Shrinkage of canvas when mounted to Gatorboard

[ghaynes754]

So here's a bit of a twist on this subject.  I've started mounting to 3/4 Gatorboard.  Just did a show and found that while my paper prints (Lexjet Metallic) looked great all of my Canvas prints (Hahnemuhle Monet sprayed with EcoPrintshield) has shrunk on the Gatorboard leaving a pretty much even edge gap between the edge of the canvas and the edge of the board.  I use a Drytac cold laminator with the Drytac Bestmount adhesive. Bestmount is white so now I have a not dis-pleasing white border around the print. 

I printed and mounted most of these a couple of months ago.  Mounted them maybe 5 days or so after spraying.

My question, has anyone had a similar experience?  Perhaps I should let my canvases 'age' after coating so that all the the shrinkage has occured?

Bill T. if you see this have you noticed this on your MiracleMuck mounting?

Gary

[bill t.]

I have never seen that with the various water based glues I have used, such as Miracle Muck, Franks's Fabric Glue, LaminAll or Lamin-All etc.  I see almost zero dimensional change from the time the image is applied to when the glue is dried, maybe 1/32" shrinkage over a 6 foot dimension.  I use a knife to trim the canvas edges flush with the Gator immediately after mounting, so I'm sure I would have noticed any pulling in from the edges.  I mount my canvas as soon as 8 hours after spraying.

I'm thinking the roller and adhesive combination may be the issue.  Rollers have a tendency to spread the canvas out somewhat.  Of course an adhesive remains flexible for a very long time, so perhaps the canvas is pulling in from the edges over the flexible adhesive as it gradually recovers from the spreading.  You can try using the minimum possible pressure.  Would be interesting to carefully measure the width of the canvas just before and after coating. 

As I found out in years of working on museum displays, adhesives have a slow-motion life all their own.  Adhesive mounted art can glacially slide around on surfaces over very long time scales, especially when mounted vertically.  With glue I expect the canvas to stay locked down in position.  Those and other experiences with undesirable long term effects of adhesives have discouraged from the using them.

After applying my canvases to the glued Gator I usually just bray them down with the cotton-gloved palm of my hand sliding over the surface in various patterns while pressing as hard as I can.  Sometimes I use a fabric covered wood block on the bigger pieces.

[Ken]

Bill -

Some Miracle Muck questions:

• Apparently it can be applied wet, dried and then reactivated with heat. Have you tried that?
• Are you relatively confident that the ingredients are benign to the image and canvas?
• If used on a board less rigid than "Gator", will temp and humidity distort the board or loosen adhesion?

[bill t.]

Miracle Muck in liquid form is not pH neutral, but only weakly so.  It's a water based PVA glue.  I still have mural sized papers prints mounted on Masonite with PVA glue from the mid 70's that show no ill effects attributable to the glue.  So if that double archival whammy of Masonite and non-pH neutral glue have made it this far, I'm pretty confident in the process.  I think the dried glue is not chemically active because of no solvent transport, and it also acts as a barrier to whatever bad stuff might be in the substrate.  You can buy pH neutral Lamin-All or LaminAll from various sources such as Fredrix Canvas and UnitedMfrs.com, those work and smell and handle exactly the same as Miracle Muck.

Yes I have allowed glue to dry and then drymounted paper prints.  Seems to work fine.  One advantage to this process is that you can apply rather thick coats for porous or textured media like canvas and fine art papers which might give you a better contact that just drymount tissue.  You can also reverse the mounting by heating the art package, then immediately peeling off the print.  Have done that also, it works fine.  The biggest disadvantage to drymounting canvas and textured fine arts papers is that it pushes down the surface texture.

I take comfort in knowing that if any of my glued canvases ever starts to peel up or bubble I can probably re-attach it with a dry mount or even on location with a clothes iron or tacking iron.  Never had to do it though.  I have a lot of glue mounted prints out there with zero problems relating to the mounting.  OTOH a large percentage of my early adhesive mounted prints have developed bubbles, oozing at the edges, and de-lamination.  Maybe adhesives have gotten better since then, but I'm not about to bet on it.

The basic reason for using Gator is its remarkable ability to stay flat when something is glued to it.  For instance if you glue a canvas to regular foamcore, the package will deform into a dish shape and stay that way forever.  When you glue to Gator, the package will buckle out towards you for a few hours, then flatten out perfectly.  You can overcome the otherwise permanent warping of foamcore by simultaneously counter-mounting another piece of media to the opposite side, but that's kind of tricky and too time-consuming for my tastes.  My recommendation would have to be for Gator.  But for 1/6 the price at 8 times the weight, Masonite is also worthy of consideration.  FWIW I have no recent experience with mounting to Masonite, so no pointing fingers please.

[Paul2660]

Bill,

Have you ever tried 1/2 foam core with Miracle Muck?  Most often if I am gluing down a 30 x 45 or larger, I move from 3/16" to 1/2 gator, which has gotten very expensive as of late. 
I was curious if 1/2 foam core would work instead it's considerably less in cost and seems to be a good bit stiffer than the standard 3/16 foam coare.  I agree that using wet glue on
3/16 foam core without some form of backing sheet causes way to much buckle.

I also was curious if the 1/2 foam core came in black, since as you pointed out, the black surface makes getting an even gluing much easier, i.e. white on black, instead of white on white.

Thanks
Paul

[enduser]

http://www.3acomposites.com/
http://www.halifaxvogel.com.au/images/documents/Alcan_Full_Range_Display_Brochure_AUG09.pdf

The above two links lead to large range of boards made for display by Alcan and it's new name, 3Acomposites.  US manufacture and sales are found at http://www.graphicdisplayusa.com/

We have had success using "KAPA" board, described on the European site, where we had  3 foot x 2 foot canvas pieces glued using 3M Super 77 that doesn't warp the board after over 3 years now..

Many of these products are easily cut with a Martor Condex cutter and guide rail.  We've discovered that the distributor will cut a 8' x 4' sheet into however many smaller parts for an extra 10% on the price.  Well worth it as you get consistent accuracy in all your pieces.   

A look at Gilman Bros in the US at http://www.gilmanbrothers.com/index.html  might be useful.
I'm not sure how prices compare.

[bill t.]

There are lots of recent options for mounting prints.  I use Gator mainly because it's easy for a single person to cut and handle and very light weight which allows me to make extremely large pieces that do not require elaborate wall mounting.  It's also extremely efficient within a production workflow.  I also frame most of my work, so the substrate is never on view.  It's really a matter of finding the best materials for one's design goals and appearance requirements within the constraints imposed by the available production environment.

Paul, like you I sometimes opt for 1/2" Gator with minimum dimensions starting at about 30".  The reason is not so much for flatness, but for structural reinforcement of the surrounding frame.

Have also experimented with gluing scrap strips of Gator to the back of large 3/16" pieces for extra bracing.  Doesn't seem to cause any warping or localized distortions.  Two or three long, 4 inch wide strips on the horizontal with a few vertical strips greatly increases the rigidity of the board.  Mount the print first, then apply the strips.  I don't have any long term pieces out with that treatment but I suspect it could be pretty stable over time.

[petermarrek]

I commonly use liquid carpenter's glue to mount canvas to 1/8 in. masonite, a bit messy when I run it through my cold laminator. Coat the masonite with glue, postion the print, wrap loosely with kraft paper to take up the excess glue and squish it. Prints made 3-4 years ago and stored in freezing conditions are still fine. After they dry, I coat them with Printshield.