>I'm going to be making a counter top out maple....configured as end-grain butcher-block.
About three feet by two and a half, and about 2 1/4" thick.
I'm thinking West System as my adhevise for it's superior bond, as well it's water-proof qualities..I figure using epoxy will help with humidity not getting into the wood as much, causing havoc over time...considering how big this is, I want it to stay flat.
But then I think about food-safe properties.
I could always simply use a cutting board on top of this countertop when cutting foods. I think that the butcher block top is more for looks that the actual utility of using it for cutting foods.
>Titebond III is waterproof and food grade once cured. I've made a couple cutting boards using it and have had no problems with them. If I was going to build one into my counter top, I believe I'd make it removable. That way when it was all cut up and had that hollow in the middle I could turn it over and eventually replace it. My .02 cents worth. Taht and another three fifty will get you a coffee at Starbucks. Less the tip of course.
>Ted , I am not sure if inert is what I would be thinking about. I use a good bit of epoxy, and guess I am pretty well versed with its use. I don't use it for just edge gluing. There are better glues for this. Epoxy is long chains of molecules which are too big to penetrate the cell walls. It needs a more textured surface to latch onto. so on a dense even textured hardwood like maple, where the whole project is basically edge gluing, that would not be my first choice. I would just go with something like the tightbond two or three for the gluing.
However If you are wanting to use the epoxy to protect, and keep the moisture out, You may want to think about using some of the thin epoxies that are made for penetration, and are used in wooden boats where you know it is going to get the worse exposure to harsh conditions.
I can give you about 4 sources or different brands, but the one I use is
http://www.fgci.com/ They have the best price that I have found. If you can do something to dam the perimeter. maybe just use tape, so that you can flood the face without worrying about it running over the edge. I would try to warm up the face, like setting it under a heat lamp or infrared source, then mix up a batch, and flood the surface, and let if draw it in while it cools down. This would improve the penetration over just brushing it on at ambient temperature.
These penetrating epoxies don't cure hard like most epoxies, they end up a lot more flexible, which would be a good thing for this. I think you would end up with something looking more like an oil finish, but much less permeable.
Well, don't forget that this is an endgrain butcher block...the glueing surface will be face grain so the endgrain is up and is the cutting surface.
You mentioned thin epoxy. Do you have any problem with using standard West System and just using lacquer thinner to thin it out? Do I sacrifice some bonding power by doing that?
>I have not dug deep enough into this, but I suspect that anything they print on their container or literature reflects their compliance with whatever standard governs water resistance. My understanding was that they met the most waterproof standard.
If you have further light to shed on this, be specific. Meanwhile, I will invite Franklin to chime in....
>I have never tried thinning it on my own. The last thin 2 qt kit that I bought from fgci was less than $30. I think of that as "peace of mind insurance".
I would not use standard epoxy as a coating for your purpose, because it would likely get chipped and be hard to maintain.
>TB III passed the ANSI Type I specification. That is the spec that defines "waterproofnes" or an adhesive that can be used in totally submerged, long term applications of varying temperatures. In other words, there is no water application where it would not be appropriate. It's as "waterproof" as rescorcinal and more "waterproof" than epoxy which softenes and loses its adhesion at higher temperature.
You can go to the Titebond site (www.titebond.com) for a description of the ANSI/Type I spec and the ANSI/Type II spec. The Type II spec is the one the TB II meets. Is is a less stringent spec for "water resistant" adhesives.
>The West System stuff is plenty thin as it is. I used it on a number of things I built out of ipe some years back (custom deck gate, massive planter box, etc.). You can 'paint' the surface with epoxy and a thin coat soaks right in. I used a microsphere filler additive, and IIRC, I 'painted' the surfaces to be joined with straight epoxy (and it soaked right in), then went back with the thickened epoxy to glue the joint.
I'm not sure how exercised I would get over the 'waterproofness' of epoxy v. titebond III v. polyurethane, as if counter top is soaked so much as to break the titebond III or the polyurethane, you've got much bigger problems.
>A point about epoxy. Unlike waterbased adhesives, epoxy gets its strength from a film thickness in the glueline. Apply too much clamp pressure and you will squeeze all the epoxy out and end up with a weak joint. You have to be very gentle clamping epoxy.
That said, epoxy is not a good choice for a cutting block or cutting board. For that type of application you want to be able to clamp very tightly to minimize glue line appearence. The best adhesive for chopping blocks is a Type II PVC adhesive like Titebond II. While epoxy is inert, and therefore non-toxic when cured, so is a PVA adhesive.
Let me close by saying the making and endgrain countertop is a big job. When I get home later, I will post some info about how to go about it.
