
Actual partial filling in between liner and cabin sides with epoxy for alternate window systems has threads in this forum.
__________________________________________________ __________________________________________________ _____________

The PVC/foam rubber product is a good candidate for that white paste. Very gluable. There are bigbox products available that will do better than regular contact cement. Better then water based contact cement alternative. What's likable about paste* is that you control thickness with the toothing of the applicator, means you can have less voids between the surfaces (that you will get using thin film high solvent contact cenent).
Have used the acrylic paste to fill seams around the foam cakes - making seamless embedded insulation. You don't have to do that, but no water will seep in and algeanate, no dirt, no little creature hotels. The thicker paste 'filler' eventually dries into a firm flexible rubber, and seems to be completely bonded with foam and various surrounding materials.

Haven't done it myself (we grinded down to green polyester) but if you dewax, clean, abrade and smooth the old painted surface, I'm sure the acrylic paste will stick - better than the old paint you are covering, most of which is bloody bonded to the hull.

Imco you can paint ensolite with flexible rubber urethane deck paint (without the anti-skid in it.) after it's installed.**
Haven't done it specifically. Prefer the smoother shielding surface of vinyl fabric. Which also gets totally bonded to the foam.

I have moral and chemical problems with PEEVEECEE. A UNIVERSALLY BAD PLASTIC. Think it is an unethical irresponsible plastic that in various forms is killing all creatures great and small on the planet. The ensolite I have is so old that its real danger may be its old age. My problem too. The vinyl I just got is low odor, maybe it passed its gasses into the MMC warehouse environment while waiting for my order.
Can't think of any any insulation products that are inert. Maybe balsa, the great insulator - but it rots. There are no CLOSED CELLS in nature...
__________________________________________________ __________________________________________________ ________
*Bostik makes a pleasant smelling, non-toxic, water based acrylic, smooth white paste for cork and carpet tile called InstantPro. The TDS makes it sound similar to the stuff i'm using. Remember I'm also using the 564 as an 'experimental' fillit - with a finger and extra paste radiusing the bottom of an ensolite panel where it butts the settee - to create a mopable waterdam of sorts.**
Open time (very important) discussed in the data sounds like my stuff. "Inside only" - may refer to constant water wet-softening the set glue. Might not use it in the cockpit! I'd worry about inside boat use if the closed cell foam allowed water in! Tend to trust Bostik products. (so far)
__________________________________________________ __________________________________________________ _________
**Have painted white water-based urethane rubber UltraTuff nonskid deckpaint (without granules) into lockers befor they become inaccessable to further painting.. Assume the stuff bonds to any exposed acrylic paste where ensolite was installed - sealing plywood and seams from standing moisture. Also rubber surface might add some traction for objects in the locker that hard stuff can't. Exposed to view, it's a lousey look, imco.

[Hull376]

Ebb,

I very much appreciate your input on this. You know, now that I think about it, it takes a lot longer for any mold to appear on the liner, as you state. So the air, balsa, or whatever the Portuguese builders did with 376 does provide some insulation to reduce instances of reaching the dew point compared with the sides of the hull. I won't fool with it! You've given me ideas on attachment and surface coverings. Most importantly, you've confirmed for me that I'm not crazy to be thinking about using elastomeric foam sheets, PVC or other compound ( my visit to Armacell distributor may help me there) versus other alternatives.

[ebb]

Kent,
There are other fun foam sheet plastics, one of which is Ethafoam.
It is a translucent closedcell bendy polyethylene. BUT we can't glue this more friendly foam to the hull.
Possibly there's a glue by now that we haven't heard about yet. It's way cheaper than ensolite. Used as packing material for shipping.
Requirement may be that the surface of the sheet be pretreated with a propane torch to change its 'surface energy'
and then stuck on with a nice acrylic 'yogurt' paste. Haven't tried this myself !

Armacell also produces wax plastic (polyethylene p.olefin) insulations. They may have a waterborne mastic that sticks it.
NO aromatic solvents, OK? !

Ask the Armacell tech about gluing in the foam insulation he recommends
if it's not an ensolite.
The CLOSED CELL insulation must be firmly attached to the hull. Bonded.
Once it is embedded and bonded, no condensation will form and a good waterborne paste won't be a problem. If it's not continually immersed.
Ensolite in most ways is ideal because it conforms to mild concave surfaces. When gluing in, pushing it against the hull will keep it there.
This means the sheet won't tend to pull back into its flat sheet form (OR create a bulge) when gluing to the hull.... like other less docile foam materials. It's what makes ensolite the only closedcell foam that is also comfortable for expensive flotation cushions and bunk pads.

