Hot Mounting Tissue issues

[Carnie Bob]

I just switched ( manufacture change) my standard Drytac hot mounting tissue to the new improved Drytac tissue, for the life of me it does not work anywhere near the old product, I am having issues
with it adhering near the edges of a silver print... I do know its really dry in Canada right now and the paper does curl but on the same project same time but new material I have seen dramatic results... Old tissue
works like normal new tissue does not.

Has anyone else seen this issue with the new Drytac material, for what its worth I tried a different product buffermount out of a company in Conneticut with the same results. I have been mounting prints
since 1974 and even in winter with the old stuff so I am now flummoxed.

 

[Erik L]

I’m not sure if this would work for high volume situations but I leave my mounted print in the press till the press has cooled to near room temperature and haven’t had problems but I realize if you need to do many prints it could cause a bottleneck..

 

[DREW WILEY]

I'm surprised a person with all your experience is having this problem. But I'll still explain the relevant workflow for sake of others too. (Actually, I have a little voodoo doll of Bob, and jab it with pins every time he goes to the mounting press.)

The tissue transition has worked so identically for me that I can't even tell the difference functionally. There is a tiny bit of visual difference to the sheets, and of course different labeling. These tissues actually achieve full bond under cooling after being hot pressed. Once I pull the print/tissue/mountboard sandwich out of the press, its's immediately placed under a thick sheet of heavy plate glass for five minutes or so, for sake of the cool-down phase. It has to cool under pressure.

One also needs to be aware of the ambient humidity conditions when doing this kind of work. You want things dry on your work session days, and need to briefly pre-dry both your print just before mounting them together. But that can be overdone, especially on an unexpectedly dry or warm day, or due to too much press "dwell time", especially under such conditions. In other words, if the mount board or print gets pressed for too long, or gets too hot for one reason or another, it's actually counterproductive in terms of successful bonding; hence the potential risk of loose corners or edges.

These Drytac Trimount tissues need to be pressed 190 to 220 F for around 45 seconds; don't overdo it, or the tissue bond might fail at the corners, just like with previous Seal Colormount. (That is the dwell time for my own big 500T press; your own individual prescription might vary from that a little).

One more technicality - once in awhile, some of the silicone from a badly worn out sheet of release paper can actually transfer to the print or board, and inhibit bonding. That's a rare issue; but one should always use new release paper or board if the old sample is beginning to look ratty or splotchy.

 

[rorye]

Drew is your sandwich release paper, print, drymount tissue, matt board?
I've been using 2 ply rag as a top layer and getting a lot of bubbles on the print, perhaps that's my problem?
This has been with D+K tissue, 16"x20" Ilford FB, following time and temperature on spec sheets as well as cool down instructions and overnight pressing with books.
I was thinking of trying MasterMount instead but if the issue is the top board potentially giving inaccurate temperature then I'm thinking user error may be the issue and I'll try with just release paper. My cobcern was the print not liking the 200 degrees.
Forty years in the darkroom and I'm still learning!

 

[DREW WILEY]

I always use 4-ply ragboard - two sheets constituting a sandwich both above and below the print being mounted, along with its own 4-ply mount board. Don't use release paper directly against print paper emulsion! Getting blisters can be a symptom of too much heat. Yes, you need to slightly pre-dry all the pieces of board involved. But if it's exceptionally dry where you are working, or where the board has been stored, the board might be retaining to much heat.

The two sheets comprising the sandwich can be used over and over again until they're simply too dirty. It's a good use for sheets which might have a little corner damage etc, unworthy for actual picture purposes. But after initial pre-drying, you don't want them to retain too much heat during the session. They can cool off a bit in room air while the mounted image is itself cooling down under its glass weight.

Less common is an old press platen which no longer heats evenly; in such a case, having a thicker board between the platen and print is even more important, to help even out any temp discrepancies.

And of course, you might have developed a thermostat issue.

 

[Carnie Bob]

Hi Drew- The tissue of old from Drytac was good to go, the new and improved tissue is less aggressive. In Toronto mid Feb when I has having issues
the overall humidity was extremely low and I was working with oversize (30 x 40inch) silver murals which were curling up even before putting on the tissue. We have had to bring in a humitity control team to actually mist the whole lab top floor and bottom, each 950 square ft. By doing this I think we will be ok, now we have no issues because in Toronto the overall humidity is very high and all paper is lying very flat.
It is an expensive fix but worth it for us, we are experimenting with a new tissue that is apparently much more aggressive but a bit harder to work with, I will report back in late fall our results.

 

[DREW WILEY]

I actually prefer the new tissue, Bob; but it is a little more fussy in terms of correct temp, that I will admit, and needs a little more "dwell time" in the press (about 15 sec more in my experience). I'm in a different climate, of course, where I drymount mainly in the Fall when it's not foggy and damp. And I don't have any dry forced air heating in that building, just electric. But merely operating the 500T press is ample enough heat for that particular room.

I haven't done 30X40 drymounting for a long time; I still have an old 40 inch roll of Seal MT5 tissue laying around; it needed about 250F. In recent decades all my large mounting has been color, cold-mounted involving the roller press.

