Hello,
I've cast a thin slab in glass fiber concrete, which I've done many times before, but now I wanted to try mounting it on the wall. I won't go into more detail as to why, etc.
The slab, as mentioned, is cast in Glass Fiber Concrete A from Finja and is about 20 mm thick. All sides are smooth except for the back, which was the side left open in the mold.
The wall is brick with plaster on top, so it's the back of the slabs that is against the plastered wall.
I used an adhesive from Bostik called MaxiBond Extreme which is supposed to be very strong and suitable for this.
I get a decent attachment, and the slab absolutely stays on the wall, BUT I can tear it down with a bit of effort. I want it to be much more secure.
The PROBLEM, as I've understood it, is that when you pull the slab off, you can see on the adhesive that the outermost "ballast" or "grains" from the glass fiber concrete slab come off with it. To explain simply, think of trying to glue onto sand; it doesn't hold because the "grains" in the sand are loose and just come off. This is the same principle, the adhesive can easily be pulled away as it only adheres to the outermost "grains" that aren't held together very well. Since glass fiber concrete is like this all through, it doesn't matter what I do with the surface, it will always have a "grainy" surface.
It feels like the solution is that I need to treat the slabs in some way to make the surface hold together better, or somehow make the surface more uniform so that the adhesive doesn't just stick to the outermost "grains."
So, what should I use for this? Some kind of concrete primer? Binder? There are countless products, and I'm having a hard time knowing what to treat the slabs with. But somehow make the "ballast"/"grains" on the surface adhere better to the rest of the slab.
I hope you understand what I'm trying to explain; I realize my description wasn't easy to read.
Thanks very much in advance.
I've cast a thin slab in glass fiber concrete, which I've done many times before, but now I wanted to try mounting it on the wall. I won't go into more detail as to why, etc.
The slab, as mentioned, is cast in Glass Fiber Concrete A from Finja and is about 20 mm thick. All sides are smooth except for the back, which was the side left open in the mold.
The wall is brick with plaster on top, so it's the back of the slabs that is against the plastered wall.
I used an adhesive from Bostik called MaxiBond Extreme which is supposed to be very strong and suitable for this.
I get a decent attachment, and the slab absolutely stays on the wall, BUT I can tear it down with a bit of effort. I want it to be much more secure.
The PROBLEM, as I've understood it, is that when you pull the slab off, you can see on the adhesive that the outermost "ballast" or "grains" from the glass fiber concrete slab come off with it. To explain simply, think of trying to glue onto sand; it doesn't hold because the "grains" in the sand are loose and just come off. This is the same principle, the adhesive can easily be pulled away as it only adheres to the outermost "grains" that aren't held together very well. Since glass fiber concrete is like this all through, it doesn't matter what I do with the surface, it will always have a "grainy" surface.
It feels like the solution is that I need to treat the slabs in some way to make the surface hold together better, or somehow make the surface more uniform so that the adhesive doesn't just stick to the outermost "grains."
So, what should I use for this? Some kind of concrete primer? Binder? There are countless products, and I'm having a hard time knowing what to treat the slabs with. But somehow make the "ballast"/"grains" on the surface adhere better to the rest of the slab.
I hope you understand what I'm trying to explain; I realize my description wasn't easy to read.
Thanks very much in advance.
