Dry hot press dents prints and mat boards...

Discussion in 'Enlarging' started by tkamiya, Mar 10, 2011.

  1. tkamiya

    tkamiya Member

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    When I use my dry hot press, I sandwich prints and backer boards in between two sheets of mat boards for protection and a release paper for non-stick. These boards and release paper are re-used.

    Apparently, when I was drying 8x10 double thickness FB paper, it made an impression on the mat board. When the same mat board was subsequently used to mount a print onto a backer board, it made an impression on the backer board.

    How do I prevent this? Is the platen pressure too high? Is there a process to un-dent (is that a word??) release papers and mat boards used in pressing? It will get expensive if I have to use new boards each time.
     
  2. Brook Hill

    Brook Hill Subscriber

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    I had this problem but seemed to have cured it so far by:-
    a) Squashing the two mount boards as hard I as I could in the heat press for 24 hours at a fairly high temperature..
    b) putting thin card sheets between the print and the thicker mount boards.

    Seems OK at the moment but I am still a little anxious.

    Tony
     
  3. glbeas

    glbeas Member

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    Try a scrap thats been dented and steam the area. If it acts like wood it will swell back to level. Then you can clamp it back in the press and dry it out.
     
  4. nworth

    nworth Subscriber

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    Instead of a release sheet and covering mat board, I've been using a piece of foam on the bottom and a large sheet of aluminum foil on top. The aluminum foil is disposable, in case it gets wrinkled or dirty, but it acts as a good release sheet and conducts heat well. At first I was wary of this scheme, but I've been using it for about 10 years now without any funny attributes transferred to the prints. It is important to keep everything flat, even, and clean.
     
  5. wildbill

    wildbill Member

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    You don't need much pressure since the heat is doing the work. I don't use much pressure at all. Your press should be adjustable.
     
  6. tkamiya

    tkamiya Member

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    Yes, it IS adjustable. How do I guage the appropriate pressure? Is slight deflection on bottom form enough?