heat activated foamboard

margaret b

Grumbler in Training
Jan 12, 2005
Hello from a long-time lurker who is going nuts.

I just got my latest shipment of heat-activated board from Decor, and they apparantly have changed suppliers. The old stuff was Foam-x and the new stuff is fome-cor.

I use a Seal 500 press with release board. If the press is hot enough to mount properly, it melts the exposed glue all over the release board. If you cool it down enough not to goop everything up, the bond isn't good enough/bubbles. Does anyone have any suggestions, or do I have to ship 7 cases of foam back to New York!!! I had this same problem with Crescent heat-activated from a local supplier.

At least maybe someone out there will have a suggestion for a less tempermental product.

Thanks a bunch!
Margaret... I've not had any trouble with Fome-Cor, myself. Are you using the release paper that comes in the box, in-between each board? They should keep your release board nice and clean. The glue on the exposed part of the board does melt, but I've been able to use those scraps again on other projects without any trouble. Or cut the board closer to the image size before mounting, so your usuable scrap with be "virgin" for the next small project.

I use the same Heat Activated board and always use the supplied relese paper when I mount. I throw it out as I use it to avoid making a mess.

Also, I don't think this kind of product is intended to be used with exposed adhesive (except for very small amounts). It is best when used by cutting the foam to size first then mounting only items the same size as the board.

That's how we use it and we sell a ton of it.
I use Bainbridge Speedmount for all dry mount projects and have no trouble with exposed adherent. We cut our boards two inches bigger than the frame size and cut down after the mount is completed. The dwell time is less on Speedmount than other dry mount boards.
I've had the best success with the Bienfang product, though you still need to keep an eye on the release board for stray adhesive.

I don't remember what it's called. It might be Single-Step. Actually, it's probably not Bienfang any more.

Hunt/Seal/Bienfang/Toyota, maybe?

Some of the heat-activated fome boards are truly awful. I tried one with adhesive that soaked through a heavy, coated poster and stained the front. Then the bond released. Mostly.

The old Foam-x had tissue that was shipped between the boards that was just thrown out. I thought that the paper in the box was just trash!

Now it works great!

. . . although a call to Decor asking why they switched brands without telling me or instructing me about the differences might be in order . . .
Lots of friendly replies, but I don't think anyone included the reminder that drymounts must be cooled under weight.

If you take the dry mount "package" out of the press and put it under weight immediately -- release paper/board and all -- then when it's cooled, the release paper/board will peel right off. I've used several brands of pre-adhesive board, and they all work that way.

And if you don't cool under weight, the gooey, melted adhesive would be running all over the place.

NO drymount is dependably bonded if not cooled under weight. Y'see, the bonding happens as the melted adhesive cools and solidifies. Cooling takes longer with a release board than with a release paper, because the board thickness holds more heat.
Thanks for that question. Being a non-professional, can someone tell me if I am doing something wrong?

I use SingleStep and I have been discarding the tissue that seperates the foam board. Then I cut the board to just about the exact size of the print. I then place the print on the foam board and use a thinner "greenish" board to place on the print for protection. Then I use my heat press to heat the item (30-60 seconds). I have not had a problem except in the summer, when it seems to bubble sometimes. I attribute this to working in my basement (humidity).

However, I am looking to save money and so I contacted Decor. They told me that their Heat Activated Board, which I guess is foam-cor, will do the same job, and with the sale they have this month it's greater than 50% cheaper.

My question is, is it just as good? More problems? And have I been doing it wrong to begin with? Will there be additional steps if I go with Foam-Cor?

I have found the several brands I've tried work about the same. I have used the Bienfang and the International Paper. I "stuck" with the IP because of my supplier, I like the release paper they put between each sheet in the case, and I pay about $4.75 per 40 x 60 sheet.
kbarrett, don't commit to a large quantity of a different brand without an opportunity to try it out first. They are NOT all the same.

The white tissue that interleaves the Single-Step is, I believe, just that: interleaves. As always, I could be wrong, though I think I actually read the instructions years ago.

I use the Seal release paper, above and below the mounting package, and a release board (though it's not in contact with the adhesive at all) above the package. I nearly always leave a margin of board around the print because my Vacuseal press will compress the edges of the fomeboard. I trim it after the mounting has cooled.

