Dry Mount Procedure

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Just received a used Seal Junior 70 and can't wait to use it. Since it doesn't come with a manual, I would appreciate anyone kind enough to brief me on the proper mounting procedure. I would be using the Seal ArchivalMount tissues to mount fibre-base B/W photographs. Questions:- 1. Do I apply hand pressure to the print/mounting board during mounting? 2. Do I need to sandwich the print/mounting board between two sheets of mounting board? 3. What's a release paper used for? 4. How long do I leave the print/board in the press? 5. What's the ideal temperature setting? 6. Do I place the print facing up or down?

Thank you for taking the time to help out.


-- Aaron (ngaaron@singnet.com.sg), September 06, 2001


When you buy the dry mounting tissue (I use Seal MT5 for black & white fiber prints), there will be some instructions that will indicate temperature recommendations. The whole process is a little tricky at first. I use a couple of pieces of 2-ply rag board as the protective layers above and beneath the print. I first tack the tissue onto the untrimmed print at the center with a tacking iron. I then trim the print so the tissue and image area will exactly the same size. I next, place the the print on the mount board (4-ply rag board) and carefully tack the tissue to that at two adjacent corners, pulling gently out from the the center of the print so I don't get buckles. I then place the whole mess between the two protection sheets I described earlier and close the press. No need to hang on to the handle, as the thickness of all the materials will take care of the required pressure. Now here's the trick: If it's too hot or you cook it for too long, the edges will lift up. If it's too cool or you don't cook long enough, the whole print may come loose. When you remove the mounted print, quickly place it under a clean, flat weight, prefereable something metal that will act as a heat sink. This will assure that the mounted print will cool into a flat state and that portions of it won't lift up from the mount. Hope this helps.

-- Robert A. Zeichner (info@razeichner.com), September 06, 2001.

Ansel Adam's Book "The Print" shows how to do this. Great resource for print making.

-- Gene Crumpler (hassieguy@att.net), September 06, 2001.

Release paper is placed on top of the print to protect it during the dry mounting process. Light Impressions sells something else that serves the same purpose and is more permanent than release paper (i.e. it can be used over and over). However, if you need to make more than one pass (i.e. if your print is larger than your platen so that you first dry mount say the top half of the print, then repeat to dry mount the bottom half) I'd suggest placing a piece of mat board on top of the print rather than release paper or the stuff that Light Impressions sells. If you use something thin like release paper then the edge of platen leaves a mark on the print at the point where the second run was made (at least mine does). The termperature needs to be turned up to something like 300 or 350 if you use mat board on top of the paper or else it will take forever to melt the tissue. If you have access to back issues of the magazine "Photo Techniques," I believe there was an article on dry mounting within the last year or so. You probably could get a manual from Seal also or check out a book from your local library. One dry mount press is pretty much like another so you shouldn't need anything specific to your particular brand and model.

-- Brian Ellis (bellis60@earthlink.net), September 06, 2001.

i would just comment that the library of congress does not consider any method of dry mounting to be archival. all of the materials which we prepare for exhibition purposes for HABS/HAER are mounted with linen tape hinges. prints are flattened prior to mounting using mild heat in a press.

-- jnorman (jnorman@teleport.com), September 06, 2001.

I would strongly caution against the 300-350 degrees Brian suggests. I find if I use smooth (must be smooth!) crescent board on top, 180 degrees is enough (with Seal ArchivalMount tissue). For me, any hotter and the print sticks slightly to the board and you can sometimes see where that happened. Granted, the thermostats on these things are probably inaccurate from the get-go, and the tissue melting points vary depending on the type, so what you have to do is test your materials with your press --- don't start with a high temperature on a good print! Practice with reject prints and scrap board. Also, the pressure is important --- if you really have no manual or the Seal website doesn't help, you can vary pressure by adding cardboards under the print. For best adhesion you must pre-dry all materials to get the humidity out, in press without the tissue, first.

-- Sandy Sorlien (sand44@mindspring.com), September 06, 2001.

Aaron... practice on unwanted prints... my experience...time to time... fiber base paper do wrinkle no matter how careful you dry mount it...after a couple of bad luck... I give up dry mount... I solve the problem by printing on over size paper... (one size over size of the print) and reinforce the back of the frame... the print will look and stay flat... good luck....

-- dan n. (dan@egmail.com), September 06, 2001.

jnorman: same thing in the museum community in regards to dry mounting...to permanently mount anything is considered to be a big mistake, on par with ruining it. The hallmark of being "archival" is to be reversible.

-- DK Thompson (kthompson@moh.dcr.state.nc.us), September 06, 2001.

I don't think it is fair to compare the mounting policy of a museum or the Library of Congress with what photographers should do to their own photos. In the mounting process (and the washing, toning, drying, spotting, etc) a certain number of prints of will inevitably be damaged. That is why photographers need to make extra prints to account for these problems. However, once processed and properly mounted, the print will look better and will be considered archival. For a museum, there is only one print, and they cannot risk damaging it with the dry mount process.

-- Michael Feldman (mfeldman@qwest.net), September 06, 2001.

Hey...you all can do whatever you want...really. It's just that technically the words "archival" and "permanently mounted" do not work together.

Have you ever wondered about the lack of any accelerated testing, or even "real-time" testing, done to dry mount adhesives as well? Why bother with acid-free board and all that, if you're unsure just what the adhesive and even the base material of the tissue itself is made of?? Just something to think about.

-- DK Thompson (kthompson@moh.dcr.state.nc.us), September 06, 2001.


Thanks for all the useful tips. They'll come in handy when I get started. A couple more questions if you don't mind:- 1. Does it mean that release paper isn't really necessary? It looks quite expensive and I'll rather skip this one if I can. 2. The press is in 110v and I'm in a country that requires 230v. I've found an old transformer that reads 330 VA. What does 330 VA mean? Is it useable for my mounting press that says 3.5 amps, 450 watts? Am I going to blow it??? 3. There's also a red indicator on the press. Is there other meaning to it other that to show that it powers up?

Thanks again for helping out.


-- Aaron (ngaaron@singnet.com.sg), September 07, 2001.

Any completely smooth paper or board can be used as a release paper. Vellum is great, but that is expensive. I just use Crescent board now, no paper, with Agfa Classic fiber prints. And regarding permanent/ archival issues, I suggest only drymounting for exhibition, and only if absolutely necessary to keep print flat (fiber *will* lie flat, flatten it by itself first). Do not drymount what you intend to sell or donate to a museum or discerning collector. Cheers, Sandy

-- Sandy Sorlien (sand44@mindspring.com), September 07, 2001.

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