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Basically:

I want to build some cabinets. Locally (Indonesia) there is 'cheap and nasty' 15mm plywood available, plus 15 & 18mm phenolic plywood. I tried ordering some 'slightly nicer' 18mm plywood, but it's apparently not going to come.

So I am looking at using (black coloured) phenolic, which for some purposes I will leave as is, but for others I will want to stick high pressure laminate (HPL) on it so it's not all black.

Question is: normally here we would use neoprene glue for HPL to plywood and basic white PVA glue for plywood to plywood, but will they work for phenolic? (Obviously in some cases the phenolic will probably get sanded off or rabbeted or whatever, so in that instance it's not an issue, but in other cases it will be.)

Edit: there appears to be some confusion about what plywood I'm referring to. Here nobody actually knows what it is called as it is called 'Garuda form', where Garuda is the brand (or was?), and 'form' refers to concrete formwork (it's often spelled/pronounced 'foam' here, because people here don't speak English so such homonyms aren't surprising)

Here's a fairly representative photo of a (12mm) version which looks kinda scratched, which is pretty much the state of the stuff I saw on sale as well:

enter image description here

Although nobody actually knows its formal name here, it is my understanding it that it is indeed generally referred to as 'phenolic plywood', and I'd guess that the quality of the wood itself isn't all that high although the phenolic that's on the outer faces means that it's much more durable for formwork.

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  • If I understand correctly, "phenolic" refers to a resin that that's basically a plastic, is it not? If so, you'd need some sort of plastic glue and I'm thinking CA would do the trick. Does this mean your "phenolic plywood" is actually a sheet of plastic, or is it somehow "phenolic impregnated" helping to make it water resistant/proof? Some additional info or a link to educate those of us less knowleadgable would be appreciated.
    – FreeMan
    Dec 17, 2021 at 18:25
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    Yes, make sure we define our terms here. So-called "phenolic plywood" is what some would just call plywood (but, you know, the nice stuff) or just birch or oak laminate, depending on the type. Though it can be faced with almost anything. The classic example is so-called Baltic birch. If this is the case then it really isn't made out of "phenolic". The veneers are soaked in phenolic resin before attaching them to the plywood. for the case of actual wood veneers PVA glue works just fine. But we need to know what you have.
    – user5572
    Dec 17, 2021 at 18:34
  • I don't know if your "neoprene glue" is the same as the contact adhesive I mention in my Answer, but most contact adhesives are based on rubber and as you already use it for HPL I am presuming it's the same thing.
    – Graphus
    Dec 17, 2021 at 23:25
  • The phenolic plywood is waterproof glue, while HPL plywood is moisture proof glue. Phenolic plywood is for outdoor use, while hpl plywood is for bathroom and kitchen cabinet and other furniture use Jun 18 at 14:06

3 Answers 3

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Contact adhesive is generally what you'd use in a home workshop environment to glue high-pressure laminate to any substrate, and it will work here too. The bond may not be super durable, but this is the adhesive of choice for many people today laminating over old Formica and melamine surfaces which are similarly resistant to conventional glues.

Surface prep
I'm unclear on whether sanding/scuffing the surface of the phenolic will actually help improve bond strength with this type of glue. This is a desirable, even necessary, step to maximise adhesion with many glues but contact adhesive works in such a different way to other glues that 'rule' may not apply.

It would probably be advisable to do a few tests to see if the cleaned, but otherwise untouched, phenolic surface bonds better as-is or after giving it a thorough scratch pattern via sanding or use of an abrasive similar to Scotch-Brite. Abrade with more than one grit to check if coarse scratches or finer scratches provide the best bond, or if there's no difference.

IF you find sanding strengthens adhesion (and I wouldn't be surprised if it doesn't) my guess is there'll be no difference between about 80 and 150 grit, but beyond 220 you may begin to see a decline.

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After a brief internet search to determine what "phenolic plywood" actually is, I turned up this:

Phenolic plywood is somewhat of a misnomer as it should more realistically be called “phenolic faced plywood” or “phenolic covered plywood.” The veneer core plywood itself isn’t made of phenolic; it’s generally made of birch. What makes it “phenolic” is that both surface veneers are soaked in phenolic resin before attaching them to the plywood. This creates an extremely stable, smooth, durable, highly water resistant and attractive surface
Source: http://theplywood.com/phenolic

That same site also says:

Building things out of phenolic plywood is much like working with other types of plywood.

Then goes on to describe cutting, sanding (don't sand the face, just ease the edges as the plastic coating can leave a very sharp edge) and screwing (it's very good at holding screws).

Since the core of the plywood is standard, cabinet grade plywood, it would only stand to reason that standard plywood construction techniques apply. Regular PVC glue on the wood/wood joints, regular screws, etc.

