Adhesive for attaching large prints to Gatorboard

[pcgpcg]

I’m mounting three large format B&W prints on ½” black Gatorboard. I’ve already purchased the 4’ x 8’ sheets of Gatorboard and the prints are being ordered from a low-ball online poster printing outfit on 250 gsm matte photo paper. Sizes range from 15 to 24 square feet and I do not need archival mounting. There will be no frame. I plan on gluing wooden blocks to the back of the Gatorboard to float the prints 3/4" off the wall.

I’ve looked at various spray adhesives available locally and most say that for larger than 12” x 12” I should spray both surfaces, then wait two minutes before contact and no longer than five minutes. I’m thinking that by the time I’ve sprayed both surfaces outside (for ventilation) then brought them into my shop to attach them, five minutes might have passed.

I’ve looked at spray adhesives from 3M and Krylon (three different variants from them) and I’d appreciate advice on what adhesive to use, and tips on how to apply it and then manage the process of maneuvering the print onto the Gatorboard.  I have a large cabinet saw and table for trimming. I have experience applying laminates to plywood sheets and have a hand roller I can use to apply moderate pressure. I'm aware that too much pressure will damage the Gatorboard. My biggest concern is how to manage positioning before contact. For applying laminates to plywood I've used 1/2" wooden dowels to keep the substrates separate.

Also… any recommendations for sealing afterwards?

Thank you!

[Deardorff]

Look at Scotch PMA, Positionable Mounting Adhesive.

It works and allows time to reposition artwork before using pressure plate to set the adhesive.

You get it, cut to size and layer if not big enough. Then peel off the protective covering, put the print on the adhesive, place the protective covering over the print and press the print to the adhesive using the supplied hand holdable tool.

You can learn on smaller prints. Useful stuff for quick and easy mounting.

Or, the cold mounting adhesive below may solve your problem. Easy to use and in sheets of various sizes which can make working with it easier.

http://www.artgrafix.net/store/page45.html

[stockjock]

I have to respectfully disagree with Deardorff.  I have had terrible luck with the Scotch Positionable Mounting Adhesive.  Essentially that stuff is sort of like the spray adhesives presprayed onto a release liner so the idea is you can cut a sheet of the PMA and put it onto the back of your print or board and by rubbing it transfer the adhesive to that substrate and then pull off the release liner and then adhere the print or board to whatever you applied the adhesive to.  It sounds great but in practice it works poorly.  The adhesive isn't 1) sticky enough and 2) sufficiently film like, to transfer evenly onto the first thing you are applying it to.  Consequently you get patchy applications of the adhesive and these sorts of rubber cement like strings that form.  I think it is terrible stuff but I guess others have had better luck.

The sprays are just plain messy and it is difficult to work with large sprayed sticky surfaces in general.  Also, it can be difficult to apply them evenly and I've had problems with bubbling on larger prints.  I do think they would work for your application once you get the hang of it but I imagine trying to position two large, sticky surfaces would be challenging.

What has worked with me is Gatorboard or Sintra with an adhesive film preapplied.  Those are very easy to work with in smaller sizes, i.e. <24" wide and especially with a cheap cold laminator.  It sounds like that won't quite be suited to your application so I would investigate using something like the Drytac MultiTac White Double-Sided Mounting Adhesives that are available up to 61" wide.  I think they should work about as well as gator with a preapplied adhesive layer.  You can buy them here in a variety of widths: https://www.mybinding.com/multitac-white-double-sided-mounting-adhesive.html.  You should watch a couple of youtube videos before you try this but it is really pretty easy.

Another option, but I have no idea how well it works on paper, is a brush on glue like Miracle Muck.  I've never used it and I don't know the best place to buy it but you see a lot of people working with canvas recommend it.

[mkihne]

If archival is not a concern(or even if it is) why not buy a gallon of Elmer’s glue at your local hardware store and apply it with regular paint rollers with appropriate knap or foam rollers.  Elmer’s may be as archival, or nearly so, as Miracle Muck or other similar products. The key is working quickly in getting the glue down with complete coverage, about 5 minutes. I can do up to a 20x30in. with a 4 in. throwaway foam roller mounting canvas to gator. The key is accurate positioning from the get go, as repositioning is nearly impossible. It may work to apply like vinyl graphics, lifting one side of of the print and rolling the other side, flatten, smooth, lift the other side and repeat. An extra pair of hands or two might be helpful if you can get them all on the same page.