Also want the glue to bond to the rubber. It's possible that even regular contact cement can be pulled off the foam. Observed this once, it's not something I would swear to.
White carpet layer's paste is something to look into to. Acrylic glues are a minor miracle of sorts. See post #10, APAC 564.
(Defender & others have a liquid waterproof capet adhesive - not described as a paste - tech data sheets seem unavailable at any source. The origin of the carpet adhesive is Redrum Fabrics (makers of Nautilex marine fabric glue). Billed as non-hazardous. It works by
water evaporation in application, like 564, and other waterborne pastes. Forum user complains of material not holding on vertical surface.
Defender - Marine Carpet Adhesive - (Redrum Fabrics)Maple Leaf K-Grip 398, $34.99gal. Waterproof after cure. Is this roller or trowel???

[ I have the acrylic paste and the ethafoam, maybe I should do a test??? ]


You might be persuaded to use tube polyether or polysulfide. (Imco these structural adhesives, including tube urethane are WAY overkill) you'll still have to spred the material with a toothed spatula same as the yummy waterborne stuff - to get total no void coverage - and on both surfaces! Cost hundreds of dollars, and the cruds are viscous and messy to use.
There are no marine tube synthetic rubber caulks that will glue HDPE, polyethylene foam.
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[ Be warned and do your own confirming/testing. So far as I know this method is not supported by public forum. Nor Nigel, Larry, Maine or Don. Nor PracticalSailor or GoodOleBoat.
Personal research and luck (good & bad) led to the method, which seems logical.
And the inside of litlgull seems sucessfully insulated - from sheer to more-or-less waterline - with ensolite and a fine non-toxic cork&carpet paste.
This is.... in my considered opinion. ]

[Hull376]

Ebb,

I got my sheets of Armacell Armaflex after visiting with their distributor in Houston. They said it is the best foam they have for enclosed areas and is used in school HVAC systems. I got 1/2" 36x48" sheets. I also sourced some white vinyl cloth and glued it to one side of each sheet. I tested cutting the sheet with the vinyl using scissors, regular knife, hacksaw blade, box cutter, and electric carving knife. The carving knife was way way superior to the others. Cut like butta! I made patterns with brown paper, and transferred to the sheets. Cutting them with the electric knife was soooooooo easy. Very clean edges, no tearing. I looked at the adhesives, and I decided to take a chance with the 564 enviromentaly friendly adhesive you used. No way do I want to use volatile death chemicals in the cabin. Also, the ability to slightly move the pieces during installation is a selling point versus contact cements. I don't know how I'd get a piece positioned properly with contact stuff.

There is a 564 distributor in Houston so I was able to just pick the stuff up. It cost me $70 for a 4 gallon pail. They don't carry 1 gallon containers. Guess I'll have a lot left over to glue AstroTurf on the decks of my boat and at least 10 others at the marina. The three women at the 564 distributor are into cats (the animals,not the boats!) and tried to get me to adopt one of the kittens that they find from time to time in their warehouse! One kitten sat on the keyboard while my order was being entered. Explains the typos on my invoice! I'll let you know how the installation goes. So far, so good!

I decided to apply the vinyl before cutting and installing, as the prospect of doing the vinyl after insulation seemed beyond my skill or patience level. I'll glue the seams, then stick on a white batten from Lowes using a 3M product for vinyl surfaces. The way I cut the sheets left me with only one seam in each cabin. I don't think that's too much of a distraction!
But I haven't tried to do the pieces for the roof of the V berth yet. Did you do that area and if so, how did you splice the pieces? Looks like several ways to do it.

[paulsproesser]

Sorry to chime in late but I wouldn't recommend the HVAC insulation Armacell or Armaflex as they will hold water. I am an HVAC technician by trade for 30 years now and I've seen it first hand. If I were you I would go with the thin sheet foam Ebb suggested and put it in with Vinyl Mastic made by Polyken. It comes on a 2 or 4 inch roll like duct tape but its thick with a removable backing and strong sticky but do your install in warm or hot weather to insure the bond. and theres only the mess of the backing to clean up and alot cheaper than liquid adhesives or epoxy .

[ebb]

Whot's in a number?
I'm amazed you found the carpet paste,
Also amazed that the numbers haven't changed since I got the stuff.
Guess that salesman I called years ago gave good advice.
$70? Can't beat $17.50 a gallon. Isn't that what marine stores get for a quart of fabric glue?