The one difference I can see is if you're slipping the phenolic plywood into a dado. In this case, I can definitely see a benefit to sanding the coated outer layer off where it will go into the dado, then cutting the dado a fraction narrower to account for the loss of the surfaces. This would give you a wood-wood bond for the glue inside the dado. Even if you don't do this, you'd still have a wood-wood bond at the edge of the panel against the base of the dado and would probably still be good to go, especially so if you screwed through the dado into the shelf piece.

Additionally, since the phenolic resin impregnated outer layers are already laminated with plastic, I'm not sure why you'd want to put an additional layer of laminate on top. However, I believe that a very light scuff sand of the surface to be laminated to give it some tooth, then standard contact cement would probably hold just fine, just as it would if you were laminating standard plywood.

I would suggest, though, that if you're going to be laminating surfaces, you might consider making those surfaces out of a less expensive, lower grade plywood since you'll be covering any ugliness in the surface layer with the laminate.

If you're laminating to change color, the site above noted that phenolic plywood is available in many colors beyond brown and black, but that these other colors may have to be special ordered. You may have no choice but to apply a laminate if you want some sort of a patterned surface.

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  • It is unclear if the OP is using the common veneered void-free laminates referred to here, because they mention black coloured veneers. They might not be using plywood with an actual wood veneer. I can assure you that the birth or oak veneered laminates that fall into this category behave just like plywood -- even the surface. Not "plasticky" at all.
    – user5572
    Dec 17, 2021 at 18:39
  • True, @jdv. The site I linked does mention that usually it's over a high quality cabinet grade ply and that the surface is usually resin soaked wood, but that other options are available, as are other colors. (I was just about to make that edit as your comment popped up.)
    – FreeMan
    Dec 17, 2021 at 18:42
  • Or it might be an "Ikea halo" effect, where the need for relatively strong void-free laminates that can be machined into various flat-pack items has led to factories selling the black and white wrapped stuff along with the usual Scandinavian look wood veneers.
    – user5572
    Dec 17, 2021 at 18:50
  • It seems it would be most appropriate to comment on the question itself to get our OP to describe in more detail what he's using. In either case, though, it seems that PVA wood glue would be appropriate for adhering wood to wood.
    – FreeMan
    Dec 17, 2021 at 18:50
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Based on the description of the "black-colored surface" I'd guess that the OP is not referring to the "furniture grade" stuff, but rather the "industrial" stuff that's commonly used for cement/concrete molds, the lining of agricultural enclosures, marine structures, and shipping containers, etc. Where durability and high water resistance is desired.

Not sure of exactly how the formulation of the coating is any different between the two, but the "furniture grade" stuff is built with essentially Baltic birch plywood and the phenolic (essentially plastic fused to the wood fibers) coating that comes in a variety of pretty colors. (Undoubtedly one of them is black.)

The factory impregnates the fiber surface of the "industrial" stuff with a thermosetting resin and then bonds the resin fiber surface to both sides of the board with heat and pressure with inter-ply construction of C or C-plugged veneer. Face veneers are B-grade.

As far as gluing to the phenolic surface, TiteBond makes a glue for Melamine that might work on Phenolic surfaces as well. You may want to scuff the surface before trying to glue it.

I also understand that abrading the mating surface with sand paper and using moisture-activated polyurethane adhesive (e.g. "Gorilla Glue") will work but PVA and epoxy will not.

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  • Why do you say that epoxy will not work? It's perhaps not a suitable choice here for other reasons but ability to bond shouldn't be one of them, after suitable surface prep.
    – Graphus
    Dec 17, 2021 at 23:29
  • @Graphus - Same guy that told me Gorilla Glue is the one to use. Apparently epoxy just kind of pulls off after a while. I don't have first hand experience gluing the stuff, but at one time I considered buying a couple sheets for shop surfaces, etc. and was asking about working with it at the lumberyard.
    – gnicko
    Dec 17, 2021 at 23:35
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    OK well two things: first, don't take what anyone tells you as gospel (I've learned the hard way that this includes pros but it goes double or triple for some random person of unproven authority) and second, I believe there's a huge difference in bonding phenolic sheet to substrates, and bonding to the phenolic. The front side and back side of phenolic are very different, no? Regarding sticking it to other stuff, see this, How to bond phenolic – Successful phenolic bonding
    – Graphus
    Dec 18, 2021 at 0:21
  • @Graphus - Good advice. A guy who uses the phenolic plywood daily (or almost daily) is hardly a "random person" but I never suggested that it was gospel either. I even offered that I didn't have first-hand experience with it. I hadn't considered specialty products for gluing to phenolic surfaces, but from what I gather, bonding the stuff to the plywood substrate is a matter of heat and pressure. It's baked in.
    – gnicko
    Dec 18, 2021 at 1:09
  • Apologies if what I said previously came across less well than intended. But you see the significance here? By any reasonable definition that guy is a pro, and yet he was wrong about the epoxy.... it makes him literally the poster child for what I was talking about. I'm calling this my "don't trust, and verify" philosophy, and it's the most significant realisation of my life.
    – Graphus
    Dec 19, 2021 at 9:21

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