Mike

[patjoja]

I’m mounting three large format B&W prints on ½” black Gatorboard. I’ve already purchased the 4’ x 8’ sheets of Gatorboard and the prints are being ordered from a low-ball online poster printing outfit on 250 gsm matte photo paper. Sizes range from 15 to 24 square feet and I do not need archival mounting. There will be no frame. I plan on gluing wooden blocks to the back of the Gatorboard to float the prints 3/4" off the wall.

I’ve looked at various spray adhesives available locally and most say that for larger than 12” x 12” I should spray both surfaces, then wait two minutes before contact and no longer than five minutes. I’m thinking that by the time I’ve sprayed both surfaces outside (for ventilation) then brought them into my shop to attach them, five minutes might have passed.

I’ve looked at spray adhesives from 3M and Krylon (three different variants from them) and I’d appreciate advice on what adhesive to use, and tips on how to apply it and then manage the process of maneuvering the print onto the Gatorboard.  I have a large cabinet saw and table for trimming. I have experience applying laminates to plywood sheets and have a hand roller I can use to apply moderate pressure. I'm aware that too much pressure will damage the Gatorboard. My biggest concern is how to manage positioning before contact. For applying laminates to plywood I've used 1/2" wooden dowels to keep the substrates separate.

Also… any recommendations for sealing afterwards?

Thank you!

See this video for some suggestions on possible positioning solutions: https://robertrodriguezjr.com/2014/12/10/video-tutorial-mounting-prints-onto-gatorfoam-board/

I normally use self-adhesive Gatorfoam, but the largest I've done is 24x36.  I use Rodriquez's technique except I found that cutting the release liner creates a line in the print underneath, so I fold the liner back rather than cut it.

In your case, since you already have non-adhesive Gatorfoam, I think you can use a similar technique but you'll have to apply the adhesive in sections.  Holding the print down with paper weights, position the print on the gatorfoam without the adhesive.  Move the print weights to one end and roll the print back exposing the gatorfoam. Apply a narrow strip of adhesive to the opposite end, roll the print back and position that end down.  Then remove the weights on the non-glued end, place them on the glued end and roll the print back the other way.  Then you can begin to lay adhesive down in sections, gradually rolling the print all the way back down.  Since you're working with such large prints, it may help to have a friend.

Doing it this way takes some of the worry out of it and you can proceed slowly to make sure the print is laid out smoothly.

Hope this helps.

Patrick

[Frodo]

I've had good success with Scotch PMA up to 13 x 24 inch on MDF.
It is quite expensive, at least here in New Zealand - similar to price of same size fine art paper.

[Simon J.A. Simpson]

I recommend that you do not use 3M/Scotch photo spray-mount adhesives.  I used them to mount an exhibition on foam core board and most of my prints fell off the wall.

Long story short.  After a dialogue with 3M in the UK (who were very helpful) it transpires that something in the chemistry of the foam core board reacts with the adhesive to deprecate its effectiveness.  This is exacerbated by heat and humidity (the exhibition was in Turkey).  3M recommended using their spray adhesive intended for carpets !

[framah]

PMA is useless for anything over about 24" square.  3M will tell you that there is a limit to the shear strength of their product and their answer is about what i just typed.


Call them if you want the official response.  At the size you are working with, there is NO WAY PMA would hold.

As the paper and the gatorbord want to expand and contract, the adhesive is trying to keep its hold and the shear strength won't be able to overcome the movement of the paper and the gatorboard.... thus you get bubbles/areas of failure.

I second the idea of Miracle muck as I have heard many framers use it. I have a 40x60 heat press so i use a more permanent tissue/adhesive layer to mount it permanently. 

I don't think you will get a clean of cut on a table saw as you can with making multiple cuts with a utility knife. I mount to 1/2" Gtbd all the time and that is how I cut it. I also then take a sheetrock sander and clean the back edge of those sharp pieces that happen as you break the extra off. Just a good thing to sand the edge smooth and clean.