My pail spent a couple california years under the tent at the boat, really outside.
We do have in paradise a fifty to sixty degree temperature range.
Then recently found the 4gal back in my garage-shop. The black polypropylene bucket has a slightly
different, better designed lid than what we see on those white plasterer's pails.

The lid lips pull up going round but it's not easy, they do get persuaded from their very good seal.
Pail had in the past been opened & closed a number of times.
A good air seal because I found very little inside had hardened up. Only thin stuff on the sides. Take a spreader now and make a flat lake in the pail when closing it up.

Easily scraped that ancient crumby off and noticed that after all that time sitting
the bulk of eco greek yogurt had essentially NOT separated at all. Top inch or so was slightly looser, but mixed in with the body with no work at all. A quick test showed it had lost none of its gluability. Long term storage guaranteed.

For the cognoscenti, the open time we give the paste after applied to mating surfaces, is the secret.
Keep at the desk here a piece of vinyl cloth 564ed to a piece of ensolite that cannot be pulled away from each other. Really amazing how totally attached they are. Right to the very edge. Kept the pieces apart for too long - according to the guide - just to check out what would happen. With a finger touched the paste. Didn't smear, but still transfered.
The grab was instant, the pieces stuck, felt I still had the ability to whip it apart if I had to. Didn't do it. Probably had to use pliers.

On the boat I put stuff together wetter than we're s'posed to - to get some of that adjustment probability, which depends on temp and humidity..
The embedded paste that can't evaporate, finally sets up imco if the boat is warm and dry - but I'm not sure total bond is there. Probably doesn't matter.

The paste also sticks to itself. So if a border isn't sticking, a bit of extra smeared on and left alone to dwell in air a minute - will bond back together!


Great tip on the cutting.
Didn't know electric turkey knives were still available!
Can't finesse a utility knife like that baby. Remember foam mattress shops used them in the early days.
Certainly much smarter pre-applying the vinyl coated cloth to the foam.

I think you're brave to tackle the overhead in the V-berth. Altho it's not strictly necessary because the deck is balsa cored, it will dress it up.
[Befor I was thinking foam, spent days filling, sanding, filling, sanding, because I'm stupid, and hi-build priming and sanding the forward stateroom overhead and under the decks. the main bulkhead had been opened to view. Finally more or less matched the smooth looking effect of the main cabin liner in there - including under the deck ! ! Not the anchor locker!]
Kent, I'll bet you won't be able to vinyl or even foam the radical curves of the forecabin overhead. Only under the deck.

Using your paper patterns you can lay out the foam and edge glue pieces together with 564.
While the foam might take kindly to compound curves, I don't believe if it's covered in vinyl that it will bend like uncovered foam.
My coated fabric is bendy and floppy, but its memory is flat. It conforms only to simple curves. But maybe what you have done, by pre-attaching it to the foam, gives it more flex?
Depending on your materials. A waterborne rubber paint might do the trick instead of fabric. I personally didn't like the paint as a cosmetic.
A flexible rubber urethane might be pre-painted on the emsolite as well. More control working from the gravity side, better results.
Lay out vinyl fabric to cross foam seams. Can position vinyl so that joins are off to the side of the viewer- out of view. Seams in the vinyl - if you straightedge knife cut them, slightly tilting the blade so that when joined the cuts butt absolute tight because they're slightly undercut - will disappear.
Of course they can be battened, as you say, and come out looking absolutely professional. If professional is the upscale. Maybe I'd cut the hatch hole from a single piece of cloth so no seams are seen there. Still have to cut darts in the material.
The eye likes to get tricked, that's why gals use make-up, and wood gets varnished!
Good luck ! How about photos???

[Hull376]

I'm taking some photos so will be able to post at some point. I've played with the 564 yogurt and attached pieces of vinyl covered Armaflex to painted wood and raw wood. The raw wood dried much faster than the glue on the non porus painted wood. As you'd guess the non porus Armaflex dried more slowly as well. As it dries, the 564 changes color from cream to a translucent beige color. When dry, it turns gray beige. And it appears to be very very sticky when dry. I'm doing some tests to see how long to let it set up before losing the ability to slightly move pieces of insulation. Wait too long and it will stick like contact cement, no can move!

The Veeeee berth roof is problematic. I'll bend some material and see what happens. But I bet I end up covering only the undersides of the deck. It will be an isosceles trapezoid beginning at the chain locker, with two quadrilateral legs running on each side under the deck. Or at least kinda like that. Actually it will only look like these shapes after a few beers. Hey, I didn't miss geometry class in H.S.!

And the black canister is still in play. Tough to get the lid off the first time, but positively sealed up when replaced. Long live 564. Maybe the next 007.