TOPIC: quick question gluing floor ?

ok my last question for awhile. when i get ready to lay my floor i am going to use stainless screws deck screws into my stringers , but back when my boat was first built i dont think they had anything like liquid nails . i was thinking if i dont take my floor up anymore after glassing it then a bead of liquid nails,wont hurt and might keep the floor down. just a thought.
i am aso going to plastic bag my foam, i found some long thin bags and can tie them off. hoping to keep it dry if by chance i get water under the floor. so think about it ad let me know i have to cut the foam first and then resin the underside of the floor.

thanks billy.

Hi Billy, I've known several folks who used PL Adhesive to glue the floor down. It's waterproof when cured, and stays somewhat flexible - not sure about liquid nails?

Definitely seal the underside of the floor with thinned resin before laying it down, I chose to add a layer of csm to the underside for additional protection for the wood. Countersink the screw heads on top to allow sealing with thickened resin, add at least one layer of csm and/or biax on top?

What foam are you using? Closed cell foam won't absorb water, I guess I'm not following the plastic bag theory sorry.

Just my opinion, everybody's got one right?

Hello Billy,

What about glassing the floor down to the stringers using fiberglass mat and resin. This is how I have done my boats. It is how several manufacturer's did the boats when new.

Do as you feel best because it is as Mark said "everybody......"

Do they make waterproof liquid nails? I know they have a water resistant but that is not the same.

IMHO polyester resin without CSM is pretty much useless. Thinning it is even worse since it breaks down the chemical characteristics of the the resin and it strength. If you want to seal the wood you would be much better off using a combination of boiled linseed oil, mineral spirits and polyurethane in a 30/4030 mix and letting it dry for 48 hours. When poly fully cures it is very brittle by itself and will crack when flexed and allow water penetration. Poly contains styrene which breaks down the fibers in CSM which then acts as binders for the resin to keep it from breaking when it flexes. Therefore I believe you should always use CSM when using poly resin in boat repairs. Anyway that's just my 2¢.

Since you guys are already talking about gluing a floor down, how about attaching a floor to fiberglass stringers? I've seen a mid-60's Glasspar that had factory fiberglass stringers, approx. 4" high & 3" wide, hollow underneath. Didn't seem like there would have been much meat there for a screw to bite into. The old floor had been removed when I saw it, & it didn't look like any damage was done to these stringers when the old floor was removed. Some kind of adhesive or resin maybe?

Glasspar glassed their floors to the stringers using fiberglass mat and resin. No screws. Fiberglass stringers on Glasspar appeared in 1963/4 models before that they had wood stringers with the floor fiberglassed to the stringers with fiberglass mat and resin.

I was just about to post a similar question I remember someone making a post several years ago they used a pl product to bed their stringers down with and was wondering which number he used getting ready to put the Flore in my Larson that I am converting to center console

Charles

I replaced a section in my bow I used the chopped fiberglass (tiger hair) to bed mine with. It is still there and has not moved a any. My internal wooden keel had a piece that was questionable and I replaced it.

I use 3M 5200 to bed/glue everything then fiberglass the entire deck and up the sides of the hull to a height of about 4".

Ditto on the 3M 5300. It will far surpass anything else used, including screws. Do NOT put screws in the floor - they will invite rot, even if you glass over them. Do not use any PL / liquid nails / etc!!!!!! They are not designed for flexing and will crack. Trust me, I've tried them and they don't work. Using mat and resin to bond the plywood to the stringers is how it was done originally, and it was a mediocre bond at best. Get some 5200 - the big tubes for a caulking gun - and lay a big BIG fat bead along the the tops of the stringers. Drop the plywood into position & put some weights on the floor to press the wood into the glue. Walk away from the project for 2 weeks. The "standard" cure 5200 requires humidity to cure, and it usually will take 2 weeks to set up completely. If you want, there is fast cure 5200 that will set up in a couple days, but it's more expensive. Either way, it's best to leave the floor alone for a couple weeks to let the stuff completely cure. Move it too soon & the bond can be torn. Once cured - that floor will be bomb proof (literally)