So... PMA useless... Miracle muck good. 

PS: I have been doing framing for 25 years so I think I have a pretty good handle on this.

[BrianBeauban]

PMA is useless for anything over about 24" square.  3M will tell you that there is a limit to the shear strength of their product and their answer is about what i just typed.


Call them if you want the official response.  At the size you are working with, there is NO WAY PMA would hold.

As the paper and the gatorbord want to expand and contract, the adhesive is trying to keep its hold and the shear strength won't be able to overcome the movement of the paper and the gatorboard.... thus you get bubbles/areas of failure.

I second the idea of Miracle muck as I have heard many framers use it. I have a 40x60 heat press so i use a more permanent tissue/adhesive layer to mount it permanently. 

I don't think you will get a clean of cut on a table saw as you can with making multiple cuts with a utility knife. I mount to 1/2" Gtbd all the time and that is how I cut it. I also then take a sheetrock sander and clean the back edge of those sharp pieces that happen as you break the extra off. Just a good thing to sand the edge smooth and clean.


So... PMA useless... Miracle muck good. 

PS: I have been doing framing for 25 years so I think I have a pretty good handle on this.

I'm sorry but I disagree. PMA is not useless and the shear strength is more than adequate for this application ( Disclaimer: I have no association with 3M, their subsidiaries, etc.). 3M wants to play it safe and I can't say I blame them. Gator foam can bow with temperature changes but does not expand or contract enough to present a problem. That bowing however, can cause a problem and it has more to do with humidity changes. I have prints I mounted that are 4'x8' using various PSA adhesives over 30 years and they are just as good as the day they were first mounted. The technique given in the previously recommended video,  https://robertrodriguezjr.com/2014/12/10/video-tutorial-mounting-prints-onto-gatorfoam-board/, works just fine, especially if you don't have money lying around to invest in specialized equipment. I have hand applied and mounted prints as large as 50" x 144" using his the technique on that video, with a few variations, but in general it's close enough. The only thing I'd steer clear of is the spray adhesives, even if you follow the directions closely your results can vary and I have seen countless failures with them. The stability and compatibility of the components is key to success.
Unless you have a laminator to apply the adhesive I'd recommend you find either the adhesive coated boards or find a local sign shop, photo image provider, or reprographer who has one and have them apply the adhesive to the substrate. Especially if you only need to mount a few prints. These adhesives are sold in rolls in most cases and roll lengths vary from 30' to 300' (or more). That can be quite expensive if you need only mount 3 or 4 prints. But, for the price of that package of 25 sheets of 32" x 40" adhesive @ $249.00, you can buy a full roll of 38" x 150' for $214.64 from AGL Inc. (Disclaimer: I do work for AGL Inc.) that will allow you to mount 45 prints that are 32" x 40".
I have worked as a mounting and framing technician for professional custom photo labs in Chicago for 19 years ( PSA mounting, laminating, dry mounting, second surface acrylic mounting, custom framing and matting, image transfers to canvas and vinyl, exhibit and display building, etc.) and have been selling laminating, dry-mounting, liquid laminating and coating supplies and equipment for the past 14 years. I am a trainer and experienced installer. There are many methods people use to achieve the end result. If they are happy with the result I would not stand in their way. But if they are having difficulty I'm here to help.

[mkihne]

PMA is useless for anything over about 24" square.  3M will tell you that there is a limit to the shear strength of their product and their answer is about what i just typed.


Call them if you want the official response.  At the size you are working with, there is NO WAY PMA would hold.

As the paper and the gatorbord want to expand and contract, the adhesive is trying to keep its hold and the shear strength won't be able to overcome the movement of the paper and the gatorboard.... thus you get bubbles/areas of failure.

I second the idea of Miracle muck as I have heard many framers use it. I have a 40x60 heat press so i use a more permanent tissue/adhesive layer to mount it permanently. 

I don't think you will get a clean of cut on a table saw as you can with making multiple cuts with a utility knife. I mount to 1/2" Gtbd all the time and that is how I cut it. I also then take a sheetrock sander and clean the back edge of those sharp pieces that happen as you break the extra off. Just a good thing to sand the edge smooth and clean.


