Glueing Foam core to Mountboard

[RobM]

On a project where I'm using a float mount, I've attached the artwork to a mountboard (of a slightly smaller footprint of course) with tape, which I then tried to glue to a sheet of foam core using PVA.

After letting it glue overnight, I tried putting the frame together today - only for it to come off the foam core.

Should I be using a different glue to make this stick better?

[RobM]

I should point out that my foam core is just slightly less the footprint of the mountboard, as shown here.

I was interested watching this video, whereby they just used a few small squares of foam core - is the better method?

[Justintime]

That grid pattern suggests to me that what you are using is not standard foamboard but a self adhesive coated foamboard but you are trying to glue the removable facepaper of the self adhesive board to the black mountboard. I believe those face papers have a waxy coating that prevents them from attaching to anything.

[JKX]

What’s the square pattern? (Edit - just seen Justin’s post - agree!)

[Justintime]

Personally I prefer to use a full piece of foamboard as you are attempting to do as I think it gives it more rigidity, but Roy uses little squares and it works. I would also say that it depends on the size of the piece. A larger piece I think the likelihood is that if the back mountboard warps at all it will be more of an issue. I think I'm trying to say that a larger piece of foamboard may prevent any warping issues of the back mountboard.

[RobM]

Just checked and...you're right! I'd never realised it was self adhesive.

That grid pattern suggests to me that what you are using is not standard foamboard but a self adhesive coated foamboard but you are trying to glue the removable facepaper of the self adhesive board to the black mountboard. I believe those face papers have a waxy coating that prevents them from attaching to anything.

[JKX]

When you use the right board you don’t need all that DS tape, I’d use just a few dabs of it only to hold things still while the wet glue dries. If you use that self adhesive board, apply some dots of glue too. It’s pressure sensitive and you cannot burnish another board to it.

[RobM]

I actually only put that tape on after I found the glue had failed. I was going to fix it but then decided not to.

The advantage of glue in these situations over tape (and the adhesive on these boards) is that it gives room to move it into place a bit. I'm not completely confident that I will drop it onto the backing mat perfectly - and tape won't allow me to adjust it, like glue will.

When you use the right board you don’t need all that DS tape, I’d use just a few dabs of it only to hold things still while the wet glue dries. If you use that self adhesive board, apply some dots of glue too. It’s pressure sensitive and you cannot burnish another board to it.

[JKX]

You can use your mount cutter to lightly score the board’s position, or plot it in pencil.

You should be able to reposition DS tape, by lifting if not sliding, until you apply final pressure, especially if just using it as I described.

Hope you can tie this in with the rest of the thread without me quoting you

[Justintime]

The advantage of glue in these situations over tape (and the adhesive on these boards) is that it gives room to move it into place a bit. I'm not completely confident that I will drop it onto the backing mat perfectly - and tape won't allow me to adjust it, like glue will.

Yes, you can just glue and weight it in position, go off for lunch and carry on when you come back. When I have to position something very accurately I cut some board strips to the border measurements for the left and bottom, clamp them into place, then place the work exactly and weight and leave. Or weight and wait!