Drymounting problems

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My drymounted black and white prints often have the slightest upward curl at the edges. While not large, this defect is distracting. This happens with Seal MT5, Seal Colormount, Seal Archival, and Saunders drymounting tissue for times between 15 sec and 2min. Predrying the prints and museum board, as well as allowing the mounted prints to cool under a heavy weight do not seem to help. I use a Seal release paper sandwich holding the print, mounting tissue, and museum board (as instructed by Seal). I have tested my drymont temperature and it is at the recommended temperature. Have you run into this problem and what was your solution? Thank you.

-- Robert Gertler (gertler.r@ghc.org), March 28, 2002


I've had the same problem. Unfortunately, I don't have a solution. Hopefully, someone else knows.

-- Ted Kaufman (writercrmp@aol.com), March 28, 2002.

Instead of release paper, I use another sheet of museum board on top of the print. This can be reused, although should be changed every so often. You need to be sure that the press is adjusted so that it has the proper pressure on the boards when closed. A quick way to add pressure is to add boards underneath the mounting boards. Or it is possible that you have too much pressure on the boards, and you need to loosen up a bit. I have never had this problem.

-- Michael Feldman (mfeldman@qwest.net), March 28, 2002.

The symptoms are consistent with using too much heat. I would back off the temperature about 5 degrees at a time until the problem goes away. I also agree with the museum board approach. I use two ply and label the sides so I don't accidentally use a side that has faced the platen or the felt against the photograph.

-- Robert A. Zeichner (info@razeichner.com), March 28, 2002.

I had this problem when I first started drymounting. I was able to eliminate it by making sure that the print to be mounted is as flat as possible before mounting. There are several methods to achieve this, but leaving the prints under flat weights for several days will usually do the job. If not, you may need to dampen the backs before putting them under the weights. Using the heat of the press on very slightly dampened prints can also work, but sticking and changing the texture of the front side of the print can occur if you use more that a very slight amount of moisture. I get the worst curling when prints dry rapidly in low humidity conditions, which I counter by putting a small container of water in the drawer I use for print drying. I Hope these suggestions help!

-- David Rose (DERose1@msn.com), March 28, 2002.

All good advice above. However,I think that the main culprite is too high a temperature. Leave the print under a weight, with the matts that you placed over and under it for at least a minute. I use two pieces of 4-ply matt on top and one on the bottom. This means my press time is just over 4 minutes. The extra matts help distribute the temperature more evenly and it cools slower. Different parts of the print cool at different rates. That is why the edges sometimes pull away. Good luck.

-- Paul Mongillo (pmongillo@thurston.com), March 28, 2002.

Do you attach the dry-mount before or after trimming the print?

-- neil poulsen (neil.fg@att.net), March 30, 2002.

Actually I think your problem is not cooling after the mounting, an additional problem to having the platen too hot. After you mount the print and take it out of the press put a few heavy books on top of it, many people think this is to keep th print flat, but actually it serves as a heat transfer sink where the heat goes from the print and board to the book and it sets the glue on the mounting tissue. If you can afford it, get the weight sold at light impressions designed specially for this. I am almost sure of this because my first print exhibited the same problem, after I did what I am telling you I have never had a problem.

-- Jorge Gasteazoro (rossorabbit@hotmail.com), March 30, 2002.

Your press might not be at the temp that the knob is set for. I recently bought a used seal commercial 210m. When I set the knob to 200 degrees, the thermometer read 175. I tested this with a cooking thermometer. (which I've found to be accurate.) Both thermometers read within 5 degrees of each other. I thought I'd put a new thermostat in the dry mount press. When I removed the thermostat, (unplug the thing first.) I noticed on the bottom of the thermostat there was a small hole. Inside was a small screw driver slot. I adjusted this in a very small amount, reinstalling and reheated the press. It took 4 times to get it right. Now when the knob is set to 200 degrees, the thermometer reads from 195 to 205. A couple of important things to note are: The press has to go through a few cycles to get to working temp. If you use extra cover boards ect. then even more cycles are required. If you choose to adjust the thermostat, then you must let the press cool down before attempting to remove the screws holding the thermostat in. This is because they are steel and they screw into aluminum. and they swell and contract at different rates. Its easy to strip the threads in the hole. After an adjustment has been made and the thing has been reassembled, then let the press go through several cycles to arrive at temp. When the thermostat cuts off power the first time, the thermometer continues to rise so don't do anything until it has cycled several times. Like I said, it took me 4 or 5 tries to get it right.

-- dee seegers (deesee@pinn.net), March 30, 2002.

As others have said, the heat on the dry mount press is set too high, regardless of how the thermostat reads.

Cover board: I recommend using Strathmore Bristol Board. It is archival and is perfectly smooth, unlike regular mount board. Even the best board and smoothest board, ArtCare from Superior Archival Materials, is not perfectly smooth.

-- Michael A. Smith (michaelandpaula@michaelandpaula.com), March 31, 2002.

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