So... PMA useless... Miracle muck good. 

PS: I have been doing framing for 25 years so I think I have a pretty good handle on this.

Framah, your post reminded me of a mention elsewhere that miracle muck can be heat activated. This should allow you to coat gator, let it dry and heat activate it after easily positioning the artwork. This is unlikely to help the OP but wondering if you have tried it? Again, Elmer’s glue on basswood panels for some canvas and over sprayed(desert varnish) matte paper images show no visible abnormality after three years for me. For sale panels, I use miracle muck, but they don’t ship during low temperature weather, so I have to stock up pre winter.

[stockjock]

These adhesives are sold in rolls in most cases and roll lengths vary from 30' to 300' (or more). That can be quite expensive if you need only mount 3 or 4 prints. But, for the price of that package of 25 sheets of 32" x 40" adhesive @ $249.00, you can buy a full roll of 38" x 150' for $214.64 from AGL Inc. (Disclaimer: I do work for AGL Inc.) that will allow you to mount 45 prints that are 32" x 40".

Are the AGL adhesives only available directly from AGL and how do you think they differ from the DryTac adhesives?

[mearussi]

It's interesting the wide variety of comments here.

I've experimented with spray, Scotch PMA and glue and because of the large sizes you're wanting to mount I would recommend glue as the most forgiving and easiest to work with. Using both spray and PMA (a misnomer in actuality as it's barely repositionable) you just cannot make a mistake as correcting it is almost impossible, but with glue you have time to slide your print around to get it aligned exactly where you want it (just make sure you don't get ANY glue on your print as removing it is almost impossible without ruining the print).

To use glue correctly you have to apply pressure on top of it (preferably using a hand roller of some sort) after you've got the picture positioned where you want it in order to even out the glue, because if you don't you'll have an uneven surface. Put a sheet of butcher paper on top of your print that's larger than the print as the glue will squeegee out beyond the edges of the print. For this reason also make sure your print is larger than the mounting board so the edges with the excess glue on them can be trimmed off.

[patjoja]

All the above issues are why I use self-adhesive Gatorfoam... Just sayin'

Patrick

[BrianBeauban]

All the above issues are why I use self-adhesive Gatorfoam... Just sayin'

Patrick

Hands down the easiest solution in this case.

[BrianBeauban]

Are the AGL adhesives only available directly from AGL and how do you think they differ from the DryTac adhesives?

Both companies offer a variety of adhesives for different applications. For the needs expressed in this situation a good solvent acrylic or aqueous acrylic adhesive will work just fine. I prefer not to get into the differences between these two companies because I used to work for Drytac and I currently work for AGL, so my opinion can be biased. And yes, AGL only sells direct.

[Stephen Ray]

Unless you have a laminator to apply the adhesive I'd recommend you find either the adhesive coated boards or find a local sign shop, photo image provider, or reprographer who has one and have them apply the adhesive to the substrate.

This ^^^^
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If the print can be touched by people or things, you should have it professionally mounted to 1 or 2 inch gatorfoam at a large format print provider or sign shop in your area. The print should also be laminated but your print paper(?) may not be receptive to that.

If the print will definitely not be touched, you can just gallery-wrap the paper print around 1x2 inch lumber with staples.

Both of these methods are successfully used all the time.

Good luck.

Good luck. Again. And your 1/2" Gator will bow if it isn't already. And your blocks won't work over time. And you now will need full-length supports.

[BrianBeauban]

On larger pieces we would build either a back-frame inset about 2" around the perimeter or an H-hanger, similar idea but less wood. Generally 1/2" gator would warp on any size over 30" x 40" and 3/16" gator larger than 24" x 36". The larger pieces I still have incorporate back-frames. I would show pictures but they're way up high on a wall and difficult to get to.

[pcgpcg]

Thank you so much to everyone who offered suggestions on how to mount large format prints on ½” Gator Board. I thought I should provide an update on what I ended up doing and how it has turned out. The prints have been hanging for four years now and there has been no delamination.