I'd go with that, my area was just a small piece and it is in the open and not to be sealed in. In fact two years I installed a 1/2 inch wide and 3/8 thick steel runner on the outside that screwed into that wooden keel. Now I show no fiberglass damage in two years of use in grounding.

has any one used something like Thomsons water seal for decks on the under side of your floor to seal it
Charles

Thompsons is a wax base mixed in a light solvent to keep it soluble. The solvent dries and leaves the wax behind.. It's probably the worst product you can buy for anything

can any one recommend a product to use the mixture that Flamingo
suggested sounds good but would like something pre maid if possible am planing on using 5200 to glue the floor in and foaming
under the floor
Charles

The manufacturers of Thompson's Water Seal should be prosecuted. That product is complete and total crapola. It's wax in suspension. When it gets hot, it melts and catches dirt and anything it touches like flypaper. I use CPES exclusively...clear penetrating epoxy sealer.

I've pretty much seen it all...green treated plywood, deck stain, Elmer's Glue-all, interior latex paint, roofing tar, plain old steel screws that rust overnight, kitchen linoleum and even shag carpeting.

Best advice I can give anyone: When working on boats, use marine products.

I use CPES and PL polyurethane adhesive. I formerly used 5200, but have had better results with PL polyurethane adhesive. And it's a LOT easier to use.

is there any one that has cpes like a big box store that you can go to
Charles

Jamestown Distributors (and advertiser here, see the box in upper right hand corner of the screen) had it on sale not long ago, I'm sure they'd be glad to ship it to your door too!

I found 3m 5200 at lowes for under 10.00$ a tube and if you buy 5 0r more tubes you get free shipping and if you use their card you can even get more off
Charles

Billy don't want to hijack your thread but since we're on the subject, let's get some info. Does anyone know how well the 3M 5200 sticks to CPES'd wood/ply? I've heard that the 5200 doesn't like to stick to the CPES'd wood. Some of the woodie resto guys are not CPESing the frame side of the planks until after it's bedded into the 5200 because, supposedly, it won't stick.

Thoughts folks, Nautilus, Gary?

Bob

It has been my experience that 5200 sticks to everything. Granted, it may stick better to bare wood than wood coated with CPES but it still sticks...the difference being inconsequential. Actually, I can't think of a situation when 5200 coated pieces aren't held in place with screws. I have never seen anything held together with 5200 come apart...ever! Removal always requires destruction.

Another thought...CPES needs time to cure. It does not cure overnight. I would guess that 5200 applied to wood that is still wet with uncured CPES would have a problem with adhesion. The people who wait to apply CPES until everything is assembled with 5200 may just be doing so to save time and keep the project moving along.

In conclusion, you're either using 3M 5200 or you're using something inferior. I put it on everything but my food. 5200 rules!

I just bedded my stringers in with 5200 now waiting for 2 weeks to cure then glass them in guess will have to order more to glue the floor in used almost 4 tubes how much CPES should I buy to coat under my floor it is a 17 foot larson what is the best way to apply it
Charles

I'd be very interested in hearing the justification for using CPES and 3M 5200 for bedding Stringers and Gluing Decks, as opposed to using, Poly Resin & Or Epoxy.

Both Products are way more expensive.

I'm a C.O.B. and try to use the least expensive items while not giving up good quality.

Supposedly, CPES IS epoxy sealer. As for the 5200, I like things put together that can't crack or break apart. Fiberglass resin is rock hard but it will crack and/or break away under stress. 3M 5200 allows "wiggle room," although the wiggling is extremely minimal. If you glue two pieces of wood together with poly resin and let it cure, you can swat one of them with a hammer and break the bond. If you try that with two pieces held together with 5200, you'll wear yourself out and end up with mashed up wood...that's still stuck together.

When it comes to expense, I spare none. I feel that there is absolutely no room to compromise on the "foundation"...boats, buildings, whatever. I buy the best material available...not the most expensive, the best. The cost "is what it is" and to me, it's irrelevant, particularly when weighed against the cost of the labor to do the job, which is generally the same regardless of the materials used. When the job is finally done, saving $100-200 on material not only seems unimportant, the little nagging doubts I have (used to have) make me wish I'd spent the money.

Of course, being in the restoration business, I pass the material costs along to the client (at my cost) but I've never had a complaint about the price of material or had anyone tell me "My decking is too solid."

