HELP with backing board


CGF II, Certified Grumble Framer Level 2
Mar 4, 2003
Richmond Hill, Ontario, Canada
We use archival fome board as a backing board for framing paper artwork.

We usually stay clear of shallow frames, however, there is a very nice moulding with a very shallow rabbet that we would like to try; there is no room, after matting and glazing, for fome board (even 1/8"). Also, in this instance, increasing the rabbet size is not an option...

Is there any disadvantage, or foreseeable future problems, in using 4 ply Alphamat or rag board as the sole backing?

* The items to be framed are only 10" X 10" and 10" X 12". Even so, I'm a bit concerned that matboard might not be stiff enough?

Thanks all!
The Bainbridge Alphamat is not a very rigid product. I have done what you are asking many times before with mixed results. The Artique matboard from Larson is much more rigid and will do the job nicely. Being that they are only 10 x 10 in size, the Alphamat may work just fine. I would try it.
I tried getting away with 4 ply as a backer once, because of a shallow rabet. Did not work, had to use foamboard.

It is not an option to use RabbetSpace for your project?

I wonder about Plexi perhaps?

Hmmm, I back to 4-ply Alphamount or RAG all the time. I then use a filler of Artcare foam or Rag. In the rare case where I have a very thin (say 3/8" and they want a double mat) rabbet and the total size is not "too large" I have left just the 4-ply rag. (I use the rag because it does seem stiffer the than the B8734 Alphamount.

I recently got one back for a broken glass after about 2 years and it was fine. (aside from the glass. :D )

Mike, What exactly "Did not work?"
Originally posted by Cliff Wilson:
Mike, What exactly "Did not work?"

My bad, I think I misunderstood the question. I thought the question was about using 4 ply for the filler board to save space.

Of course 4 ply works for the backer. Sorry for any confusion.

Since this does not sound like a case in which the
frame can be deepened, you can make backing boards
our of Coroplast or Cor-X that are thinned at their margins so that they overlap the back of the
frame. This can be done by cutting the backing
material so that its outer edges are larger than
the rabbet dimensions of the frame, but smaller
than the outside of the frame and make a shallow
cut into the skin of one side of the board,
slightly inside the rabbet dimensions. One can
then cut through the flutes and remove the skin
and flutes that are cut off. The resulting board
will be solid in the rabbet area and will have
a skin on one side that will lap over onto the back of the frame, where it can be secured with
screws or staples.

Is Cor-X acid free? What about out-gassing?

Dave Makielski

Is there any reason to be concerned about the flutes leaving a pattern in the mounted art? If it is a watercolor on thinner paper, I would wonder if the pattern wouldn't show through the paper in time.

Other than that, your idea is excellant and one that I hadn't thought about.

First of all, try to use a frame that's appropriate for the peice, but...

If the package, including the ArtCare foam board, is not flush with the frame, I use the same off- set clips as for a canvas, then hide it all behind backing paper.