After carefully considering everyone’s comments, here’s what I did:

I used the Lightroom export feature to size my prints to their final physical size in inches, 150 dpi, and sharpening for matte paper. I ordered low-cost prints from www.posterprintshop.com, and specified matte finish and a 2” border, as I wanted room for error.

I purchased three sheets of ½”x4’x8’ black Gatorboard locally. I cut each sheet an inch larger in each dimension than the print w/borders. Again, not ever having done this, I wanted room for error, and that was cheap.

I was unable to find Gatorboard with adhesive available locally and the cost of shipping was prohibitive. So I purchased a 24” x 50’ roll of 3M568 Mounting Adhesive from Uline and had it shipped.

Mounting Procedure:

1) I prepared each print by unrolling it and letting it lie flat for a day. Then I rolled it up on a cardboard tube (I covered the outside of the tube with clean draft paper first to keep the print clean) with a strip of 24” wide draft paper lying in the middle on the face of the print, to protect the print when I unrolled it and pressed it into the Gatorboard. I rolled the print in the opposite direction from how I received it. This means the print face was facing inside the roll, and would allow me to unroll it face up.

2) I then mounted the adhesive paper to the Gatorboard. This paper comes with protective paper on one side and the other side is slightly sticky. All of my prints were larger than 24” in the smallest dimension so it was necessary to lay down two strips of adhesive paper sided by side to cover the Gatorboard. I was greatly relieved to find that it was easier than I had feared to line the strips up so that there would be virtually no seam showing. I laid the slightly sticky side down, aligned the two strips, then used the provided plastic squeegee to press the paper firmly onto the Gatorboard, and finally used a razor blade to trim off the extra adhesive paper.

3) After all the paper was stuck to the Gatorboard, I proceeded to peel back the protective paper to expose the adhesive and discovered immediately that I needed to re-squeegee the paper so that the adhesive didn’t come up with the protective paper when I tried to pull it off. Doing that and pulling very slowly I was able to get it all off without any problems.

4) The next step required two helpers, one on either side of my work table, to hold the roll above the Gatorboard and slowly unroll it while I pressed the middle of the unrolling print onto the Gatorboard with my gloved hands. Since it was rolled up with some draft paper I was free to slide my hands around to ensure that it went down smoothly with no bubbles, etc. We unrolled about a foot of each print first, holding it away from the Gatorboard, so that I could do my best to align it properly before pressing it down, so it wouldn’t go off to one side as we unrolled it. Again, this was easier than I had feared. With the oversize Gatorboard and 2” margins I had plenty of room for slop, but ended up being off only about 1/8” over five feet. I think I was lucky and normally one should expect to be off more than that.

5) I then went over the whole print with a laminate roller, working from the center out. Someone had commented to be careful not to press too hard and dimple the Gatorboard. Well I did on my first print. Fortunately it is a small area and the print is mounted in a dimly lit room and is not noticeable. If you do this practice on some scrap Gatorboard first so you know what it takes to dimple it.

6) Next was trimming. I have a woodshop with a cabinet saw so this was easy. A high quality carbide blade went through the Gatorboard and paper like butter and left a very clean edge.

7) I didn’t varnish or otherwise protect the prints, primarily because I have no experience with this and didn’t want to ruin what was a good result so far. The prints are mounted in a high-end restaurant and I don’t expect that there will be much of a problem with people touching them.

8 ) To address concerns about future warpage I decided to use the walls to hold the prints flat. I had a supply of aluminum French cleat material on hand so I epoxied a series of small cleats to the back of each print – on all sides and in the middle. I made a jig that registers to the edge of a print so I could install the cleats precisely and in a repeatable fashion. I then used a laser level on a tripod to mount the mating strips to the wall. I worked slowly and carefully and it took a little less than an hour to mount each print to the wall. The cleats hold the Gatorboard about a quarter inch off the wall.

Basically the entire process was easier than I’d expected and everything turned out well. I want to emphasize that your responses to my post are what enable me to get this project done. Note that what I ended up doing was quite different from my original plan. Your willingness to take some time to contribute to the forum enabled me to formulate a mounting plan that was affordable, relatively easy, and worked out well. Thank you!