I use a temp of about 190 degrees and a dwell time in the Vacuseal of four minutes and, I will confess, I do NOT cool the package under weight. To my knowledge, none of the first 12,000 or so items mounted this way have released but, I suppose, there's always a first time.
There are three common causes of bubble & weak mounts:
1. Failure to cool under weight.
2. Failure to pre-dry in a mechnical press.
3. Inadequate time, pressure, or temperature.

Drymounting is generally done in an "assembly", which includes (from the top down):
A. Release paper/board
B. Art paper
C. Drymount film/tissue
D. Mount board

When heated, all parts of the assembly expand at different rates, and the adhesive activates (liquifies, or gets gooey).

When the dry mount assembly is removed from the heated press, it immediately begins to cool, and all of the materials contract at different rates.

If the art paper or the dry mount tissue cockles as it cools & contracts, or if the mount board warps a bit -- even temporarily -- the mount will be weakened, and may bubble in some places.

Another common cause of bubbles is failure to pre-dry all parts (except the adhesive, of course) by heating them for a minute or two before mounting. This pre-drying removes the moisture which soaks into the hygroscopic materials from ambient air. It is especially important in high humidity environments.

Exception: Pre-drying is not necessary when using a heated vacuum press, as the vacuum dehimidifies the assembly as it is heated.

In a nutshell, the dry mount process involves 4 factors: temperature, pressure, time, and moisture. If any of these is out of balance, the mount will be weakened. And the balance is not always the same. For example, various adhesives activate at different temperatures. If a release board is used, it will require more time for the heat to penetrate, than if release paper is used.
"Y'see, the bonding happens as the melted adhesive cools and solidifies."


I understood this was not the case - Most modern drymounting tissues use a polymer that has a molecular change as the heat rises which causes the bond. It doesn't bond as it cools - that's why it's not revesable by reheating.

I do highly recommend cooling under weight.
Originally posted by John Gornall:
...Most modern drymounting tissues use a polymer that has a molecular change as the heat rises which causes the bond. It doesn't bond as it cools - that's why it's not revesable by reheating.
If that's true, I thank you for the correction.

My understanding is that there is a molecular change which, as you said, prevents re-activating the "thermosetting" polymer adhesives, and that "thermoplastic" adhesives are the ones that may be re-activated. But I was told they all bond during cooling.

If the bond occurs when the adhesive is heated, then cooling under weight would be unnecessary. Why do the makers ALL continue to recommend cooling under weight?

a line from the Drytac website:

"The pH-neutral heat-activated adhesive will bond at temperatures as low as 185°F (85°C)."

When heated the art, tissue, and mount board expand at different rates - they also contract at different rates as they cool. None of the 3 are strong materials and by holding them flat while cooling they can be restrained and therefore when they all reach room temperature the package is more likely to be flat.
I used fushion 4000 for years on acid free 1/8 inch foam and mounted at approx 190 degrees for 45-60 seconds with release paper, stood them on end to cool and had great results. I did the same thing with the Miller thermo foam board.

When I mounted to mat board I always did the pre-dry, heat preassure and under weight to cool.
Nothing like a good piece of plate glass. I say when, because I do as little as possible these days. My old seal press has seen better days. The pressure adjustment on the press is also important.

Any and all of the above procedures come with no guarantees and not necessarily recommend by the author.
My supplier has Speedmount and Fome-Cor anybody have a preference? Question also about temp and time for my VacuSeal 3646M-HS machine.
Speedmount 160 degrees or below depending upon what you're mounting. 30 seconds dwell once you've got vacuum. Specs for speedmount will let you go down to 150 degees. Temps above 170 will cause problems.

Similar temps and dwell for A/C Restore

These comments should be tempered with the note that I have never had a piece of heatactivated fomecore in my hands for testing or use. It's just not available to me and I haven't a clue as to its specs. I don't believe they have a representative on the FACTS Tapes and Adhesives committee either.
Lots of friendly replies, but I don't think anyone included the reminder that drymounts must be cooled under weight.
I always cool under sheets of heavy 1/4" glass but have never seen anything on how long they should remain under weight. I've been leaving them an hour or so. Should they be kept under weight just until they cool or longer????
How long?????????
ArtCare Restore is a new Bainbridge mounting product that's getting a lot of attention. I haven't used it, but it is apparently reversible, at least to some extent.

Do a search on this forum and you'll find some extensive discussion about the product.

Here's one of the discussions and it contains a link to yet another. Open them all simultaneously to see how many windows your system can have open without crashing.