"I'm easy to please. I'm always satisfied with the best." - Oscar Wilde

CPES is Clear Penetrating Epoxy Sealer. It is purely a sealer with the objective of soaking into the fibers of the wood to "plasticize" it. It is very thin, almost like light oil, and has a proprietary mixture of ingredients to allow it to soak father into wood than other more viscous products. It does a great job of sealing wood, especially before the application of other resins or paint. I used it on the new raw wood trim boards of my house to prime before painting. The paint on that trim has held up better than any other exterior paint on the house. This is because the wood had been effectively sealed. It really is good stuff.

Gluing with 5200 Marine Adhesive is less work than bedding with multiple layers of mat and poly, or with thickened epoxy. It also has a huge benefit of serving as a cushion between the structural member and the fiberglass hull. This prevents "hard spots" on the hull, which can result in stress fractures developing under the stringer or other "hard" structure. Since fiberglass flexes, the glue has a very slight "give" to prevent these stresses. This is especially important in hull structures that are lightly built (thin) as most 1950s - early 60s boats were built. Originally, builders did not "bed" stringers with resins, because they wanted to avoid hard spots. The would simply set the untreated wood into the hull, then slap some tabbing on to the sides to bond it to the hull. There was no bonding on the bottom edge of the stringer, and often, there was a small gap between the bottom edge of the stringer and the hull. This provided some flexibility, which was a good thing. But, water would become trapped in the space under the stringer and rot would happen. This is why good builders were quick to abandon wood stringers in favor of molded fiberglass stringers.

Just because the boats were built with available products at the time, doesn't mean that those are the best things to use today. 5200 in bulk from a jobber is actually very inexpensive for how well it performs and how much time it saves.

I appreciate both of your responses. I always like to learn from the experiences of others. That's where I've gained most of my knowledge. Here's my take and 2¢ on the subject of bedding stringers. Poly resin by itself is useless as an adhesive. When cured it is brittle and will break with minimal flexing or impact. We all agree on that. However when a binder is introduced to the mix, the resin quickly takes on characteristics that make it suitable for adhering and filling substrates. Cabosil and chopped milled fibers suit the bill for this, as well as CSM. I use this to afix my transoms to the hull and to bed my stringers. I've never had issues with "Hard Spot" crazing and I put the "Goop" in a large Gallon zip loc bag cut off one corner and use it like a Pastry Bag to apply a nice bead of the mix to the hull to set the stringers in making is quite easy to apply. Using a 1% mekp gives me adequate working time as well. @ $27 per gallon I have not found anything less expensive or better to use. I've attempted to use PL Adhesive which is similar to 5200 but Like 5200 Poly and epoxy does NOT like to adhere to it so when attempting to tab over the inevitable smears and globs it was problematic and I found myself grinding and sanding those areas again. Staying with the same family of products seems to make things much easier. I agree, if we were making larger vessels or ones meant for Heavy abuse we might consider alternate methods of construction. For me, Bedding with "Peanut Butter" is more than adequate on all counts and creates no issues for the hull. Compared to what the original MFG's did it's major % points ahead of what they did.

Thanks again for your insight. The 3M 5200 is some "BAD" Mojo stuff and I use a lot of it for sealing mechanicals etc...

As for CPES, I have a friend that's one of the leading consultants in the U.S. in the Poly and Epoxy manufacturing industry. He conducts seminars in the U.S. and Canada on a regular basis speaking on the chemical properties of the products and how to best use them in the boating industry. He tells me that any time Epoxy or Poly is thinned with a solvent, it has a severe negative effect on the chemical properties of the resin and should be avoided at all costs. When it comes to boats and the wood in them, it's all about encapsulation. NOT penetration into the wood. If the wood is properly encapsulated in the resin, and this "Capsule" is not broken, then the wood will be preserved indefinitely. Has noting to do with whether or not the resin has penetrated into the wood or is laying on top of the wood. He tells me CPES is just another "Gimmick" and that we all would do just as well by warming our resin with warm water and then applying it "Full Strength". Just thought I'd pass that along. I can have him come on the forum and pass on some info if you'd like. He might already have been here. He's posted on almost all the others I've been on.