Need help to resolve the "trampoline effect."

[Karin Wells]

I need some helpful advice. I don't like the much-too-bouncy "trampoline effect" I am getting on my stretched linen canvas 30" x 36" and larger).

I would like to attach a largeish linen canvas to a 30" x 36" lightweight rigid support. This has never been a problem when I use cotton canvas.

The rigid support needs to be lightweight because with a thick layer of paint the framed painting is much too heavy (not to mention the problem with a frame holding something so heavy). Foamboard is not archival -so I cannot use it- but I like the weight of it. MDO board is wonderful but is heavy in this size. Also, Masonite hasn't stayed flat after the canvas is attached.

I have tried attaching this large linen canvas to various substrates with gesso and I got a bubble. I have also tried Elmer's glue with the same poor result. In addition, I had poor adhesion with these two "glues" and could have easily peeled the canvas off when dry.

So far, I have used the two "glues" mentioned, flattened it successfully with a rolling pin, and put heavy weights on it until it dried. However, I am very disappointed when it is dry.

I have even tried painting on the canvas pinned to a board and attempted to stretch/glue it after I have finished the painting - and this is also unsuccessful.

Frankly, this extreme "trampoline effect" is driving me nuts. The part of the country I live in varies greatly in temperature and humidity and my linen supports bag, sag, and tighten accordingly.

Has anyone out there resolved a problem like this?

Do I simply need to limit myself to a cotton canvas on large paintings and avoid linen?

[Michael Georges]

Karin:

I use .25 inch Masonite almost exclusively. I accept the weight as my process is better served with a rigid substrait.

I have glued canvas and linen to masonite with good results. I don't recommend using Elmers glue as they add corn starch as a filler, and the acrylic polymer they use is very cheap. Within 25 years, Elmers will separate into its parts and powder on you.

I have used pure acrylic polymer medium with good results, and also Gamblin PVA with good results. I sand the board very heavily with a rough paper, coat the board with the polymer or PVA and lay the linen on. I get the linen completely soaking with the glue. Roll it out with a rolling pin. I leave at least 8 inches of linen on all sides hanging over as I do a wrap around glue. When the front is dry, I do the same thing to the back with the flaps and glue and wrap one side at a time (trim to get even folds). The wrap helps tame the warping of the board.

I then seal the entire thing in at least three coats of gesso - front and back.

Another option you could consider that might be lighter than masonite is sheets of PVC plastic.

Are you objecting to the trampoline effect when you paint? If so, then you could continue to use canvas, but slide a backing board of foamcore behind the canvas which would help with the spring.

[William Whitaker]

Karin,

I love linen, but the contraction/expansion problem drives me crazy too.

I

[Marta Prime]

Has anyone ever experimented with painting on wood? I saw some beautiful portrait paintings in gallery's last time I was in Sedona, AZ. They were painted on wood. I suppose painting on wood is one step away from painting on velvet in this industry! At least it wouldn't "bounce"!

[Karin Wells]

Wooden panels are wonderful to paint on if your painting is to be small. But my problem would be finding them big enough. Also, in a larger painting, the weight of wood and its tendancy to warp can be a big drawback.

[Karin Wells]

Here is the answer I needed thanks to Virgil Elliott in another post at:
http://forum.portraitartist.com/show...id=887#post887

Virgil shared the following information (edited for brevity - but you can see his original posting for the complete text)....

MuseuM Services Corporation, in Minnesota, makes honeycomb aluminum panels. They are light in weight, thus suitable for large paintings. The same company also sells various types of panels with canvas glued to them with a conservation adhesive, ready to be primed. MuseuM Services Corporation has a website at: http://www.museumservicescorporation.com.

Sometimes Virgil glues his canvas to John Annesley