 

[GregY]

Drew is your sandwich release paper, print, drymount tissue, matt board?
I've been using 2 ply rag as a top layer and getting a lot of bubbles on the print, perhaps that's my problem?
This has been with D+K tissue, 16"x20" Ilford FB, following time and temperature on spec sheets as well as cool down instructions and overnight pressing with books.
I was thinking of trying MasterMount instead but if the issue is the top board potentially giving inaccurate temperature then I'm thinking user error may be the issue and I'll try with just release paper. My cobcern was the print not liking the 200 degrees.
Forty years in the darkroom and I'm still learning!

Rorye, I'm not Drew, but I heat my backing boards in the press.... then use the sandwich. backing board/release paper/print -tissue-mat / backing board. After circa 2 min in the press the print is placed to cool off under a piece of plate glass,

 

[rorye]

Rorye, I'm not Drew, but I heat my backing boards in the press.... then use the sandwich. backing board/release paper/print -tissue-mat / backing board. After circa 2 min in the press the print is placed to cool off under a piece of plate glass,

Hi GregY, that sounds like a great sandwich!
I appreciate everyone's input.

I don't want to hijack OPs thread but did want to mention a great interaction I had re tissue.
I emailed drymounttissue.com with some questions.
The next day I got a call from the owner Thom who spent 20 minutes on the phone giving me advice, not trying to sell me anything, just great old school customer service.
I took his advice (double my press time, add more substrates) and prints are looking great.

 

[DREW WILEY]

My sandwich is 4-ply board on top, against the heated press platen, then the print, then the drymount tissue, then the mounting board, then another 4-ply sheet underneath. Silicone release paper directly against the print emulsion risks some of that transferring into the emulsion itself, irremovably, especially if the release sheet it getting old.

A small strip of release sheet is used briefly in conjunction with the tacking iron to fix the tissue in place on the BACK of the print prior to full attachment.

Otherwise, here's what I do. After pre-drying the various components, I slightly trim the mounting tissue just slightly smaller than the nominal paper size, so that it extends into the borders of the print, but does not overlap.
This is fixed in place to the back of the print with a tacking iron a bit of release sheet near the center of the image.

Then this in turn is put between two sheets of mounting board face down, with an oversized sheet of release paper
between the mounting tissue and the top sandwich board. This is then put under full press pressure just long enough to ensure that tissue fully adheres to the back; with my press, around 30 sec. Let it cool a little and peel away the silicone release sheet from the back of the print.

At that point you can either set it aside for the next phase, or start using your trimmer immediately, to trim away the borders and size it exactly as you wish.

The you position it on your final mount exactly where you want it, and anchor it down with your teflon tacking iron in the middle, but WITHOUT any release paper involved.

Then to your final mounting under pressure and cooling under glass as described at the top.

This procedure is a lot more reliable and efficient than the traditional method of fiddling around with a tacking iron underneath the print, only partially attached from a leading edge.

 

[GregY]

Hi Drew- The tissue of old from Drytac was good to go, the new and improved tissue is less aggressive. In Toronto mid Feb when I has having issues
the overall humidity was extremely low and I was working with oversize (30 x 40inch) silver murals which were curling up even before putting on the tissue. We have had to bring in a humitity control team to actually mist the whole lab top floor and bottom, each 950 square ft. By doing this I think we will be ok, now we have no issues because in Toronto the overall humidity is very high and all paper is lying very flat.
It is an expensive fix but worth it for us, we are experimenting with a new tissue that is apparently much more aggressive but a bit harder to work with, I will report back in late fall our results.

Bob could you please weigh in on your method.... use of release paper?

 

[cliveh]

Why not use self adhesive foamboard? Easy to use, no heating involved, various different weights of foamboard available, easy and light to handle for exhibition.

 

[GregY]

Why not use self adhesive foamboard? Easy to use, no heating involved, various different weights of foamboard available, easy and light to handle for exhibition.

Clive, I don't use it for the same reason I choose not to use RC paper.
Over time i've built up my darkroom to where I have several enlargers and two dry mount presses.
It's a personal preference for traditional archival materials.

 

[David R Williams]

There's much information here that would be very helpful, but which might not be seen by many with this thread being posted under the Product Availability board.

Moderators: Could this thread be copied to, or at least the relevant posts dealing with mounting techniques be re-posted to, an applicable Darkroom board??

 

[DREW WILEY]

First of all, typical self-adhesive foamboard lends a cheap look. If it's low-tack, and repositionable, it's not reliable over the long run; and if its high-tack, there is zero room for error. it's also unacceptably thick for stacked storage.

I do use permanent acrylic foils for large RC and polyester color prints, along with a dedicated roller press. It's not a forgiving procedure at all; and one needs a very smooth substrate for glossy media, or else you get a visible "orangepeel" effect. In other words, this is not art store material, but a professional category of product, generally sold in volume.

For actual paper media, like FB b&w paper itself, I prefer drymounting on a high quality 4-ply ragboard. Rising is my favorite brand. What Archival Methods sells as pre-cut sheets appears to be the same thing.

 

[MattKing]

There's much information here that would be very helpful, but which might not be seen by many with this thread being posted under the Product Availability board.

Moderators: Could this thread be copied to, or at least the relevant posts dealing with mounting techniques be re-posted to, an applicable Darkroom board??

@David R Williams and @Carnie Bob ,
Actually, the Presentation and Marketing sub-forum is specifically designed to deal with mounting techniques, and it has the added advantage of being available to those who have interest in mounting non-darkroom prints, so I've moved it there.

 

[David R Williams]

Perfect - thanks Matt.